Adding upstream version 2.1.30.upstream/2.1.30

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

66 files changed, 12083 insertions, 0 deletions

diff --git a/tools/lint/CMakeLists.txt b/tools/lint/CMakeLists.txt
new file mode 100644
index 0000000..32cdcbf
--- /dev/null
+++ b/tools/lint/CMakeLists.txt
@@ -0,0 +1,90 @@
+# yanglint
+
+if(WIN32)
+    set(YANGLINT_INTERACTIVE OFF)
+else()
+    set(YANGLINT_INTERACTIVE ON)
+endif()
+
+set(lintsrc
+    main_ni.c
+    cmd.c
+    cmd_add.c
+    cmd_clear.c
+    cmd_data.c
+    cmd_list.c
+    cmd_feature.c
+    cmd_load.c
+    cmd_print.c
+    cmd_searchpath.c
+    common.c
+)
+if(YANGLINT_INTERACTIVE)
+    set(lintsrc ${lintsrc}
+        main.c
+        completion.c
+        configuration.c
+        linenoise/linenoise.c)
+else()
+    set(lintsrc ${lintsrc}
+        main_ni_only.c)
+endif()
+
+set(format_sources
+    ${format_sources}
+    ${CMAKE_CURRENT_SOURCE_DIR}/*.c
+    ${CMAKE_CURRENT_SOURCE_DIR}/*.h
+    PARENT_SCOPE)
+
+add_executable(yanglint ${lintsrc} ${compatsrc})
+target_link_libraries(yanglint yang)
+install(TARGETS yanglint DESTINATION ${CMAKE_INSTALL_BINDIR})
+install(FILES ${PROJECT_SOURCE_DIR}/tools/lint/yanglint.1 DESTINATION ${CMAKE_INSTALL_MANDIR}/man1)
+target_include_directories(yanglint BEFORE PRIVATE ${PROJECT_BINARY_DIR})
+
+if(WIN32)
+    target_include_directories(yanglint PRIVATE ${GETOPT_INCLUDE_DIR})
+    target_link_libraries(yanglint ${GETOPT_LIBRARY})
+endif()
+
+#
+# tests
+#
+function(add_yanglint_test)
+    cmake_parse_arguments(ADDTEST "" "NAME;VIA;SCRIPT" "" ${ARGN})
+    set(TEST_NAME yanglint_${ADDTEST_NAME})
+
+    if(${ADDTEST_VIA} STREQUAL "bash")
+        set(WRAPPER /usr/bin/env bash)
+    elseif(${ADDTEST_VIA} STREQUAL "expect")
+        set(WRAPPER ${PATH_EXPECT})
+    else()
+        message(FATAL_ERROR "build: unexpected wrapper '${ADDTEST_VIA}'")
+    endif()
+
+    add_test(NAME ${TEST_NAME} COMMAND ${WRAPPER} ${CMAKE_CURRENT_SOURCE_DIR}/tests/${ADDTEST_SCRIPT})
+    set_property(TEST ${TEST_NAME} APPEND PROPERTY ENVIRONMENT "YANGLINT=${PROJECT_BINARY_DIR}/yanglint")
+    set_property(TEST ${TEST_NAME} APPEND PROPERTY ENVIRONMENT "YANG_MODULES_DIR=${PROJECT_SOURCE_DIR}/tests/modules/yang")
+    set_property(TEST ${TEST_NAME} APPEND PROPERTY ENVIRONMENT "CURRENT_SOURCE_DIR=${CMAKE_CURRENT_SOURCE_DIR}")
+endfunction(add_yanglint_test)
+
+if(ENABLE_TESTS)
+    # tests of non-interactive mode using shunit2
+    find_program(PATH_SHUNIT NAMES shunit2)
+    if(NOT PATH_SHUNIT)
+        message(WARNING "'shunit2' not found! The yanglint(1) non-interactive tests will not be available.")
+    else()
+        add_yanglint_test(NAME ni_list VIA bash SCRIPT shunit2/list.sh)
+        add_yanglint_test(NAME ni_feature VIA bash SCRIPT shunit2/feature.sh)
+    endif()
+
+    # tests of interactive mode using expect
+    find_program(PATH_EXPECT NAMES expect)
+    if(NOT PATH_EXPECT)
+        message(WARNING "'expect' not found! The yanglint(1) interactive tests will not be available.")
+    elseif(YANGLINT_INTERACTIVE)
+        add_yanglint_test(NAME in_list VIA expect SCRIPT expect/list.exp)
+        add_yanglint_test(NAME in_feature VIA expect SCRIPT expect/feature.exp)
+        add_yanglint_test(NAME in_completion VIA expect SCRIPT expect/completion.exp)
+    endif()
+endif()
diff --git a/tools/lint/cmd.c b/tools/lint/cmd.c
new file mode 100644
index 0000000..10e7446
--- /dev/null
+++ b/tools/lint/cmd.c
@@ -0,0 +1,259 @@
+/**
+ * @file cmd.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief libyang's yanglint tool general commands
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <getopt.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <strings.h>
+
+#include "common.h"
+#include "compat.h"
+#include "libyang.h"
+
+COMMAND commands[];
+extern int done;
+
+#ifndef NDEBUG
+
+void
+cmd_debug_help(void)
+{
+    printf("Usage: debug (dict | xpath)+\n");
+}
+
+void
+cmd_debug(struct ly_ctx **UNUSED(ctx), const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"help", no_argument, NULL, 'h'},
+        {NULL, 0, NULL, 0}
+    };
+    uint32_t dbg_groups = 0;
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "h", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'h':
+            cmd_debug_help();
+            goto cleanup;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+    if (argc == optind) {
+        /* no argument */
+        cmd_debug_help();
+        goto cleanup;
+    }
+
+    for (int i = 0; i < argc - optind; i++) {
+        if (!strcasecmp("dict", argv[optind + i])) {
+            dbg_groups |= LY_LDGDICT;
+        } else if (!strcasecmp("xpath", argv[optind + i])) {
+            dbg_groups |= LY_LDGXPATH;
+        } else {
+            YLMSG_E("Unknown debug group \"%s\"\n", argv[optind + 1]);
+            goto cleanup;
+        }
+    }
+
+    ly_log_dbg_groups(dbg_groups);
+
+cleanup:
+    free_cmdline(argv);
+}
+
+#endif
+
+void
+cmd_verb_help(void)
+{
+    printf("Usage: verb (error | warning | verbose | debug)\n");
+}
+
+void
+cmd_verb(struct ly_ctx **UNUSED(ctx), const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"help", no_argument, NULL, 'h'},
+        {NULL, 0, NULL, 0}
+    };
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "h", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'h':
+            cmd_verb_help();
+            goto cleanup;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (argc - optind > 1) {
+        YLMSG_E("Only a single verbosity level can be set.\n");
+        cmd_verb_help();
+        goto cleanup;
+    } else if (argc == optind) {
+        /* no argument - print current value */
+        LY_LOG_LEVEL level = ly_log_level(LY_LLERR);
+
+        ly_log_level(level);
+        printf("Current verbosity level: ");
+        if (level == LY_LLERR) {
+            printf("error\n");
+        } else if (level == LY_LLWRN) {
+            printf("warning\n");
+        } else if (level == LY_LLVRB) {
+            printf("verbose\n");
+        } else if (level == LY_LLDBG) {
+            printf("debug\n");
+        }
+        goto cleanup;
+    }
+
+    if (!strcasecmp("error", argv[optind]) || !strcmp("0", argv[optind])) {
+        ly_log_level(LY_LLERR);
+    } else if (!strcasecmp("warning", argv[optind]) || !strcmp("1", argv[optind])) {
+        ly_log_level(LY_LLWRN);
+    } else if (!strcasecmp("verbose", argv[optind]) || !strcmp("2", argv[optind])) {
+        ly_log_level(LY_LLVRB);
+    } else if (!strcasecmp("debug", argv[optind]) || !strcmp("3", argv[optind])) {
+        ly_log_level(LY_LLDBG);
+    } else {
+        YLMSG_E("Unknown verbosity \"%s\"\n", argv[optind]);
+        goto cleanup;
+    }
+
+cleanup:
+    free_cmdline(argv);
+}
+
+void
+cmd_quit(struct ly_ctx **UNUSED(ctx), const char *UNUSED(cmdline))
+{
+    done = 1;
+    return;
+}
+
+void
+cmd_help_help(void)
+{
+    printf("Usage: help [cmd ...]\n");
+}
+
+void
+cmd_help(struct ly_ctx **UNUSED(ctx), const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"help", no_argument, NULL, 'h'},
+        {NULL, 0, NULL, 0}
+    };
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "h", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'h':
+            cmd_help_help();
+            goto cleanup;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (argc == optind) {
+generic_help:
+        printf("Available commands:\n");
+        for (uint16_t i = 0; commands[i].name; i++) {
+            if (commands[i].helpstring != NULL) {
+                printf("  %-15s %s\n", commands[i].name, commands[i].helpstring);
+            }
+        }
+    } else {
+        /* print specific help for the selected command(s) */
+
+        for (int c = 0; c < argc - optind; ++c) {
+            int8_t match = 0;
+
+            /* get the command of the specified name */
+            for (uint16_t i = 0; commands[i].name; i++) {
+                if (strcmp(argv[optind + c], commands[i].name) == 0) {
+                    match = 1;
+                    if (commands[i].help_func != NULL) {
+                        commands[i].help_func();
+                    } else {
+                        printf("%s: %s\n", argv[optind + c], commands[i].helpstring);
+                    }
+                    break;
+                }
+            }
+            if (!match) {
+                /* if unknown command specified, print the list of commands */
+                printf("Unknown command \'%s\'\n", argv[optind + c]);
+                goto generic_help;
+            }
+        }
+    }
+
+cleanup:
+    free_cmdline(argv);
+}
+
+COMMAND commands[] = {
+    {"help", cmd_help, cmd_help_help, "Display commands description"},
+    {"add", cmd_add, cmd_add_help, "Add a new module from a specific file"},
+    {"load", cmd_load, cmd_load_help, "Load a new schema from the searchdirs"},
+    {"print", cmd_print, cmd_print_help, "Print a module"},
+    {"data", cmd_data, cmd_data_help, "Load, validate and optionally print instance data"},
+    {"list", cmd_list, cmd_list_help, "List all the loaded modules"},
+    {"feature", cmd_feature, cmd_feature_help, "Print all features of module(s) with their state"},
+    {"searchpath", cmd_searchpath, cmd_searchpath_help, "Print/set the search path(s) for schemas"},
+    {"clear", cmd_clear, cmd_clear_help, "Clear the context - remove all the loaded modules"},
+    {"verb", cmd_verb, cmd_verb_help, "Change verbosity"},
+#ifndef NDEBUG
+    {"debug", cmd_debug, cmd_debug_help, "Display specific debug message groups"},
+#endif
+    {"quit", cmd_quit, NULL, "Quit the program"},
+    /* synonyms for previous commands */
+    {"?", cmd_help, NULL, "Display commands description"},
+    {"exit", cmd_quit, NULL, "Quit the program"},
+    {NULL, NULL, NULL, NULL}
+};
diff --git a/tools/lint/cmd.h b/tools/lint/cmd.h
new file mode 100644
index 0000000..9f6f88d
--- /dev/null
+++ b/tools/lint/cmd.h
@@ -0,0 +1,69 @@
+/**
+ * @file cmd.h
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief libyang's yanglint tool commands header
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#ifndef COMMANDS_H_
+#define COMMANDS_H_
+
+#include "libyang.h"
+
+/**
+ * @brief command information
+ */
+typedef struct {
+    char *name;                                      /* User printable name of the function. */
+
+    void (*func)(struct ly_ctx **ctx, const char *); /* Function to call to do the command. */
+    void (*help_func)(void);                         /* Display command help. */
+    char *helpstring;                                /* Documentation for this function. */
+} COMMAND;
+
+/**
+ * @brief The list of available commands.
+ */
+extern COMMAND commands[];
+
+/* cmd_add.c */
+void cmd_add(struct ly_ctx **ctx, const char *cmdline);
+void cmd_add_help(void);
+
+/* cmd_clear.c */
+void cmd_clear(struct ly_ctx **ctx, const char *cmdline);
+void cmd_clear_help(void);
+
+/* cmd_data.c */
+void cmd_data(struct ly_ctx **ctx, const char *cmdline);
+void cmd_data_help(void);
+
+/* cmd_list.c */
+void cmd_list(struct ly_ctx **ctx, const char *cmdline);
+void cmd_list_help(void);
+
+/* cmd_feature.c */
+void cmd_feature(struct ly_ctx **ctx, const char *cmdline);
+void cmd_feature_help(void);
+
+/* cmd_load.c */
+void cmd_load(struct ly_ctx **ctx, const char *cmdline);
+void cmd_load_help(void);
+
+/* cmd_print.c */
+void cmd_print(struct ly_ctx **ctx, const char *cmdline);
+void cmd_print_help(void);
+
+/* cmd_searchpath.c */
+void cmd_searchpath(struct ly_ctx **ctx, const char *cmdline);
+void cmd_searchpath_help(void);
+
+#endif /* COMMANDS_H_ */
diff --git a/tools/lint/cmd_add.c b/tools/lint/cmd_add.c
new file mode 100644
index 0000000..bbfdfd6
--- /dev/null
+++ b/tools/lint/cmd_add.c
@@ -0,0 +1,176 @@
+/**
+ * @file cmd_add.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief 'add' command of the libyang's yanglint tool.
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <getopt.h>
+#include <libgen.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "libyang.h"
+
+#include "common.h"
+
+void
+cmd_add_help(void)
+{
+    printf("Usage: add [-iD] <schema1> [<schema2> ...]\n"
+            "                  Add a new module from a specific file.\n\n"
+            "  -D, --disable-searchdir\n"
+            "                  Do not implicitly search in current working directory for\n"
+            "                  the import schema modules. If specified a second time, do not\n"
+            "                  even search in the module directory (all modules must be \n"
+            "                  explicitly specified).\n"
+            "  -F FEATURES, --features=FEATURES\n"
+            "                  Features to support, default all in all implemented modules.\n"
+            "                  Specify separately for each module.\n"
+            "                  <modname>:[<feature>,]*\n"
+            "  -i, --make-implemented\n"
+            "                  Make the imported modules \"referenced\" from any loaded\n"
+            "                  <schema> module also implemented. If specified a second time,\n"
+            "                  all the modules are set implemented.\n");
+}
+
+void
+cmd_add(struct ly_ctx **ctx, const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"disable-searchdir", no_argument, NULL, 'D'},
+        {"features", required_argument, NULL, 'F'},
+        {"help", no_argument, NULL, 'h'},
+        {"make-implemented", no_argument, NULL, 'i'},
+        {NULL, 0, NULL, 0}
+    };
+    uint16_t options_ctx = 0;
+    const char *all_features[] = {"*", NULL};
+    struct ly_set fset = {0};
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "D:F:hi", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'D': /* --disable--search */
+            if (options_ctx & LY_CTX_DISABLE_SEARCHDIRS) {
+                YLMSG_W("The -D option specified too many times.\n");
+            }
+            if (options_ctx & LY_CTX_DISABLE_SEARCHDIR_CWD) {
+                options_ctx &= ~LY_CTX_DISABLE_SEARCHDIR_CWD;
+                options_ctx |= LY_CTX_DISABLE_SEARCHDIRS;
+            } else {
+                options_ctx |= LY_CTX_DISABLE_SEARCHDIR_CWD;
+            }
+            break;
+
+        case 'F': /* --features */
+            if (parse_features(optarg, &fset)) {
+                goto cleanup;
+            }
+            break;
+
+        case 'h':
+            cmd_add_help();
+            goto cleanup;
+
+        case 'i': /* --make-implemented */
+            if (options_ctx & LY_CTX_REF_IMPLEMENTED) {
+                options_ctx &= ~LY_CTX_REF_IMPLEMENTED;
+                options_ctx |= LY_CTX_ALL_IMPLEMENTED;
+            } else {
+                options_ctx |= LY_CTX_REF_IMPLEMENTED;
+            }
+            break;
+
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (argc == optind) {
+        /* no argument */
+        cmd_add_help();
+        goto cleanup;
+    }
+
+    if (!fset.count) {
+        /* no features, enable all of them */
+        options_ctx |= LY_CTX_ENABLE_IMP_FEATURES;
+    }
+
+    if (options_ctx) {
+        ly_ctx_set_options(*ctx, options_ctx);
+    }
+
+    for (int i = 0; i < argc - optind; i++) {
+        /* process the schema module files */
+        LY_ERR ret;
+        uint8_t path_unset = 1; /* flag to unset the path from the searchpaths list (if not already present) */
+        char *dir, *module;
+        const char **features = NULL;
+        struct ly_in *in = NULL;
+
+        if (parse_schema_path(argv[optind + i], &dir, &module)) {
+            goto cleanup;
+        }
+
+        /* add temporarily also the path of the module itself */
+        if (ly_ctx_set_searchdir(*ctx, dirname(dir)) == LY_EEXIST) {
+            path_unset = 0;
+        }
+
+        /* get features list for this module */
+        if (!fset.count) {
+            features = all_features;
+        } else {
+            get_features(&fset, module, &features);
+        }
+
+        /* temporary cleanup */
+        free(dir);
+        free(module);
+
+        /* prepare input handler */
+        ret = ly_in_new_filepath(argv[optind + i], 0, &in);
+        if (ret) {
+            goto cleanup;
+        }
+
+        /* parse the file */
+        ret = lys_parse(*ctx, in, LYS_IN_UNKNOWN, features, NULL);
+        ly_in_free(in, 1);
+        ly_ctx_unset_searchdir_last(*ctx, path_unset);
+
+        if (ret) {
+            /* libyang printed the error messages */
+            goto cleanup;
+        }
+    }
+
+cleanup:
+    if (options_ctx) {
+        ly_ctx_unset_options(*ctx, options_ctx);
+    }
+    ly_set_erase(&fset, free_features);
+    free_cmdline(argv);
+}
diff --git a/tools/lint/cmd_clear.c b/tools/lint/cmd_clear.c
new file mode 100644
index 0000000..5eed6ff
--- /dev/null
+++ b/tools/lint/cmd_clear.c
@@ -0,0 +1,99 @@
+/**
+ * @file cmd_clear.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief 'clear' command of the libyang's yanglint tool.
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <getopt.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include "libyang.h"
+
+#include "common.h"
+
+void
+cmd_clear_help(void)
+{
+    printf("Usage: clear [-i] [-y]\n"
+            "                  Replace the current context with an empty one, searchpaths\n"
+            "                  are not kept.\n\n"
+            "  -i, --make-implemented\n"
+            "                Make the imported modules \"referenced\" from any loaded\n"
+            "                module also implemented. If specified a second time, all the\n"
+            "                modules are set implemented.\n"
+            "  -y, --yang-library\n"
+            "                  Load and implement internal \"ietf-yang-library\" YANG module.\n"
+            "                  Note that this module includes definitions of mandatory state\n"
+            "                  data that can result in unexpected data validation errors.\n");
+#if 0
+    "                  If <yang-library-data> path specified, load the modules\n"
+    "                  according to the provided yang library data.\n"
+#endif
+}
+
+void
+cmd_clear(struct ly_ctx **ctx, const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"make-implemented", no_argument, NULL, 'i'},
+        {"yang-library",     no_argument, NULL, 'y'},
+        {"help",             no_argument, NULL, 'h'},
+        {NULL, 0, NULL, 0}
+    };
+    uint16_t options_ctx = LY_CTX_NO_YANGLIBRARY;
+    struct ly_ctx *ctx_new;
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "iyh", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'i':
+            if (options_ctx & LY_CTX_REF_IMPLEMENTED) {
+                options_ctx &= ~LY_CTX_REF_IMPLEMENTED;
+                options_ctx |= LY_CTX_ALL_IMPLEMENTED;
+            } else {
+                options_ctx |= LY_CTX_REF_IMPLEMENTED;
+            }
+            break;
+        case 'y':
+            options_ctx &= ~LY_CTX_NO_YANGLIBRARY;
+            break;
+        case 'h':
+            cmd_clear_help();
+            goto cleanup;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (ly_ctx_new(NULL, options_ctx, &ctx_new)) {
+        YLMSG_W("Failed to create context.\n");
+        goto cleanup;
+    }
+
+    ly_ctx_destroy(*ctx);
+    *ctx = ctx_new;
+
+cleanup:
+    free_cmdline(argv);
+}
diff --git a/tools/lint/cmd_data.c b/tools/lint/cmd_data.c
new file mode 100644
index 0000000..25449f5
--- /dev/null
+++ b/tools/lint/cmd_data.c
@@ -0,0 +1,328 @@
+/**
+ * @file cmd_data.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief 'data' command of the libyang's yanglint tool.
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <errno.h>
+#include <getopt.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <strings.h>
+
+#include "libyang.h"
+
+#include "common.h"
+
+void
+cmd_data_help(void)
+{
+    printf("Usage: data [-emn] [-t TYPE]\n"
+            "            [-F FORMAT] [-f FORMAT] [-d DEFAULTS] [-o OUTFILE] <data1> ...\n"
+            "       data [-n] -t (rpc | notif | reply) [-O FILE]\n"
+            "            [-F FORMAT] [-f FORMAT] [-d DEFAULTS] [-o OUTFILE] <data1> ...\n"
+            "       data [-en] [-t TYPE] [-F FORMAT] -x XPATH [-o OUTFILE] <data1> ...\n"
+            "                  Parse, validate and optionally print data instances\n\n"
+
+            "  -t TYPE, --type=TYPE\n"
+            "                Specify data tree type in the input data file(s):\n"
+            "        data          - Complete datastore with status data (default type).\n"
+            "        config        - Configuration datastore (without status data).\n"
+            "        get           - Result of the NETCONF <get> operation.\n"
+            "        getconfig     - Result of the NETCONF <get-config> operation.\n"
+            "        edit          - Content of the NETCONF <edit-config> operation.\n"
+            "        rpc           - Content of the NETCONF <rpc> message, defined as YANG's\n"
+            "                        RPC/Action input statement.\n"
+            "        reply         - Reply to the RPC/Action. Note that the reply data are\n"
+            "                        expected inside a container representing the original\n"
+            "                        RPC/Action. This is necessary to identify appropriate\n"
+            "                        data definitions in the schema module.\n"
+            "        notif         - Notification instance (content of the <notification>\n"
+            "                        element without <eventTime>).\n\n"
+
+            "  -e, --present Validate only with the schema modules whose data actually\n"
+            "                exist in the provided input data files. Takes effect only\n"
+            "                with the 'data' or 'config' TYPEs. Used to avoid requiring\n"
+            "                mandatory nodes from modules which data are not present in the\n"
+            "                provided input data files.\n"
+            "  -m, --merge   Merge input data files into a single tree and validate at\n"
+            "                once.The option has effect only for 'data' and 'config' TYPEs.\n"
+            "                In case of using -x option, the data are always merged.\n"
+            "  -n, --not-strict\n"
+            "                Do not require strict data parsing (silently skip unknown data),\n"
+            "                has no effect for schemas.\n\n"
+            "  -O FILE, --operational=FILE\n"
+            "                Provide optional data to extend validation of the 'rpc',\n"
+            "                'reply' or 'notif' TYPEs. The FILE is supposed to contain\n"
+            "                the :running configuration datastore and state data\n"
+            "                (operational datastore) referenced from the RPC/Notification.\n\n"
+
+            "  -f FORMAT, --format=FORMAT\n"
+            "                Print the data in one of the following formats:\n"
+            "                xml, json, lyb\n"
+            "                Note that the LYB format requires the -o option specified.\n"
+            "  -F FORMAT, --in-format=FORMAT\n"
+            "                Load the data in one of the following formats:\n"
+            "                xml, json, lyb\n"
+            "                If input format not specified, it is detected from the file extension.\n"
+            "  -d MODE, --default=MODE\n"
+            "                Print data with default values, according to the MODE\n"
+            "                (to print attributes, ietf-netconf-with-defaults model\n"
+            "                must be loaded):\n"
+            "      all             - Add missing default nodes.\n"
+            "      all-tagged      - Add missing default nodes and mark all the default\n"
+            "                        nodes with the attribute.\n"
+            "      trim            - Remove all nodes with a default value.\n"
+            "      implicit-tagged - Add missing nodes and mark them with the attribute.\n"
+            "  -o OUTFILE, --output=OUTFILE\n"
+            "                Write the output to OUTFILE instead of stdout.\n\n"
+
+            "  -x XPATH, --xpath=XPATH\n"
+            "                Evaluate XPATH expression and print the nodes satysfying the.\n"
+            "                expression. The output format is specific and the option cannot\n"
+            "                be combined with the -f and -d options. Also all the data\n"
+            "                inputs are merged into a single data tree where the expression\n"
+            "                is evaluated, so the -m option is always set implicitly.\n\n");
+
+}
+
+void
+cmd_data(struct ly_ctx **ctx, const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"defaults",    required_argument, NULL, 'd'},
+        {"present",     no_argument,       NULL, 'e'},
+        {"format",      required_argument, NULL, 'f'},
+        {"in-format",   required_argument, NULL, 'F'},
+        {"help",        no_argument,       NULL, 'h'},
+        {"merge",       no_argument,       NULL, 'm'},
+        {"output",      required_argument, NULL, 'o'},
+        {"operational", required_argument, NULL, 'O'},
+        {"not-strict",  no_argument,       NULL, 'n'},
+        {"type",        required_argument, NULL, 't'},
+        {"xpath",       required_argument, NULL, 'x'},
+        {NULL, 0, NULL, 0}
+    };
+
+    uint8_t data_merge = 0;
+    uint32_t options_print = 0;
+    uint32_t options_parse = YL_DEFAULT_DATA_PARSE_OPTIONS;
+    uint32_t options_validate = 0;
+    enum lyd_type data_type = 0;
+    uint8_t data_type_set = 0;
+    LYD_FORMAT outformat = LYD_UNKNOWN;
+    LYD_FORMAT informat = LYD_UNKNOWN;
+    struct ly_out *out = NULL;
+    struct cmdline_file *operational = NULL;
+    struct ly_set inputs = {0};
+    struct ly_set xpaths = {0};
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "d:ef:F:hmo:O:r:nt:x:", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'd': /* --default */
+            if (!strcasecmp(optarg, "all")) {
+                options_print = (options_print & ~LYD_PRINT_WD_MASK) | LYD_PRINT_WD_ALL;
+            } else if (!strcasecmp(optarg, "all-tagged")) {
+                options_print = (options_print & ~LYD_PRINT_WD_MASK) | LYD_PRINT_WD_ALL_TAG;
+            } else if (!strcasecmp(optarg, "trim")) {
+                options_print = (options_print & ~LYD_PRINT_WD_MASK) | LYD_PRINT_WD_TRIM;
+            } else if (!strcasecmp(optarg, "implicit-tagged")) {
+                options_print = (options_print & ~LYD_PRINT_WD_MASK) | LYD_PRINT_WD_IMPL_TAG;
+            } else {
+                YLMSG_E("Unknown default mode %s\n", optarg);
+                cmd_data_help();
+                goto cleanup;
+            }
+            break;
+        case 'f': /* --format */
+            if (!strcasecmp(optarg, "xml")) {
+                outformat = LYD_XML;
+            } else if (!strcasecmp(optarg, "json")) {
+                outformat = LYD_JSON;
+            } else if (!strcasecmp(optarg, "lyb")) {
+                outformat = LYD_LYB;
+            } else {
+                YLMSG_E("Unknown output format %s\n", optarg);
+                cmd_data_help();
+                goto cleanup;
+            }
+            break;
+        case 'F': /* --in-format */
+            if (!strcasecmp(optarg, "xml")) {
+                informat = LYD_XML;
+            } else if (!strcasecmp(optarg, "json")) {
+                informat = LYD_JSON;
+            } else if (!strcasecmp(optarg, "lyb")) {
+                informat = LYD_LYB;
+            } else {
+                YLMSG_E("Unknown input format %s\n", optarg);
+                cmd_data_help();
+                goto cleanup;
+            }
+            break;
+        case 'o': /* --output */
+            if (out) {
+                YLMSG_E("Only a single output can be specified.\n");
+                goto cleanup;
+            } else {
+                if (ly_out_new_filepath(optarg, &out)) {
+                    YLMSG_E("Unable open output file %s (%s)\n", optarg, strerror(errno));
+                    goto cleanup;
+                }
+            }
+            break;
+        case 'O': { /* --operational */
+            struct ly_in *in;
+            LYD_FORMAT f;
+
+            if (operational) {
+                YLMSG_E("The operational datastore (-O) cannot be set multiple times.\n");
+                goto cleanup;
+            }
+            if (get_input(optarg, NULL, &f, &in)) {
+                goto cleanup;
+            }
+            operational = fill_cmdline_file(NULL, in, optarg, f);
+            break;
+        } /* case 'O' */
+
+        case 'e': /* --present */
+            options_validate |= LYD_VALIDATE_PRESENT;
+            break;
+        case 'm': /* --merge */
+            data_merge = 1;
+            break;
+        case 'n': /* --not-strict */
+            options_parse &= ~LYD_PARSE_STRICT;
+            break;
+        case 't': /* --type */
+            if (data_type_set) {
+                YLMSG_E("The data type (-t) cannot be set multiple times.\n");
+                goto cleanup;
+            }
+
+            if (!strcasecmp(optarg, "config")) {
+                options_parse |= LYD_PARSE_NO_STATE;
+                options_validate |= LYD_VALIDATE_NO_STATE;
+            } else if (!strcasecmp(optarg, "get")) {
+                options_parse |= LYD_PARSE_ONLY;
+            } else if (!strcasecmp(optarg, "getconfig") || !strcasecmp(optarg, "get-config") || !strcasecmp(optarg, "edit")) {
+                options_parse |= LYD_PARSE_ONLY | LYD_PARSE_NO_STATE;
+            } else if (!strcasecmp(optarg, "rpc") || !strcasecmp(optarg, "action")) {
+                data_type = LYD_TYPE_RPC_YANG;
+            } else if (!strcasecmp(optarg, "reply") || !strcasecmp(optarg, "rpcreply")) {
+                data_type = LYD_TYPE_REPLY_YANG;
+            } else if (!strcasecmp(optarg, "notif") || !strcasecmp(optarg, "notification")) {
+                data_type = LYD_TYPE_NOTIF_YANG;
+            } else if (!strcasecmp(optarg, "data")) {
+                /* default option */
+            } else {
+                YLMSG_E("Unknown data tree type %s.\n", optarg);
+                cmd_data_help();
+                goto cleanup;
+            }
+
+            data_type_set = 1;
+            break;
+
+        case 'x': /* --xpath */
+            if (ly_set_add(&xpaths, optarg, 0, NULL)) {
+                YLMSG_E("Storing XPath \"%s\" failed.\n", optarg);
+                goto cleanup;
+            }
+            break;
+
+        case 'h': /* --help */
+            cmd_data_help();
+            goto cleanup;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (optind == argc) {
+        YLMSG_E("Missing the data file to process.\n");
+        goto cleanup;
+    }
+
+    if (data_merge) {
+        if (data_type || (options_parse & LYD_PARSE_ONLY)) {
+            /* switch off the option, incompatible input data type */
+            data_merge = 0;
+        } else {
+            /* postpone validation after the merge of all the input data */
+            options_parse |= LYD_PARSE_ONLY;
+        }
+    } else if (xpaths.count) {
+        data_merge = 1;
+    }
+
+    if (xpaths.count && outformat) {
+        YLMSG_E("The --format option cannot be combined with --xpath option.\n");
+        cmd_data_help();
+        goto cleanup;
+    }
+
+    if (operational && !data_type) {
+        YLMSG_W("Operational datastore takes effect only with RPCs/Actions/Replies/Notifications input data types.\n");
+        free_cmdline_file(operational);
+        operational = NULL;
+    }
+
+    /* process input data files provided as standalone command line arguments */
+    for (int i = 0; i < argc - optind; i++) {
+        struct ly_in *in;
+
+        if (get_input(argv[optind + i], NULL, &informat, &in)) {
+            goto cleanup;
+        }
+
+        if (!fill_cmdline_file(&inputs, in, argv[optind + i], informat)) {
+            ly_in_free(in, 1);
+            goto cleanup;
+        }
+    }
+
+    /* default output stream */
+    if (!out) {
+        if (ly_out_new_file(stdout, &out)) {
+            YLMSG_E("Unable to set stdout as output.\n");
+            goto cleanup;
+        }
+    }
+
+    /* parse, validate and print data */
+    if (process_data(*ctx, data_type, data_merge, outformat, out, options_parse, options_validate, options_print,
+            operational, NULL, &inputs, &xpaths)) {
+        goto cleanup;
+    }
+
+cleanup:
+    ly_out_free(out, NULL, 0);
+    ly_set_erase(&inputs, free_cmdline_file);
+    ly_set_erase(&xpaths, NULL);
+    free_cmdline_file(operational);
+    free_cmdline(argv);
+}
diff --git a/tools/lint/cmd_feature.c b/tools/lint/cmd_feature.c
new file mode 100644
index 0000000..6b332ab
--- /dev/null
+++ b/tools/lint/cmd_feature.c
@@ -0,0 +1,135 @@
+/**
+ * @file cmd_feature.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @brief 'feature' command of the libyang's yanglint tool.
+ *
+ * Copyright (c) 2015-2021 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <getopt.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include "libyang.h"
+
+#include "common.h"
+
+void
+cmd_feature_help(void)
+{
+    printf("Usage: feature [-f] <module> [<module>]*\n"
+            "       feature -a [-f]\n"
+            "                  Print features of all the modules with state of each one.\n\n"
+            "  -f <module1, module2, ...>, --feature-param <module1, module2, ...>\n"
+            "                  Generate features parameter for the command \"add\" \n"
+            "                  in the form of -F <module-name>:<features>\n"
+            "  -a, --all \n"
+            "                  Print features of all implemented modules.\n");
+}
+
+void
+cmd_feature(struct ly_ctx **ctx, const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    char *features_output = NULL;
+    int opt, opt_index, i;
+    ly_bool generate_features = 0, print_all = 0;
+    struct ly_set set = {0};
+    const struct lys_module *mod;
+    struct ly_out *out = NULL;
+    struct option options[] = {
+        {"help", no_argument, NULL, 'h'},
+        {"all", no_argument, NULL, 'a'},
+        {"feature-param", no_argument, NULL, 'f'},
+        {NULL, 0, NULL, 0}
+    };
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "haf", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'h':
+            cmd_feature_help();
+            goto cleanup;
+        case 'a':
+            print_all = 1;
+            break;
+        case 'f':
+            generate_features = 1;
+            break;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (ly_out_new_file(stdout, &out)) {
+        YLMSG_E("Unable to print to the standard output.\n");
+        goto cleanup;
+    }
+
+    if (print_all) {
+        if (print_all_features(out, *ctx, generate_features, &features_output)) {
+            YLMSG_E("Printing all features failed.\n");
+            goto cleanup;
+        }
+        if (generate_features) {
+            printf("%s\n", features_output);
+        }
+        goto cleanup;
+    }
+
+    if (argc == optind) {
+        YLMSG_E("Missing modules to print.\n");
+        goto cleanup;
+    }
+
+    for (i = 0; i < argc - optind; i++) {
+        /* always erase the set, so the previous module's features don't carry over to the next module's features */
+        ly_set_erase(&set, NULL);
+
+        mod = ly_ctx_get_module_latest(*ctx, argv[optind + i]);
+        if (!mod) {
+            YLMSG_E("Module \"%s\" not found.\n", argv[optind + i]);
+            goto cleanup;
+        }
+
+        /* collect features of the module */
+        if (collect_features(mod, &set)) {
+            goto cleanup;
+        }
+
+        if (generate_features) {
+            if (generate_features_output(mod, &set, &features_output)) {
+                goto cleanup;
+            }
+            /* don't print features and their state of each module if generating features parameter */
+            continue;
+        }
+
+        print_features(out, mod, &set);
+    }
+
+    if (generate_features) {
+        printf("%s\n", features_output);
+    }
+
+cleanup:
+    free_cmdline(argv);
+    ly_out_free(out, NULL, 0);
+    ly_set_erase(&set, NULL);
+    free(features_output);
+}
diff --git a/tools/lint/cmd_list.c b/tools/lint/cmd_list.c
new file mode 100644
index 0000000..ec7a021
--- /dev/null
+++ b/tools/lint/cmd_list.c
@@ -0,0 +1,89 @@
+/**
+ * @file cmd_list.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief 'list' command of the libyang's yanglint tool.
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <getopt.h>
+#include <stdio.h>
+#include <strings.h>
+
+#include "libyang.h"
+
+#include "common.h"
+
+void
+cmd_list_help(void)
+{
+    printf("Usage: list [-f (xml | json)]\n"
+            "                  Print the list of modules in the current context\n\n"
+            "  -f FORMAT, --format=FORMAT\n"
+            "                  Print the list as ietf-yang-library data in the specified\n"
+            "                  data FORMAT. If format not specified, a simple list is\n"
+            "                  printed with an indication of imported (i) / implemented (I)\n"
+            "                  modules.\n");
+}
+
+void
+cmd_list(struct ly_ctx **ctx, const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"format", required_argument, NULL, 'f'},
+        {"help", no_argument, NULL, 'h'},
+        {NULL, 0, NULL, 0}
+    };
+    LYD_FORMAT format = LYD_UNKNOWN;
+    struct ly_out *out = NULL;
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "f:h", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'f': /* --format */
+            if (!strcasecmp(optarg, "xml")) {
+                format = LYD_XML;
+            } else if (!strcasecmp(optarg, "json")) {
+                format = LYD_JSON;
+            } else {
+                YLMSG_E("Unknown output format %s\n", optarg);
+                cmd_list_help();
+                goto cleanup;
+            }
+            break;
+        case 'h':
+            cmd_list_help();
+            goto cleanup;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (!ly_out_new_file(stdout, &out)) {
+        print_list(out, *ctx, format);
+        ly_out_free(out, NULL,  0);
+    } else {
+        YLMSG_E("Unable to print to the standard output.\n");
+    }
+
+cleanup:
+    free_cmdline(argv);
+}
diff --git a/tools/lint/cmd_load.c b/tools/lint/cmd_load.c
new file mode 100644
index 0000000..f5883e9
--- /dev/null
+++ b/tools/lint/cmd_load.c
@@ -0,0 +1,139 @@
+/**
+ * @file cmd_load.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief 'load' command of the libyang's yanglint tool.
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <getopt.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "libyang.h"
+
+#include "common.h"
+
+void
+cmd_load_help(void)
+{
+    printf("Usage: load [-i] <module-name1>[@<revision>] [<module-name2>[@revision] ...]\n"
+            "                  Add a new module of the specified name, yanglint will find\n"
+            "                  them in searchpaths. if the <revision> of the module not\n"
+            "                  specified, the latest revision available is loaded.\n\n"
+            "  -F FEATURES, --features=FEATURES\n"
+            "                  Features to support, default all in all implemented modules.\n"
+            "                  <modname>:[<feature>,]*\n"
+            "  -i, --make-implemented\n"
+            "                  Make the imported modules \"referenced\" from any loaded\n"
+            "                  <schema> module also implemented. If specified a second time,\n"
+            "                  all the modules are set implemented.\n");
+}
+
+void
+cmd_load(struct ly_ctx **ctx, const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"features", required_argument, NULL, 'F'},
+        {"help", no_argument, NULL, 'h'},
+        {"make-implemented", no_argument, NULL, 'i'},
+        {NULL, 0, NULL, 0}
+    };
+    uint16_t options_ctx = 0;
+    const char *all_features[] = {"*", NULL};
+    struct ly_set fset = {0};
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "F:hi", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'F': /* --features */
+            if (parse_features(optarg, &fset)) {
+                goto cleanup;
+            }
+            break;
+
+        case 'h':
+            cmd_load_help();
+            goto cleanup;
+
+        case 'i': /* --make-implemented */
+            if (options_ctx & LY_CTX_REF_IMPLEMENTED) {
+                options_ctx &= ~LY_CTX_REF_IMPLEMENTED;
+                options_ctx |= LY_CTX_ALL_IMPLEMENTED;
+            } else {
+                options_ctx |= LY_CTX_REF_IMPLEMENTED;
+            }
+            break;
+
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (argc == optind) {
+        /* no argument */
+        cmd_add_help();
+        goto cleanup;
+    }
+
+    if (!fset.count) {
+        /* no features, enable all of them */
+        options_ctx |= LY_CTX_ENABLE_IMP_FEATURES;
+    }
+
+    if (options_ctx) {
+        ly_ctx_set_options(*ctx, options_ctx);
+    }
+
+    for (int i = 0; i < argc - optind; i++) {
+        /* process the schema module files */
+        char *revision;
+        const char **features = NULL;
+
+        /* get revision */
+        revision = strchr(argv[optind + i], '@');
+        if (revision) {
+            revision[0] = '\0';
+            ++revision;
+        }
+
+        /* get features list for this module */
+        if (!fset.count) {
+            features = all_features;
+        } else {
+            get_features(&fset, argv[optind + i], &features);
+        }
+
+        /* load the module */
+        if (!ly_ctx_load_module(*ctx, argv[optind + i], revision, features)) {
+            /* libyang printed the error messages */
+            goto cleanup;
+        }
+    }
+
+cleanup:
+    if (options_ctx) {
+        ly_ctx_unset_options(*ctx, options_ctx);
+    }
+    ly_set_erase(&fset, free_features);
+    free_cmdline(argv);
+}
diff --git a/tools/lint/cmd_print.c b/tools/lint/cmd_print.c
new file mode 100644
index 0000000..c1a5359
--- /dev/null
+++ b/tools/lint/cmd_print.c
@@ -0,0 +1,264 @@
+/**
+ * @file cmd_print.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief 'print' command of the libyang's yanglint tool.
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <errno.h>
+#include <getopt.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <strings.h>
+
+#include "libyang.h"
+
+#include "common.h"
+
+void
+cmd_print_help(void)
+{
+    printf("Usage: print [-f (yang | yin | tree [-q -P PATH -L LINE_LENGTH ] | info [-q -P PATH])]\n"
+            "            [-o OUTFILE] [<module-name1>[@revision]] ...\n"
+            "                  Print a schema module. The <module-name> is not required\n"
+            "                  only in case the -P option is specified.\n\n"
+            "  -f FORMAT, --format=FORMAT\n"
+            "                  Print the module in the specified FORMAT. If format not\n"
+            "                  specified, the 'tree' format is used.\n"
+            "  -L LINE_LENGTH, --tree-line-length=LINE_LENGTH\n"
+            "                 The limit of the maximum line length on which the 'tree'\n"
+            "                 format will try to be printed.\n"
+            "  -P PATH, --schema-node=PATH\n"
+            "                 Print only the specified subtree of the schema.\n"
+            "                 The PATH is the XPath subset mentioned in documentation as\n"
+            "                 the Path format. The option can be combined with --single-node\n"
+            "                 option to print information only about the specified node.\n"
+            "  -q, --single-node\n"
+            "                 Supplement to the --schema-node option to print information\n"
+            "                 only about a single node specified as PATH argument.\n"
+            "  -o OUTFILE, --output=OUTFILE\n"
+            "                  Write the output to OUTFILE instead of stdout.\n");
+}
+
+static LY_ERR
+cmd_print_submodule(struct ly_out *out, struct ly_ctx **ctx, char *name, char *revision, LYS_OUTFORMAT format, size_t line_length, uint32_t options)
+{
+    LY_ERR erc;
+    const struct lysp_submodule *submodule;
+
+    submodule = revision ?
+            ly_ctx_get_submodule(*ctx, name, revision) :
+            ly_ctx_get_submodule_latest(*ctx, name);
+
+    erc = submodule ?
+            lys_print_submodule(out, submodule, format, line_length, options) :
+            LY_ENOTFOUND;
+
+    return erc;
+}
+
+static LY_ERR
+cmd_print_module(struct ly_out *out, struct ly_ctx **ctx, char *name, char *revision, LYS_OUTFORMAT format, size_t line_length, uint32_t options)
+{
+    LY_ERR erc;
+    struct lys_module *module;
+
+    module = revision ?
+            ly_ctx_get_module(*ctx, name, revision) :
+            ly_ctx_get_module_latest(*ctx, name);
+
+    erc = module ?
+            lys_print_module(out, module, format, line_length, options) :
+            LY_ENOTFOUND;
+
+    return erc;
+}
+
+static void
+cmd_print_modules(int argc, char **argv, struct ly_out *out, struct ly_ctx **ctx, LYS_OUTFORMAT format, size_t line_length, uint32_t options)
+{
+    LY_ERR erc;
+    char *name, *revision;
+    ly_bool search_submodul;
+    const int stop = argc - optind;
+
+    for (int i = 0; i < stop; i++) {
+        name = argv[optind + i];
+        /* get revision */
+        revision = strchr(name, '@');
+        if (revision) {
+            revision[0] = '\0';
+            ++revision;
+        }
+
+        erc = cmd_print_module(out, ctx, name, revision, format, line_length, options);
+
+        if (erc == LY_ENOTFOUND) {
+            search_submodul = 1;
+            erc = cmd_print_submodule(out, ctx, name, revision, format, line_length, options);
+        } else {
+            search_submodul = 0;
+        }
+
+        if (erc == LY_SUCCESS) {
+            /* for YANG Tree Diagrams printing it's more readable to print a blank line between modules. */
+            if ((format == LYS_OUT_TREE) && (i + 1 < stop)) {
+                ly_print(out, "\n");
+            }
+            continue;
+        } else if (erc == LY_ENOTFOUND) {
+            if (revision) {
+                YLMSG_E("No (sub)module \"%s\" in revision %s found.\n", name, revision);
+            } else {
+                YLMSG_E("No (sub)module \"%s\" found.\n", name);
+            }
+            break;
+        } else {
+            if (search_submodul) {
+                YLMSG_E("Unable to print submodule %s.\n", name);
+            } else {
+                YLMSG_E("Unable to print module %s.\n", name);
+            }
+            break;
+        }
+    }
+}
+
+void
+cmd_print(struct ly_ctx **ctx, const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"format", required_argument, NULL, 'f'},
+        {"help", no_argument, NULL, 'h'},
+        {"tree-line-length", required_argument, NULL, 'L'},
+        {"output", required_argument, NULL, 'o'},
+        {"schema-node", required_argument, NULL, 'P'},
+        {"single-node", no_argument, NULL, 'q'},
+        {NULL, 0, NULL, 0}
+    };
+    uint16_t options_print = 0;
+    const char *node_path = NULL;
+    LYS_OUTFORMAT format = LYS_OUT_TREE;
+    struct ly_out *out = NULL;
+    ly_bool out_stdout = 0;
+    size_t line_length = 0;
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "f:hL:o:P:q", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'o': /* --output */
+            if (out) {
+                if (ly_out_filepath(out, optarg) != NULL) {
+                    YLMSG_E("Unable to use output file %s for printing output.\n", optarg);
+                    goto cleanup;
+                }
+            } else {
+                if (ly_out_new_filepath(optarg, &out)) {
+                    YLMSG_E("Unable to use output file %s for printing output.\n", optarg);
+                    goto cleanup;
+                }
+            }
+            break;
+
+        case 'f': /* --format */
+            if (!strcasecmp(optarg, "yang")) {
+                format = LYS_OUT_YANG;
+            } else if (!strcasecmp(optarg, "yin")) {
+                format = LYS_OUT_YIN;
+            } else if (!strcasecmp(optarg, "info")) {
+                format = LYS_OUT_YANG_COMPILED;
+            } else if (!strcasecmp(optarg, "tree")) {
+                format = LYS_OUT_TREE;
+            } else {
+                YLMSG_E("Unknown output format %s\n", optarg);
+                cmd_print_help();
+                goto cleanup;
+            }
+            break;
+
+        case 'L': /* --tree-line-length */
+            line_length = atoi(optarg);
+            break;
+
+        case 'P': /* --schema-node */
+            node_path = optarg;
+            break;
+
+        case 'q': /* --single-node */
+            options_print |= LYS_PRINT_NO_SUBSTMT;
+            break;
+
+        case 'h':
+            cmd_print_help();
+            goto cleanup;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    /* file name */
+    if ((argc == optind) && !node_path) {
+        YLMSG_E("Missing the name of the module to print.\n");
+        goto cleanup;
+    }
+
+    if ((format != LYS_OUT_TREE) && line_length) {
+        YLMSG_E("--tree-line-length take effect only in case of the tree output format.\n");
+        goto cleanup;
+    }
+
+    if (!out) {
+        if (ly_out_new_file(stdout, &out)) {
+            YLMSG_E("Could not use stdout to print output.\n");
+            goto cleanup;
+        }
+        out_stdout = 1;
+    }
+
+    if (format == LYS_OUT_TREE) {
+        /* print tree from lysc_nodes */
+        ly_ctx_set_options(*ctx, LY_CTX_SET_PRIV_PARSED);
+    }
+
+    if (node_path) {
+        const struct lysc_node *node;
+
+        node = find_schema_path(*ctx, node_path);
+        if (!node) {
+            YLMSG_E("The requested schema node \"%s\" does not exists.\n", node_path);
+            goto cleanup;
+        }
+
+        if (lys_print_node(out, node, format, 0, options_print)) {
+            YLMSG_E("Unable to print schema node %s.\n", node_path);
+            goto cleanup;
+        }
+    } else {
+        cmd_print_modules(argc, argv, out, ctx, format, line_length, options_print);
+        goto cleanup;
+    }
+
+cleanup:
+    free_cmdline(argv);
+    ly_out_free(out, NULL, out_stdout ? 0 : 1);
+}
diff --git a/tools/lint/cmd_searchpath.c b/tools/lint/cmd_searchpath.c
new file mode 100644
index 0000000..529e05d
--- /dev/null
+++ b/tools/lint/cmd_searchpath.c
@@ -0,0 +1,90 @@
+/**
+ * @file cmd_searchpath.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief 'searchpath' command of the libyang's yanglint tool.
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include "cmd.h"
+
+#include <getopt.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include "libyang.h"
+
+#include "common.h"
+
+void
+cmd_searchpath_help(void)
+{
+    printf("Usage: searchpath [--clear] [<modules-dir-path> ...]\n"
+            "                  Set paths of directories where to search for imports and\n"
+            "                  includes of the schema modules. The current working directory\n"
+            "                  and the path of the module being added is used implicitly.\n"
+            "                  The 'load' command uses these paths to search even for the\n"
+            "                  schema modules to be loaded.\n");
+}
+
+void
+cmd_searchpath(struct ly_ctx **ctx, const char *cmdline)
+{
+    int argc = 0;
+    char **argv = NULL;
+    int opt, opt_index;
+    struct option options[] = {
+        {"clear", no_argument, NULL, 'c'},
+        {"help", no_argument, NULL, 'h'},
+        {NULL, 0, NULL, 0}
+    };
+    int8_t cleared = 0;
+
+    if (parse_cmdline(cmdline, &argc, &argv)) {
+        goto cleanup;
+    }
+
+    while ((opt = getopt_long(argc, argv, "ch", options, &opt_index)) != -1) {
+        switch (opt) {
+        case 'c':
+            ly_ctx_unset_searchdir(*ctx, NULL);
+            cleared = 1;
+            break;
+        case 'h':
+            cmd_searchpath_help();
+            goto cleanup;
+        default:
+            YLMSG_E("Unknown option.\n");
+            goto cleanup;
+        }
+    }
+
+    if (!cleared && (argc == optind)) {
+        /* no argument - print the paths */
+        const char * const *dirs = ly_ctx_get_searchdirs(*ctx);
+
+        printf("List of the searchpaths:\n");
+        for (uint32_t i = 0; dirs[i]; ++i) {
+            printf("    %s\n", dirs[i]);
+        }
+        goto cleanup;
+    }
+
+    for (int i = 0; i < argc - optind; i++) {
+        if (ly_ctx_set_searchdir(*ctx, argv[optind + i])) {
+            goto cleanup;
+        }
+    }
+
+cleanup:
+    free_cmdline(argv);
+}
diff --git a/tools/lint/common.c b/tools/lint/common.c
new file mode 100644
index 0000000..fc9b1cd
--- /dev/null
+++ b/tools/lint/common.c
@@ -0,0 +1,868 @@
+/**
+ * @file common.c
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief libyang's yanglint tool - common functions for both interactive and non-interactive mode.
+ *
+ * Copyright (c) 2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+#define _POSIX_C_SOURCE 200809L /* strdup, strndup */
+
+#include "common.h"
+
+#include <assert.h>
+#include <errno.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+
+#include "compat.h"
+#include "libyang.h"
+
+int
+parse_schema_path(const char *path, char **dir, char **module)
+{
+    char *p;
+
+    assert(dir);
+    assert(module);
+
+    /* split the path to dirname and basename for further work */
+    *dir = strdup(path);
+    *module = strrchr(*dir, '/');
+    if (!(*module)) {
+        *module = *dir;
+        *dir = strdup("./");
+    } else {
+        *module[0] = '\0'; /* break the dir */
+        *module = strdup((*module) + 1);
+    }
+    /* get the pure module name without suffix or revision part of the filename */
+    if ((p = strchr(*module, '@'))) {
+        /* revision */
+        *p = '\0';
+    } else if ((p = strrchr(*module, '.'))) {
+        /* fileformat suffix */
+        *p = '\0';
+    }
+
+    return 0;
+}
+
+int
+get_input(const char *filepath, LYS_INFORMAT *format_schema, LYD_FORMAT *format_data, struct ly_in **in)
+{
+    struct stat st;
+
+    /* check that the filepath exists and is a regular file */
+    if (stat(filepath, &st) == -1) {
+        YLMSG_E("Unable to use input filepath (%s) - %s.\n", filepath, strerror(errno));
+        return -1;
+    }
+    if (!S_ISREG(st.st_mode)) {
+        YLMSG_E("Provided input file (%s) is not a regular file.\n", filepath);
+        return -1;
+    }
+
+    if ((format_schema && !*format_schema) || (format_data && !*format_data)) {
+        /* get the file format */
+        if (get_format(filepath, format_schema, format_data)) {
+            return -1;
+        }
+    }
+
+    if (ly_in_new_filepath(filepath, 0, in)) {
+        YLMSG_E("Unable to process input file.\n");
+        return -1;
+    }
+
+    return 0;
+}
+
+void
+free_features(void *flist)
+{
+    struct schema_features *rec = (struct schema_features *)flist;
+
+    if (rec) {
+        free(rec->mod_name);
+        if (rec->features) {
+            for (uint32_t u = 0; rec->features[u]; ++u) {
+                free(rec->features[u]);
+            }
+            free(rec->features);
+        }
+        free(rec);
+    }
+}
+
+void
+get_features(struct ly_set *fset, const char *module, const char ***features)
+{
+    /* get features list for this module */
+    for (uint32_t u = 0; u < fset->count; ++u) {
+        struct schema_features *sf = (struct schema_features *)fset->objs[u];
+
+        if (!strcmp(module, sf->mod_name)) {
+            /* matched module - explicitly set features */
+            *features = (const char **)sf->features;
+            sf->applied = 1;
+            return;
+        }
+    }
+
+    /* features not set so disable all */
+    *features = NULL;
+}
+
+int
+parse_features(const char *fstring, struct ly_set *fset)
+{
+    struct schema_features *rec;
+    uint32_t count;
+    char *p, **fp;
+
+    rec = calloc(1, sizeof *rec);
+    if (!rec) {
+        YLMSG_E("Unable to allocate features information record (%s).\n", strerror(errno));
+        return -1;
+    }
+    if (ly_set_add(fset, rec, 1, NULL)) {
+        YLMSG_E("Unable to store features information (%s).\n", strerror(errno));
+        free(rec);
+        return -1;
+    }
+
+    /* fill the record */
+    p = strchr(fstring, ':');
+    if (!p) {
+        YLMSG_E("Invalid format of the features specification (%s).\n", fstring);
+        return -1;
+    }
+    rec->mod_name = strndup(fstring, p - fstring);
+
+    count = 0;
+    while (p) {
+        size_t len = 0;
+        char *token = p + 1;
+
+        p = strchr(token, ',');
+        if (!p) {
+            /* the last item, if any */
+            len = strlen(token);
+        } else {
+            len = p - token;
+        }
+
+        if (len) {
+            fp = realloc(rec->features, (count + 1) * sizeof *rec->features);
+            if (!fp) {
+                YLMSG_E("Unable to store features list information (%s).\n", strerror(errno));
+                return -1;
+            }
+            rec->features = fp;
+            fp = &rec->features[count++]; /* array item to set */
+            (*fp) = strndup(token, len);
+        }
+    }
+
+    /* terminating NULL */
+    fp = realloc(rec->features, (count + 1) * sizeof *rec->features);
+    if (!fp) {
+        YLMSG_E("Unable to store features list information (%s).\n", strerror(errno));
+        return -1;
+    }
+    rec->features = fp;
+    rec->features[count++] = NULL;
+
+    return 0;
+}
+
+struct cmdline_file *
+fill_cmdline_file(struct ly_set *set, struct ly_in *in, const char *path, LYD_FORMAT format)
+{
+    struct cmdline_file *rec;
+
+    rec = malloc(sizeof *rec);
+    if (!rec) {
+        YLMSG_E("Allocating memory for data file information failed.\n");
+        return NULL;
+    }
+    rec->in = in;
+    rec->path = path;
+    rec->format = format;
+
+    if (set && ly_set_add(set, rec, 1, NULL)) {
+        free(rec);
+        YLMSG_E("Storing data file information failed.\n");
+        return NULL;
+    }
+
+    return rec;
+}
+
+int
+collect_features(const struct lys_module *mod, struct ly_set *set)
+{
+    struct lysp_feature *f = NULL;
+    uint32_t idx = 0;
+
+    while ((f = lysp_feature_next(f, mod->parsed, &idx))) {
+        if (ly_set_add(set, (void *)f->name, 1, NULL)) {
+            YLMSG_E("Memory allocation failed.\n");
+            ly_set_erase(set, NULL);
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
+void
+print_features(struct ly_out *out, const struct lys_module *mod, const struct ly_set *set)
+{
+    size_t max_len;
+    uint32_t j;
+    const char *name;
+
+    /* header */
+    ly_print(out, "%s:\n", mod->name);
+
+    /* no features */
+    if (!set->count) {
+        ly_print(out, "\t(none)\n\n");
+        return;
+    }
+
+    /* get max len, so the statuses of all the features will be aligned */
+    max_len = 0;
+    for (j = 0; j < set->count; ++j) {
+        name = set->objs[j];
+        if (strlen(name) > max_len) {
+            max_len = strlen(name);
+        }
+    }
+
+    /* print features */
+    for (j = 0; j < set->count; ++j) {
+        name = set->objs[j];
+        ly_print(out, "\t%-*s (%s)\n", (int)max_len, name, lys_feature_value(mod, name) ? "off" : "on");
+    }
+
+    ly_print(out, "\n");
+}
+
+int
+generate_features_output(const struct lys_module *mod, const struct ly_set *set, char **features_param)
+{
+    uint32_t j;
+    /*
+     * features_len - length of all the features in the current module
+     * added_len - length of a string to be added, = features_len + extra necessary length
+     * param_len - length of the parameter before appending new string
+    */
+    size_t features_len, added_len, param_len;
+    char *tmp;
+
+    features_len = 0;
+    for (j = 0; j < set->count; j++) {
+        features_len += strlen(set->objs[j]);
+    }
+
+    if (j == 0) {
+        /* no features */
+        added_len = strlen("-F ") + strlen(mod->name) + strlen(":");
+    } else {
+        /* j = comma count, -1 because of trailing comma */
+        added_len = strlen("-F ") + strlen(mod->name) + strlen(":") + features_len + j - 1;
+    }
+
+    /* to avoid strlen(NULL) if this is the first call */
+    param_len = 0;
+    if (*features_param) {
+        param_len = strlen(*features_param);
+    }
+
+    /* +1 because of white space at the beginning */
+    tmp = realloc(*features_param, param_len + added_len + 1 + 1);
+    if (!tmp) {
+        goto error;
+    } else {
+        *features_param = tmp;
+    }
+    sprintf(*features_param + param_len, " -F %s:", mod->name);
+
+    for (j = 0; j < set->count; j++) {
+        strcat(*features_param, set->objs[j]);
+        /* no trailing comma */
+        if (j != (set->count - 1)) {
+            strcat(*features_param, ",");
+        }
+    }
+
+    return 0;
+
+error:
+    YLMSG_E("Memory allocation failed (%s:%d, %s).\n", __FILE__, __LINE__, strerror(errno));
+    return 1;
+}
+
+int
+print_all_features(struct ly_out *out, const struct ly_ctx *ctx, ly_bool generate_features, char **features_param)
+{
+    int ret = 0;
+    uint32_t i = 0;
+    struct lys_module *mod;
+    struct ly_set set = {0};
+
+    while ((mod = ly_ctx_get_module_iter(ctx, &i)) != NULL) {
+        /* only care about implemented modules */
+        if (!mod->implemented) {
+            continue;
+        }
+
+        /* always erase the set, so the previous module's features don't carry over to the next module's features */
+        ly_set_erase(&set, NULL);
+
+        if (collect_features(mod, &set)) {
+            ret = 1;
+            goto cleanup;
+        }
+
+        if (generate_features && generate_features_output(mod, &set, features_param)) {
+            ret = 1;
+            goto cleanup;
+        }
+        print_features(out, mod, &set);
+    }
+
+cleanup:
+    ly_set_erase(&set, NULL);
+    return ret;
+}
+
+void
+free_cmdline_file(void *cmdline_file)
+{
+    struct cmdline_file *rec = (struct cmdline_file *)cmdline_file;
+
+    if (rec) {
+        ly_in_free(rec->in, 1);
+        free(rec);
+    }
+}
+
+void
+free_cmdline(char *argv[])
+{
+    if (argv) {
+        free(argv[0]);
+        free(argv);
+    }
+}
+
+int
+parse_cmdline(const char *cmdline, int *argc_p, char **argv_p[])
+{
+    int count;
+    char **vector;
+    char *ptr;
+    char qmark = 0;
+
+    assert(cmdline);
+    assert(argc_p);
+    assert(argv_p);
+
+    /* init */
+    optind = 0; /* reinitialize getopt() */
+    count = 1;
+    vector = malloc((count + 1) * sizeof *vector);
+    vector[0] = strdup(cmdline);
+
+    /* command name */
+    strtok(vector[0], " ");
+
+    /* arguments */
+    while ((ptr = strtok(NULL, " "))) {
+        size_t len;
+        void *r;
+
+        len = strlen(ptr);
+
+        if (qmark) {
+            /* still in quotated text */
+            /* remove NULL termination of the previous token since it is not a token,
+             * but a part of the quotation string */
+            ptr[-1] = ' ';
+
+            if ((ptr[len - 1] == qmark) && (ptr[len - 2] != '\\')) {
+                /* end of quotation */
+                qmark = 0;
+                /* shorten the argument by the terminating quotation mark */
+                ptr[len - 1] = '\0';
+            }
+            continue;
+        }
+
+        /* another token in cmdline */
+        ++count;
+        r = realloc(vector, (count + 1) * sizeof *vector);
+        if (!r) {
+            YLMSG_E("Memory allocation failed (%s:%d, %s).\n", __FILE__, __LINE__, strerror(errno));
+            free(vector);
+            return -1;
+        }
+        vector = r;
+        vector[count - 1] = ptr;
+
+        if ((ptr[0] == '"') || (ptr[0] == '\'')) {
+            /* remember the quotation mark to identify end of quotation */
+            qmark = ptr[0];
+
+            /* move the remembered argument after the quotation mark */
+            ++vector[count - 1];
+
+            /* check if the quotation is terminated within this token */
+            if ((ptr[len - 1] == qmark) && (ptr[len - 2] != '\\')) {
+                /* end of quotation */
+                qmark = 0;
+                /* shorten the argument by the terminating quotation mark */
+                ptr[len - 1] = '\0';
+            }
+        }
+    }
+    vector[count] = NULL;
+
+    *argc_p = count;
+    *argv_p = vector;
+
+    return 0;
+}
+
+int
+get_format(const char *filename, LYS_INFORMAT *schema, LYD_FORMAT *data)
+{
+    char *ptr;
+    LYS_INFORMAT informat_s;
+    LYD_FORMAT informat_d;
+
+    /* get the file format */
+    if ((ptr = strrchr(filename, '.')) != NULL) {
+        ++ptr;
+        if (!strcmp(ptr, "yang")) {
+            informat_s = LYS_IN_YANG;
+            informat_d = 0;
+        } else if (!strcmp(ptr, "yin")) {
+            informat_s = LYS_IN_YIN;
+            informat_d = 0;
+        } else if (!strcmp(ptr, "xml")) {
+            informat_s = 0;
+            informat_d = LYD_XML;
+        } else if (!strcmp(ptr, "json")) {
+            informat_s = 0;
+            informat_d = LYD_JSON;
+        } else if (!strcmp(ptr, "lyb")) {
+            informat_s = 0;
+            informat_d = LYD_LYB;
+        } else {
+            YLMSG_E("Input file \"%s\" in an unknown format \"%s\".\n", filename, ptr);
+            return 0;
+        }
+    } else {
+        YLMSG_E("Input file \"%s\" without file extension - unknown format.\n", filename);
+        return 1;
+    }
+
+    if (informat_d) {
+        if (!data) {
+            YLMSG_E("Input file \"%s\" not expected to contain data instances (unexpected format).\n", filename);
+            return 2;
+        }
+        (*data) = informat_d;
+    } else if (informat_s) {
+        if (!schema) {
+            YLMSG_E("Input file \"%s\" not expected to contain schema definition (unexpected format).\n", filename);
+            return 3;
+        }
+        (*schema) = informat_s;
+    }
+
+    return 0;
+}
+
+int
+print_list(struct ly_out *out, struct ly_ctx *ctx, LYD_FORMAT outformat)
+{
+    struct lyd_node *ylib;
+    uint32_t idx = 0, has_modules = 0;
+    const struct lys_module *mod;
+
+    if (outformat != LYD_UNKNOWN) {
+        if (ly_ctx_get_yanglib_data(ctx, &ylib, "%u", ly_ctx_get_change_count(ctx))) {
+            YLMSG_E("Getting context info (ietf-yang-library data) failed. If the YANG module is missing or not implemented, use an option to add it internally.\n");
+            return 1;
+        }
+
+        lyd_print_all(out, ylib, outformat, 0);
+        lyd_free_all(ylib);
+        return 0;
+    }
+
+    /* iterate schemas in context and provide just the basic info */
+    ly_print(out, "List of the loaded models:\n");
+    while ((mod = ly_ctx_get_module_iter(ctx, &idx))) {
+        has_modules++;
+
+        /* conformance print */
+        if (mod->implemented) {
+            ly_print(out, "    I");
+        } else {
+            ly_print(out, "    i");
+        }
+
+        /* module print */
+        ly_print(out, " %s", mod->name);
+        if (mod->revision) {
+            ly_print(out, "@%s", mod->revision);
+        }
+
+        /* submodules print */
+        if (mod->parsed && mod->parsed->includes) {
+            uint64_t u = 0;
+
+            ly_print(out, " (");
+            LY_ARRAY_FOR(mod->parsed->includes, u) {
+                ly_print(out, "%s%s", !u ? "" : ",", mod->parsed->includes[u].name);
+                if (mod->parsed->includes[u].rev[0]) {
+                    ly_print(out, "@%s", mod->parsed->includes[u].rev);
+                }
+            }
+            ly_print(out, ")");
+        }
+
+        /* finish the line */
+        ly_print(out, "\n");
+    }
+
+    if (!has_modules) {
+        ly_print(out, "\t(none)\n");
+    }
+
+    ly_print_flush(out);
+    return 0;
+}
+
+int
+evaluate_xpath(const struct lyd_node *tree, const char *xpath)
+{
+    struct ly_set *set = NULL;
+
+    if (lyd_find_xpath(tree, xpath, &set)) {
+        return -1;
+    }
+
+    /* print result */
+    printf("XPath \"%s\" evaluation result:\n", xpath);
+    if (!set->count) {
+        printf("\tEmpty\n");
+    } else {
+        for (uint32_t u = 0; u < set->count; ++u) {
+            struct lyd_node *node = (struct lyd_node *)set->objs[u];
+
+            printf("  %s \"%s\"", lys_nodetype2str(node->schema->nodetype), node->schema->name);
+            if (node->schema->nodetype & (LYS_LEAF | LYS_LEAFLIST)) {
+                printf(" (value: \"%s\")\n", lyd_get_value(node));
+            } else if (node->schema->nodetype == LYS_LIST) {
+                printf(" (");
+                for (struct lyd_node *key = ((struct lyd_node_inner *)node)->child; key && lysc_is_key(key->schema); key = key->next) {
+                    printf("%s\"%s\": \"%s\";", (key != ((struct lyd_node_inner *)node)->child) ? " " : "",
+                            key->schema->name, lyd_get_value(key));
+                }
+                printf(")\n");
+            }
+        }
+    }
+
+    ly_set_free(set, NULL);
+    return 0;
+}
+
+LY_ERR
+process_data(struct ly_ctx *ctx, enum lyd_type data_type, uint8_t merge, LYD_FORMAT format, struct ly_out *out,
+        uint32_t options_parse, uint32_t options_validate, uint32_t options_print, struct cmdline_file *operational_f,
+        struct cmdline_file *rpc_f, struct ly_set *inputs, struct ly_set *xpaths)
+{
+    LY_ERR ret = LY_SUCCESS;
+    struct lyd_node *tree = NULL, *op = NULL, *envp = NULL, *merged_tree = NULL, *oper_tree = NULL;
+    char *path = NULL;
+    struct ly_set *set = NULL;
+
+    /* additional operational datastore */
+    if (operational_f && operational_f->in) {
+        ret = lyd_parse_data(ctx, NULL, operational_f->in, operational_f->format, LYD_PARSE_ONLY, 0, &oper_tree);
+        if (ret) {
+            YLMSG_E("Failed to parse operational datastore file \"%s\".\n", operational_f->path);
+            goto cleanup;
+        }
+    }
+
+    for (uint32_t u = 0; u < inputs->count; ++u) {
+        struct cmdline_file *input_f = (struct cmdline_file *)inputs->objs[u];
+
+        switch (data_type) {
+        case LYD_TYPE_DATA_YANG:
+            ret = lyd_parse_data(ctx, NULL, input_f->in, input_f->format, options_parse, options_validate, &tree);
+            break;
+        case LYD_TYPE_RPC_YANG:
+        case LYD_TYPE_REPLY_YANG:
+        case LYD_TYPE_NOTIF_YANG:
+            ret = lyd_parse_op(ctx, NULL, input_f->in, input_f->format, data_type, &tree, &op);
+            break;
+        case LYD_TYPE_RPC_NETCONF:
+        case LYD_TYPE_NOTIF_NETCONF:
+            ret = lyd_parse_op(ctx, NULL, input_f->in, input_f->format, data_type, &envp, &op);
+
+            /* adjust pointers */
+            for (tree = op; lyd_parent(tree); tree = lyd_parent(tree)) {}
+            break;
+        case LYD_TYPE_REPLY_NETCONF:
+            /* parse source RPC operation */
+            assert(rpc_f && rpc_f->in);
+            ret = lyd_parse_op(ctx, NULL, rpc_f->in, rpc_f->format, LYD_TYPE_RPC_NETCONF, &envp, &op);
+            if (ret) {
+                YLMSG_E("Failed to parse source NETCONF RPC operation file \"%s\".\n", rpc_f->path);
+                goto cleanup;
+            }
+
+            /* adjust pointers */
+            for (tree = op; lyd_parent(tree); tree = lyd_parent(tree)) {}
+
+            /* free input */
+            lyd_free_siblings(lyd_child(op));
+
+            /* we do not care */
+            lyd_free_all(envp);
+            envp = NULL;
+
+            ret = lyd_parse_op(ctx, op, input_f->in, input_f->format, data_type, &envp, NULL);
+            break;
+        default:
+            YLMSG_E("Internal error (%s:%d).\n", __FILE__, __LINE__);
+            goto cleanup;
+        }
+
+        if (ret) {
+            YLMSG_E("Failed to parse input data file \"%s\".\n", input_f->path);
+            goto cleanup;
+        }
+
+        if (merge) {
+            /* merge the data so far parsed for later validation and print */
+            if (!merged_tree) {
+                merged_tree = tree;
+            } else {
+                ret = lyd_merge_siblings(&merged_tree, tree, LYD_MERGE_DESTRUCT);
+                if (ret) {
+                    YLMSG_E("Merging %s with previous data failed.\n", input_f->path);
+                    goto cleanup;
+                }
+            }
+            tree = NULL;
+        } else if (format) {
+            /* print */
+            switch (data_type) {
+            case LYD_TYPE_DATA_YANG:
+                lyd_print_all(out, tree, format, options_print);
+                break;
+            case LYD_TYPE_RPC_YANG:
+            case LYD_TYPE_REPLY_YANG:
+            case LYD_TYPE_NOTIF_YANG:
+            case LYD_TYPE_RPC_NETCONF:
+            case LYD_TYPE_NOTIF_NETCONF:
+                lyd_print_tree(out, tree, format, options_print);
+                break;
+            case LYD_TYPE_REPLY_NETCONF:
+                /* just the output */
+                lyd_print_tree(out, lyd_child(tree), format, options_print);
+                break;
+            default:
+                assert(0);
+            }
+        } else {
+            /* validation of the RPC/Action/reply/Notification with the operational datastore, if any */
+            switch (data_type) {
+            case LYD_TYPE_DATA_YANG:
+                /* already validated */
+                break;
+            case LYD_TYPE_RPC_YANG:
+            case LYD_TYPE_RPC_NETCONF:
+                ret = lyd_validate_op(tree, oper_tree, LYD_TYPE_RPC_YANG, NULL);
+                break;
+            case LYD_TYPE_REPLY_YANG:
+            case LYD_TYPE_REPLY_NETCONF:
+                ret = lyd_validate_op(tree, oper_tree, LYD_TYPE_REPLY_YANG, NULL);
+                break;
+            case LYD_TYPE_NOTIF_YANG:
+            case LYD_TYPE_NOTIF_NETCONF:
+                ret = lyd_validate_op(tree, oper_tree, LYD_TYPE_NOTIF_YANG, NULL);
+                break;
+            default:
+                assert(0);
+            }
+            if (ret) {
+                if (operational_f->path) {
+                    YLMSG_E("Failed to validate input data file \"%s\" with operational datastore \"%s\".\n",
+                            input_f->path, operational_f->path);
+                } else {
+                    YLMSG_E("Failed to validate input data file \"%s\".\n", input_f->path);
+                }
+                goto cleanup;
+            }
+
+            if (op && oper_tree && lyd_parent(op)) {
+                /* check operation parent existence */
+                path = lyd_path(lyd_parent(op), LYD_PATH_STD, NULL, 0);
+                if (!path) {
+                    ret = LY_EMEM;
+                    goto cleanup;
+                }
+                if ((ret = lyd_find_xpath(oper_tree, path, &set))) {
+                    goto cleanup;
+                }
+                if (!set->count) {
+                    YLMSG_E("Operation \"%s\" parent \"%s\" not found in the operational data.\n", LYD_NAME(op), path);
+                    ret = LY_EVALID;
+                    goto cleanup;
+                }
+            }
+        }
+
+        /* next iter */
+        lyd_free_all(tree);
+        tree = NULL;
+        lyd_free_all(envp);
+        envp = NULL;
+    }
+
+    if (merge) {
+        /* validate the merged result */
+        ret = lyd_validate_all(&merged_tree, ctx, LYD_VALIDATE_PRESENT, NULL);
+        if (ret) {
+            YLMSG_E("Merged data are not valid.\n");
+            goto cleanup;
+        }
+
+        if (format) {
+            /* and print it */
+            lyd_print_all(out, merged_tree, format, options_print);
+        }
+
+        for (uint32_t u = 0; xpaths && (u < xpaths->count); ++u) {
+            if (evaluate_xpath(merged_tree, (const char *)xpaths->objs[u])) {
+                goto cleanup;
+            }
+        }
+    }
+
+cleanup:
+    lyd_free_all(tree);
+    lyd_free_all(envp);
+    lyd_free_all(merged_tree);
+    lyd_free_all(oper_tree);
+    free(path);
+    ly_set_free(set, NULL);
+    return ret;
+}
+
+const struct lysc_node *
+find_schema_path(const struct ly_ctx *ctx, const char *schema_path)
+{
+    const char *end, *module_name_end;
+    char *module_name = NULL;
+    const struct lysc_node *node = NULL, *parent_node = NULL, *parent_node_tmp = NULL;
+    const struct lys_module *module;
+    size_t node_name_len;
+    ly_bool found_exact_match = 0;
+
+    /* iterate over each '/' in the path */
+    while (schema_path) {
+        /* example: schema_path = /listen/endpoint
+         * end == NULL for endpoint, end exists for listen */
+        end = strchr(schema_path + 1, '/');
+        if (end) {
+            node_name_len = end - schema_path - 1;
+        } else {
+            node_name_len = strlen(schema_path + 1);
+        }
+
+        /* ex: schema_path = /ietf-interfaces:interfaces/interface/ietf-ip:ipv4 */
+        module_name_end = strchr(schema_path, ':');
+        if (module_name_end && (!end || (module_name_end < end))) {
+            /* only get module's name, if it is in the current scope */
+            free(module_name);
+            /* - 1 because module_name_end points to ':' */
+            module_name = strndup(schema_path + 1, module_name_end - schema_path - 1);
+            if (!module_name) {
+                YLMSG_E("Memory allocation failed (%s:%d, %s)", __FILE__, __LINE__, strerror(errno));
+                parent_node = NULL;
+                goto cleanup;
+            }
+            /* move the pointer to the beginning of the node's name - 1 */
+            schema_path = module_name_end;
+
+            /* recalculate the length of the node's name, because the module prefix mustn't be compared later */
+            if (module_name_end < end) {
+                node_name_len = end - module_name_end - 1;
+            } else if (!end) {
+                node_name_len = strlen(module_name_end + 1);
+            }
+        }
+
+        module = ly_ctx_get_module_implemented(ctx, module_name);
+        if (!module) {
+            /* unknown module name */
+            parent_node = NULL;
+            goto cleanup;
+        }
+
+        /* iterate over the node's siblings / module's top level containers */
+        while ((node = lys_getnext(node, parent_node, module->compiled, LYS_GETNEXT_WITHCASE | LYS_GETNEXT_WITHCHOICE))) {
+            if (end && !strncmp(node->name, schema_path + 1, node_name_len) && (node->name[node_name_len] == '\0')) {
+                /* check if the whole node's name matches and it's not just a common prefix */
+                parent_node = node;
+                break;
+            } else if (!strncmp(node->name, schema_path + 1, node_name_len)) {
+                /* do the same here, however if there is no exact match, use the last node with the same prefix */
+                if (strlen(node->name) == node_name_len) {
+                    parent_node = node;
+                    found_exact_match = 1;
+                    break;
+                } else {
+                    parent_node_tmp = node;
+                }
+            }
+        }
+
+        if (!end && !found_exact_match) {
+            /* no exact match */
+            parent_node = parent_node_tmp;
+        }
+        found_exact_match = 0;
+
+        /* next iter */
+        schema_path = strchr(schema_path + 1, '/');
+    }
+
+cleanup:
+    free(module_name);
+    return parent_node;
+}
diff --git a/tools/lint/common.h b/tools/lint/common.h
new file mode 100644
index 0000000..7c6a8ad
--- /dev/null
+++ b/tools/lint/common.h
@@ -0,0 +1,257 @@
+/**
+ * @file common.h
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief libyang's yanglint tool - common functions and definitions for both interactive and non-interactive mode.
+ *
+ * Copyright (c) 2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#ifndef COMMON_H_
+#define COMMON_H_
+
+#include <stdint.h>
+#include <stdio.h>
+
+#include "libyang.h"
+
+#define PROMPT "> "
+
+/**
+ * @brief Default context creation options.
+ */
+#define YL_DEFAULT_CTX_OPTIONS LY_CTX_NO_YANGLIBRARY
+
+/**
+ * @brief Default data parsing flags.
+ */
+#define YL_DEFAULT_DATA_PARSE_OPTIONS LYD_PARSE_STRICT
+
+/**
+ * @brief log error message
+ */
+#define YLMSG_E(...) \
+        fprintf(stderr, "YANGLINT[E]: " __VA_ARGS__)
+
+/**
+ * @brief log warning message
+ */
+#define YLMSG_W(...) \
+        fprintf(stderr, "YANGLINT[W]: " __VA_ARGS__)
+
+#ifndef _WIN32
+# define PATH_SEPARATOR ":"
+#else
+# define PATH_SEPARATOR ";"
+#endif
+
+/**
+ * @brief Storage for the list of the features (their names) in a specific YANG module.
+ */
+struct schema_features {
+    char *mod_name;
+    char **features;
+    ly_bool applied;
+};
+
+/**
+ * @brief Data connected with a file provided on a command line as a file path.
+ */
+struct cmdline_file {
+    struct ly_in *in;
+    const char *path;
+    LYD_FORMAT format;
+};
+
+/**
+ * @brief Free the schema features list (struct schema_features *)
+ * @param[in,out] flist The (struct schema_features *) to free.
+ */
+void free_features(void *flist);
+
+/**
+ * @brief Get the list of features connected with the specific YANG module.
+ *
+ * @param[in] fset The set of features information (struct schema_features *).
+ * @param[in] module Name of the YANG module which features should be found.
+ * @param[out] features Pointer to the list of features being returned.
+ */
+void get_features(struct ly_set *fset, const char *module, const char ***features);
+
+/**
+ * @brief Parse features being specified for the specific YANG module.
+ *
+ * Format of the input @p fstring is as follows: <module_name>:[<feature>,]*
+ *
+ * @param[in] fstring Input string to be parsed.
+ * @param[in, out] fset Features information set (of struct schema_features *). The set is being filled.
+ */
+int parse_features(const char *fstring, struct ly_set *fset);
+
+/**
+ * @brief Collect all features of a module.
+ *
+ * @param[in] mod Module to be searched for features.
+ * @param[out] set Set in which the features will be stored.
+ * @return 0 on success.
+ * @return 1 on error.
+ */
+int collect_features(const struct lys_module *mod, struct ly_set *set);
+
+/**
+ * @brief Print all features of a single module.
+ *
+ * @param[in] out The output handler for printing.
+ * @param[in] mod Module which contains the features.
+ * @param[in] set Set which holds the features.
+ */
+void print_features(struct ly_out *out, const struct lys_module *mod, const struct ly_set *set);
+
+/**
+ * @brief Generate a string, which will contain features paramater.
+ *
+ * @param[in] mod Module, for which the string will be generated.
+ * @param[in] set Set containing the features.
+ * @param[out] features_param String which will contain the output.
+ * @return 0 on success.
+ * @return 1 on error.
+ */
+int generate_features_output(const struct lys_module *mod, const struct ly_set *set, char **features_param);
+
+/**
+ * @brief Print all features of all implemented modules.
+ *
+ * @param[in] out The output handler for printing.
+ * @param[in] ctx Libyang context.
+ * @param[in] generate_features Flag expressing whether to generate features parameter.
+ * @param[out] features_param String, which will contain the output if the above flag is set.
+ * @return 0 on success.
+ * @return 1 on error.
+ */
+int print_all_features(struct ly_out *out, const struct ly_ctx *ctx, ly_bool generate_features, char **features_param);
+
+/**
+ * @brief Parse path of a schema module file into the directory and module name.
+ *
+ * @param[in] path Schema module file path to be parsed.
+ * @param[out] dir Pointer to the directory path where the file resides. Caller is expected to free the returned string.
+ * @param[out] module Pointer to the name of the module (without file suffixes or revision information) specified by the
+ * @path. Caller is expected to free the returned string.
+ * @return 0 on success
+ * @return -1 on error
+ */
+int parse_schema_path(const char *path, char **dir, char **module);
+
+/**
+ * @brief Get input handler for the specified path.
+ *
+ * Using the @p format_schema and @p format_data the type of the file can be limited (by providing NULL) or it can be
+ * got known if both types are possible.
+ *
+ * @param[in] filepath Path of the file to open.
+ * @param[out] format_schema Format of the schema detected from the file name. If NULL specified, the schema formats are
+ * prohibited and such files are refused.
+ * @param[out] format_data Format of the data detected from the file name. If NULL specified, the data formats are
+ * prohibited and such files are refused.
+ * @param[out] in Created input handler referring the file behind the @p filepath.
+ * @return 0 on success.
+ * @return -1 on failure.
+ */
+int get_input(const char *filepath, LYS_INFORMAT *format_schema, LYD_FORMAT *format_data, struct ly_in **in);
+
+/**
+ * @brief Free the command line file data (struct cmdline_file *)
+ * @param[in,out] cmdline_file The (struct cmdline_file *) to free.
+ */
+void free_cmdline_file(void *cmdline_file);
+
+/**
+ * @brief Create and fill the command line file data (struct cmdline_file *).
+ * @param[in] set Optional parameter in case the record is supposed to be added into a set.
+ * @param[in] in Input file handler.
+ * @param[in] path Filepath of the file.
+ * @param[in] format Format of the data file.
+ * @return The created command line file structure.
+ * @return NULL on failure
+ */
+struct cmdline_file *fill_cmdline_file(struct ly_set *set, struct ly_in *in, const char *path, LYD_FORMAT format);
+
+/**
+ * @brief Helper function to prepare argc, argv pair from a command line string.
+ *
+ * @param[in] cmdline Complete command line string.
+ * @param[out] argc_p Pointer to store argc value.
+ * @param[out] argv_p Pointer to store argv vector.
+ * @return 0 on success, non-zero on failure.
+ */
+int parse_cmdline(const char *cmdline, int *argc_p, char **argv_p[]);
+
+/**
+ * @brief Destructor for the argument vector prepared by ::parse_cmdline().
+ *
+ * @param[in,out] argv Argument vector to destroy.
+ */
+void free_cmdline(char *argv[]);
+
+/**
+ * @brief Get expected format of the @p filename's content according to the @p filename's suffix.
+ * @param[in] filename Name of the file to examine.
+ * @param[out] schema Pointer to a variable to store the expected input schema format. Do not provide the pointer in case a
+ * schema format is not expected.
+ * @param[out] data Pointer to a variable to store the expected input data format. Do not provide the pointer in case a data
+ * format is not expected.
+ * @return zero in case a format was successfully detected.
+ * @return nonzero in case it is not possible to get valid format from the @p filename.
+ */
+int get_format(const char *filename, LYS_INFORMAT *schema, LYD_FORMAT *data);
+
+/**
+ * @brief Print list of schemas in the context.
+ *
+ * @param[in] out Output handler where to print.
+ * @param[in] ctx Context to print.
+ * @param[in] outformat Optional output format. If not specified (:LYD_UNKNOWN), a simple list with single module per line
+ * is printed. Otherwise, the ietf-yang-library data are printed in the specified format.
+ * @return zero in case the data successfully printed.
+ * @return nonzero in case of error.
+ */
+int print_list(struct ly_out *out, struct ly_ctx *ctx, LYD_FORMAT outformat);
+
+/**
+ * @brief Process the input data files - parse, validate and print according to provided options.
+ *
+ * @param[in] ctx libyang context with schema.
+ * @param[in] data_type The type of data in the input files.
+ * @param[in] merge Flag if the data should be merged before validation.
+ * @param[in] format Data format for printing.
+ * @param[in] out The output handler for printing.
+ * @param[in] options_parse Parser options.
+ * @param[in] options_validate Validation options.
+ * @param[in] options_print Printer options.
+ * @param[in] operational_f Optional operational datastore file information for the case of an extended validation of
+ * operation(s).
+ * @param[in] rpc_f Source RPC operation file information for parsing NETCONF rpc-reply.
+ * @param[in] inputs Set of file informations of input data files.
+ * @param[in] xpath The set of XPaths to be evaluated on the processed data tree, basic information about the resulting set
+ * is printed. Alternative to data printing.
+ * @return LY_ERR value.
+ */
+LY_ERR process_data(struct ly_ctx *ctx, enum lyd_type data_type, uint8_t merge, LYD_FORMAT format, struct ly_out *out,
+        uint32_t options_parse, uint32_t options_validate, uint32_t options_print, struct cmdline_file *operational_f,
+        struct cmdline_file *rpc_f, struct ly_set *inputs, struct ly_set *xpaths);
+
+/**
+ * @brief Get the node specified by the path.
+ *
+ * @param[in] ctx libyang context with schema.
+ * @param[in] schema_path Path to the wanted node.
+ * @return Pointer to the schema node specified by the path on success, NULL otherwise.
+ */
+const struct lysc_node * find_schema_path(const struct ly_ctx *ctx, const char *schema_path);
+
+#endif /* COMMON_H_ */
diff --git a/tools/lint/completion.c b/tools/lint/completion.c
new file mode 100644
index 0000000..9843816
--- /dev/null
+++ b/tools/lint/completion.c
@@ -0,0 +1,379 @@
+/**
+ * @file completion.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @brief libyang's yanglint tool auto completion
+ *
+ * Copyright (c) 2015 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+#define _POSIX_C_SOURCE 200809L /* strdup */
+
+#include <errno.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "libyang.h"
+
+#include "cmd.h"
+#include "common.h"
+#include "compat.h"
+#include "linenoise/linenoise.h"
+
+/* from the main.c */
+extern struct ly_ctx *ctx;
+
+/**
+ * @brief Add a match to the completions array.
+ *
+ * @param[in] match Match to be added.
+ * @param[in,out] matches Matches provided to the user as a completion hint.
+ * @param[in,out] match_count Number of matches.
+ */
+static void
+cmd_completion_add_match(const char *match, char ***matches, unsigned int *match_count)
+{
+    void *p;
+
+    ++(*match_count);
+    p = realloc(*matches, *match_count * sizeof **matches);
+    if (!p) {
+        YLMSG_E("Memory allocation failed (%s:%d, %s)", __FILE__, __LINE__, strerror(errno));
+        return;
+    }
+    *matches = p;
+    (*matches)[*match_count - 1] = strdup(match);
+}
+
+/**
+ * @brief Provides completion for command names.
+ *
+ * @param[in] hint User input.
+ * @param[out] matches Matches provided to the user as a completion hint.
+ * @param[out] match_count Number of matches.
+ */
+static void
+get_cmd_completion(const char *hint, char ***matches, unsigned int *match_count)
+{
+    int i;
+
+    *match_count = 0;
+    *matches = NULL;
+
+    for (i = 0; commands[i].name; i++) {
+        if (!strncmp(hint, commands[i].name, strlen(hint))) {
+            cmd_completion_add_match(commands[i].name, matches, match_count);
+        }
+    }
+}
+
+/**
+ * @brief Provides completion for module names.
+ *
+ * @param[in] hint User input.
+ * @param[out] matches Matches provided to the user as a completion hint.
+ * @param[out] match_count Number of matches.
+ */
+static void
+get_model_completion(const char *hint, char ***matches, unsigned int *match_count)
+{
+    LY_ARRAY_COUNT_TYPE u;
+    uint32_t idx = 0;
+    const struct lys_module *module;
+
+    *match_count = 0;
+    *matches = NULL;
+
+    while ((module = ly_ctx_get_module_iter(ctx, &idx))) {
+        if (!strncmp(hint, module->name, strlen(hint))) {
+            cmd_completion_add_match(module->name, matches, match_count);
+        }
+
+        LY_ARRAY_FOR(module->parsed->includes, u) {
+            if (!strncmp(hint, module->parsed->includes[u].submodule->name, strlen(hint))) {
+                cmd_completion_add_match(module->parsed->includes[u].submodule->name, matches, match_count);
+            }
+        }
+    }
+}
+
+/**
+ * @brief Add all child nodes of a single node to the completion hint.
+ *
+ * @param[in] last_node Node of which children will be added to the hint.
+ * @param matches[out] Matches provided to the user as a completion hint.
+ * @param match_count[out] Number of matches.
+ */
+static void
+single_hint_add_children(const struct lysc_node *last_node, char ***matches, unsigned int *match_count)
+{
+    const struct lysc_node *node = NULL;
+    char *match;
+
+    if (!last_node) {
+        return;
+    }
+
+    while ((node = lys_getnext(node, last_node, NULL, LYS_GETNEXT_WITHCASE | LYS_GETNEXT_WITHCHOICE))) {
+        match = lysc_path(node, LYSC_PATH_LOG, NULL, 0);
+        cmd_completion_add_match(match, matches, match_count);
+        free(match);
+    }
+}
+
+/**
+ * @brief Add module and/or node's children names to the hint.
+ *
+ * @param[in] module Compiled schema module.
+ * @param[in] parent Parent node of which children are potential matches.
+ * @param[in] hint_node_name Node name contained within the hint specified by user.
+ * @param[in,out] matches Matches provided to the user as a completion hint.
+ * @param[in,out] match_count Number of matches.
+ * @param[out] last_node Last processed node.
+ */
+static void
+add_all_children_nodes(const struct lysc_module *module, const struct lysc_node *parent,
+        const char *hint_node_name, char ***matches, unsigned int *match_count, const struct lysc_node **last_node)
+{
+    const struct lysc_node *node;
+    char *match, *node_name = NULL;
+
+    *last_node = NULL;
+
+    if (!parent && !module) {
+        return;
+    }
+
+    node = NULL;
+    while ((node = lys_getnext(node, parent, module, LYS_GETNEXT_WITHCASE | LYS_GETNEXT_WITHCHOICE))) {
+        if (parent && (node->module != parent->module)) {
+            /* augmented node */
+            if (asprintf(&node_name, "%s:%s", node->module->name, node->name) == -1) {
+                YLMSG_E("Memory allocation failed (%s:%d, %s)", __FILE__, __LINE__, strerror(errno));
+                break;
+            }
+        } else {
+            node_name = strdup(node->name);
+            if (!node_name) {
+                YLMSG_E("Memory allocation failed (%s:%d, %s)", __FILE__, __LINE__, strerror(errno));
+                break;
+            }
+        }
+        if (!hint_node_name || !strncmp(hint_node_name, node_name, strlen(hint_node_name))) {
+            /* adding just module names + their top level node(s) to the hint */
+            *last_node = node;
+            match = lysc_path(node, LYSC_PATH_LOG, NULL, 0);
+            cmd_completion_add_match(match, matches, match_count);
+            free(match);
+        }
+        free(node_name);
+    }
+}
+
+/**
+ * @brief Provides completion for schemas.
+ *
+ * @param[in] hint User input.
+ * @param[out] matches Matches provided to the user as a completion hint.
+ * @param[out] match_count Number of matches.
+ */
+static void
+get_schema_completion(const char *hint, char ***matches, unsigned int *match_count)
+{
+    const struct lys_module *module;
+    uint32_t idx;
+    const char *start;
+    char *end, *module_name = NULL, *path = NULL;
+    const struct lysc_node *parent, *last_node;
+    int rc = 0;
+    size_t len;
+
+    *match_count = 0;
+    *matches = NULL;
+
+    if (strlen(hint)) {
+        if (hint[0] != '/') {
+            return;
+        }
+        start = hint + 1;
+    } else {
+        start = hint;
+    }
+
+    end = strchr(start, ':');
+    if (!end) {
+        /* no module name */
+        len = strlen(start);
+
+        /* go through all the modules */
+        idx = 0;
+        while ((module = ly_ctx_get_module_iter(ctx, &idx))) {
+            if (!module->implemented) {
+                continue;
+            }
+
+            if (!len || !strncmp(start, module->name, len)) {
+                /* add all their (matching) top level nodes */
+                add_all_children_nodes(module->compiled, NULL, NULL, matches, match_count, &last_node);
+            }
+        }
+    } else {
+        /* module name known */
+        module_name = strndup(start, end - start);
+        if (!module_name) {
+            YLMSG_E("Memory allocation failed (%s:%d, %s)", __FILE__, __LINE__, strerror(errno));
+            rc = 1;
+            goto cleanup;
+        }
+
+        module = ly_ctx_get_module_implemented(ctx, module_name);
+        if (!module) {
+            goto cleanup;
+        }
+
+        /* find the last '/', if it is at the beginning of the hint, only path up to the top level node is known,
+         * else the name of the last node starts after the found '/' */
+        start = strrchr(hint, '/');
+        if (!start) {
+            goto cleanup;
+        }
+
+        if (start == hint) {
+            /* only the (incomplete) top level node path, add all (matching) top level nodes */
+            add_all_children_nodes(module->compiled, NULL, end + 1, matches, match_count, &last_node);
+            goto cleanup;
+        }
+
+        /* get rid of stuff after the last '/' to obtain the parent node */
+        path = strndup(hint, start - hint);
+        if (!path) {
+            YLMSG_E("Memory allocation failed (%s:%d, %s)", __FILE__, __LINE__, strerror(errno));
+            rc = 1;
+            goto cleanup;
+        }
+
+        /* get the last parent in the hint (it may not exist) */
+        parent = find_schema_path(ctx, path);
+
+        /* add all (matching) child nodes of the parent */
+        add_all_children_nodes(NULL, parent, start + 1, matches, match_count, &last_node);
+    }
+
+cleanup:
+    if (!rc && (*match_count == 1)) {
+        /* to avoid a single hint (space at the end), add all children as hints */
+        single_hint_add_children(last_node, matches, match_count);
+    }
+    free(path);
+    free(module_name);
+}
+
+/**
+ * @brief Get the string before the hint, which autocompletion is for.
+ *
+ * @param[in] buf Complete user input.
+ * @param[in] hint Hint part of the user input.
+ * @return Pointer to the last string.
+ */
+static const char *
+get_last_str(const char *buf, const char *hint)
+{
+    const char *ptr;
+
+    if (buf == hint) {
+        return buf;
+    }
+
+    ptr = hint - 1;
+    while (ptr[0] == ' ') {
+        --ptr;
+        if (buf == ptr) {
+            return buf;
+        }
+    }
+
+    while (ptr[-1] != ' ') {
+        --ptr;
+        if (buf == ptr) {
+            return buf;
+        }
+    }
+
+    return ptr;
+}
+
+/* callback */
+void
+complete_cmd(const char *buf, const char *hint, linenoiseCompletions *lc)
+{
+    struct autocomplete {
+        const char *cmd;    /**< command */
+        const char *opt;    /**< optional option */
+        int last_opt;       /**< whether to autocomplete even if an option is last in the hint */
+
+        void (*ln_cb)(const char *, const char *, linenoiseCompletions *);  /**< linenoise callback to call */
+        void (*yl_cb)(const char *, char ***, unsigned int *);              /**< yanglint callback to call */
+    } ac[] = {
+        {"add", NULL, 1, linenoisePathCompletion, NULL},
+        {"searchpath", NULL, 0, linenoisePathCompletion, NULL},
+        {"data", NULL, 0, linenoisePathCompletion, NULL},
+        {"print", NULL, 0, NULL, get_model_completion},
+        {"feature", NULL, 0, NULL, get_model_completion},
+        {"print", "-P", 1, NULL, get_schema_completion},
+    };
+    size_t cmd_len;
+    const char *last;
+    char **matches = NULL;
+    unsigned int match_count = 0, i;
+
+    if (buf == hint) {
+        /* command autocomplete */
+        get_cmd_completion(hint, &matches, &match_count);
+
+    } else {
+        for (i = 0; i < (sizeof ac / sizeof *ac); ++i) {
+            cmd_len = strlen(ac[i].cmd);
+            if (strncmp(buf, ac[i].cmd, cmd_len) || (buf[cmd_len] != ' ')) {
+                /* not this command */
+                continue;
+            }
+
+            last = get_last_str(buf, hint);
+            if (ac[i].opt && strncmp(ac[i].opt, last, strlen(ac[i].opt))) {
+                /* autocompletion for (another) option */
+                continue;
+            }
+            if (!ac[i].last_opt && (last[0] == '-')) {
+                /* autocompletion for the command, not an option */
+                continue;
+            }
+            if ((last != buf) && (last[0] != '-')) {
+                /* autocompleted */
+                return;
+            }
+
+            /* callback */
+            if (ac[i].ln_cb) {
+                ac[i].ln_cb(buf, hint, lc);
+            } else {
+                ac[i].yl_cb(hint, &matches, &match_count);
+            }
+            break;
+        }
+    }
+
+    /* transform matches into autocompletion, if needed */
+    for (i = 0; i < match_count; ++i) {
+        linenoiseAddCompletion(lc, matches[i]);
+        free(matches[i]);
+    }
+    free(matches);
+}
diff --git a/tools/lint/completion.h b/tools/lint/completion.h
new file mode 100644
index 0000000..20b8d17
--- /dev/null
+++ b/tools/lint/completion.h
@@ -0,0 +1,25 @@
+/**
+ * @file completion.h
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @brief libyang's yanglint tool auto completion header
+ *
+ * Copyright (c) 2015 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#ifndef COMPLETION_H_
+#define COMPLETION_H_
+
+#include "./linenoise/linenoise.h"
+
+/**
+ * @brief Command line completion callback.
+ */
+void complete_cmd(const char *buf, const char *hint, linenoiseCompletions *lc);
+
+#endif /* COMPLETION_H_ */
diff --git a/tools/lint/configuration.c b/tools/lint/configuration.c
new file mode 100644
index 0000000..86179fa
--- /dev/null
+++ b/tools/lint/configuration.c
@@ -0,0 +1,125 @@
+/**
+ * @file configuration.c
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @brief yanglint configuration
+ *
+ * Copyright (c) 2017 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#include "configuration.h"
+
+#include <errno.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "linenoise/linenoise.h"
+
+#include "common.h"
+
+/* Yanglint home (appended to ~/) */
+#define YL_DIR ".yanglint"
+
+char *
+get_yanglint_dir(void)
+{
+    int ret;
+    struct passwd *pw;
+    char *user_home, *yl_dir;
+
+    if (!(pw = getpwuid(getuid()))) {
+        YLMSG_E("Determining home directory failed (%s).\n", strerror(errno));
+        return NULL;
+    }
+    user_home = pw->pw_dir;
+
+    yl_dir = malloc(strlen(user_home) + 1 + strlen(YL_DIR) + 1);
+    if (!yl_dir) {
+        YLMSG_E("Memory allocation failed (%s).\n", strerror(errno));
+        return NULL;
+    }
+    sprintf(yl_dir, "%s/%s", user_home, YL_DIR);
+
+    ret = access(yl_dir, R_OK | X_OK);
+    if (ret == -1) {
+        if (errno == ENOENT) {
+            /* directory does not exist */
+            YLMSG_W("Configuration directory \"%s\" does not exist, creating it.\n", yl_dir);
+            if (mkdir(yl_dir, 00700)) {
+                if (errno != EEXIST) {
+                    /* parallel execution, yay */
+                    YLMSG_E("Configuration directory \"%s\" cannot be created (%s).\n", yl_dir, strerror(errno));
+                    free(yl_dir);
+                    return NULL;
+                }
+            }
+        } else {
+            YLMSG_E("Configuration directory \"%s\" exists but cannot be accessed (%s).\n", yl_dir, strerror(errno));
+            free(yl_dir);
+            return NULL;
+        }
+    }
+
+    return yl_dir;
+}
+
+void
+load_config(void)
+{
+    char *yl_dir, *history_file;
+
+    if ((yl_dir = get_yanglint_dir()) == NULL) {
+        return;
+    }
+
+    history_file = malloc(strlen(yl_dir) + 9);
+    if (!history_file) {
+        YLMSG_E("Memory allocation failed (%s).\n", strerror(errno));
+        free(yl_dir);
+        return;
+    }
+
+    sprintf(history_file, "%s/history", yl_dir);
+    if (access(history_file, F_OK) && (errno == ENOENT)) {
+        YLMSG_W("No saved history.\n");
+    } else if (linenoiseHistoryLoad(history_file)) {
+        YLMSG_E("Failed to load history.\n");
+    }
+
+    free(history_file);
+    free(yl_dir);
+}
+
+void
+store_config(void)
+{
+    char *yl_dir, *history_file;
+
+    if ((yl_dir = get_yanglint_dir()) == NULL) {
+        return;
+    }
+
+    history_file = malloc(strlen(yl_dir) + 9);
+    if (!history_file) {
+        YLMSG_E("Memory allocation failed (%s).\n", strerror(errno));
+        free(yl_dir);
+        return;
+    }
+
+    sprintf(history_file, "%s/history", yl_dir);
+    if (linenoiseHistorySave(history_file)) {
+        YLMSG_E("Failed to save history.\n");
+    }
+
+    free(history_file);
+    free(yl_dir);
+}
diff --git a/tools/lint/configuration.h b/tools/lint/configuration.h
new file mode 100644
index 0000000..d677876
--- /dev/null
+++ b/tools/lint/configuration.h
@@ -0,0 +1,36 @@
+/**
+ * @file configuration.h
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @brief yanglint configuration header
+ *
+ * Copyright (c) 2017 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#ifndef CONFIGURATION_H_
+#define CONFIGURATION_H_
+
+/**
+ * @brief Finds the current user's yanglint dir
+ * @return NULL on failure, dynamically allocated yanglint dir path
+ * otherwise
+ */
+char *get_yanglint_dir(void);
+
+/**
+ * @brief Checks all the relevant files and directories creating any
+ * that are missing, sets the saved configuration (currently only history)
+ */
+void load_config(void);
+
+/**
+ * @brief Saves the current configuration (currently only history)
+ */
+void store_config(void);
+
+#endif /* CONFIGURATION_H_ */
diff --git a/tools/lint/examples/README.md b/tools/lint/examples/README.md
new file mode 100644
index 0000000..604591c
--- /dev/null
+++ b/tools/lint/examples/README.md
@@ -0,0 +1,471 @@
+# YANGLINT - Interactive Mode Examples
+
+This text provides several use-case of the `yanglint(1)` interactive
+mode. For basic information about the `yanglint(1)` usage, please see
+the man page.
+
+The examples are supposed to be went through one by one. Some of the examples
+suppose the specific schemas loaded in some of the previous example is still
+loaded. If an addition work is need, the *preparation* part in the example
+provides information what to do.
+
+To show all available command of the `yanglint(1)`, use the `help` command:
+```
+> help
+Available commands:
+  help            Display commands description
+  add             Add a new module from a specific file
+  load            Load a new schema from the searchdirs
+  print           Print a module
+  data            Load, validate and optionally print instance data
+  list            List all the loaded modules
+  feature         Print all features of module(s) with their state
+  searchpath      Print/set the search path(s) for schemas
+  clear           Clear the context - remove all the loaded modules
+  verb            Change verbosity
+  debug           Display specific debug message groups
+  quit            Quit the program
+  ?               Display commands description
+  exit            Quit the program
+```
+To show the information about the specific command, use the `help` command in
+combination with the command name you are interested in:
+```
+> help searchpath
+Usage: searchpath [--clear] [<modules-dir-path> ...]
+                  Set paths of directories where to search for imports and
+                  includes of the schema modules. The current working directory
+                  and the path of the module being added is used implicitly.
+                  The 'load' command uses these paths to search even for the
+                  schema modules to be loaded.
+```
+
+The input files referred in this document are available together with this
+document.
+
+## Duplicit Data Model
+
+Let's have two data models [module1.yang](./module1.yang)
+and [module1b.yang](./module1b.yang).
+They differ in the module name but their namespaces are the same.
+
+Preparation:
+
+```
+> clear
+> add module1.yang
+> list
+```
+
+Output:
+
+```
+List of the loaded models:
+    i ietf-yang-metadata@2016-08-05
+    I yang@2022-06-16
+    i ietf-inet-types@2013-07-15
+    i ietf-yang-types@2013-07-15
+    I ietf-yang-schema-mount@2019-01-14
+    I module1
+```
+
+Command and its output:
+
+```
+> add module1b.yang
+libyang[0]: Two different modules ("module1" and "module1b") have the same namespace "urn:yanglint:module".
+libyang[0]: Parsing module "module1b" failed.
+```
+
+## Yang Data Model Validation
+
+**YANG/YIN syntax**
+
+`module2.yin` contains a syntax error.
+There is a bad syntax of the `type` statement in YIN file.
+
+```
+<type value="string"/>
+```
+
+instead of
+
+```
+<type name="string"/>
+```
+
+Preparation:
+
+```
+> clear
+```
+
+Command and its output:
+
+```
+> add module2.yin
+libyang[0]: Unexpected attribute "value" of "type" element. (path: Line number 8.)
+libyang[0]: Parsing module "module2" failed.
+```
+
+Similarly, there is a typo in `module2.yang`.
+
+**XPath errors**
+
+`libyang` and `yanglint(1)` is able to detect also errors in XPath expressions.
+In `module3.yang` the `must` expression refers to the node which does not exists.
+
+Preparation:
+
+```
+> clear
+```
+
+Command and its output:
+
+```
+> add module3.yang
+libyang[1]: Schema node "a" for parent "/module3:c" not found; in expr "../c/a" with context node "/module3:m".
+```
+
+Note that libyang prints only a warning in this case because it is not
+specified that XPath expressions must refer to existing nodes.
+
+## Data Validation
+
+Preparation:
+
+```
+> clear
+> add ietf-netconf-acm.yang
+```
+
+**Unknown data**
+
+By default, yanglint ignores unknown data and no error is printed (you can
+compare real content of the `datastore.xml` file and what yanglint prints
+in the following command if you add `-f xml` option).
+
+Command and its output:
+
+```
+> data -t config datastore.xml
+```
+
+We use option `-t` to specify type of the data in `datastore.xml`. By the
+`config` value we declare that the input file contains all the configuration
+data (with at least all the mandatory nodes as required by the loaded schemas),
+but without the status data. More examples of different data types will follow.
+
+Command and its output:
+
+```
+> data -t config datastore.xml
+libyang[0]: No module with namespace "urn:ietf:params:xml:ns:yang:ietf-interfaces" in the context. (path: Line number 20.)
+YANGLINT[E]: Failed to parse input data file "datastore.xml".
+```
+
+Note that in case of working with complete datastore including the status data
+(no `-t` option is specified), `yanglint(1)` has to add status data from its
+internal `ietf-yang-library` module.
+
+**RPC and RPC-reply**
+
+It is possible to validate RPCs and their replies as well.
+
+Peparation:
+
+```
+> clear
+> add module4.yang
+```
+
+Command and its output:
+
+```
+> data -t rpc rpc.xml
+```
+
+Reply to this RPC can be validated too, but it must be nested in the original
+RPC element.
+
+Command and its output:
+
+```
+> data -t reply ../tools/lint/examples/rpc-reply.xml
+```
+
+**action and action-reply**
+
+Actions are validated the same way as RPCs except you need to be careful
+about the input file structure. No NETCONF-specific envelopes are expected.
+
+Preparation
+
+```
+> clear
+> add module4.yang
+```
+
+Command and its output:
+
+```
+> data -t rpc action.xml
+```
+
+Command and its output:
+
+```
+> data -t rpc action-reply.xml action.xml
+```
+
+**notification**
+
+Both top-level and nested notification can be validated.
+
+Preparation
+
+```
+> clear
+> add module4.yang
+```
+
+Command and its output:
+
+```
+> data -t notif notification.xml
+```
+
+Command and its output:
+
+```
+> data -t notif nested-notification.xml
+```
+
+
+**Multiple top-level elements in a single document**
+
+As a feature and in conflict with the XML definition, `yanglint(1)` (and libyang)
+is able to read XML files with multiple top-level elements. Such documents
+are not well-formed according to the XML spec, but it fits to how the YANG
+interconnects data trees (defined as top-level elements of a single schema
+or by multiple schemas).
+
+Preparation:
+
+```
+> clear
+> add ietf-netconf-acm.yang
+> add ietf-interfaces.yang
+> add ietf-ip.yang
+> add iana-if-type.yang
+```
+
+Command and its output:
+
+```
+> data -t config datastore.xml
+```
+
+**Different data content types**
+
+Since NETCONF requires the data described by YANG to be used in different
+situations (e.g. as <edit-config data>, result of the <get> with status data
+included or as a result of the <get-config> without the status data and
+possibly filtered, so without specified subtrees), it must be possible to
+specify which kind of data is going to be parsed. In `yanglint(1)`, this is done
+via `-t` option. The list of supported modes can be displayed by the `-h`
+option given to the `data` command. In general, the `auto` value lets the
+`yanglint(1)` to recognize the data type automatically by the additional top-level
+elements added to the parsed data. This is the same way as `pyang(1)` uses. Note,
+that the automatic data type recognition is available only for the XML input.
+
+**Malformed XML data**
+
+Command and its output:
+
+```
+> data -t edit config-missing-key.xml
+libyang[0]: Node "nam" not found as a child of "group" node. (path: Schema location "/ietf-netconf-acm:nacm/groups/group", data location "/ietf-netconf-acm:group", line number 19.)
+YANGLINT[E]: Failed to parse input data file "config-missing-key.xml".
+```
+
+**State information in edit-config XML**
+
+Command and its output:
+
+```
+> data -t edit config-unknown-element.xml
+libyang[0]: Unexpected data state node "denied-operations" found. (path: Schema location "/ietf-netconf-acm:nacm/denied-operations", data location "/ietf-netconf-acm:nacm", line number 24.)
+YANGLINT[E]: Failed to parse input data file "config-unknown-element.xml".
+```
+
+**Missing required element in NETCONF data**
+
+Command and its output:
+
+```
+> data data-missing-key.xml
+libyang[0]: List instance is missing its key "name". (path: Schema location "/ietf-netconf-acm:nacm/rule-list/rule", data location "/ietf-netconf-acm:rule", line number 10.)
+YANGLINT[E]: Failed to parse input data file "data-missing-key.xml".
+```
+
+**Malformed XML**
+
+Command and its output:
+
+```
+> data data-malformed-xml.xml
+libyang[0]: Node "nam" not found as a child of "rule" node. (path: Schema location "/ietf-netconf-acm:nacm/rule-list/rule", data location "/ietf-netconf-acm:rule", line number 8.)
+YANGLINT[E]: Failed to parse input data file "data-malformed-xml.xml".
+```
+
+Command and its output:
+
+```
+> data data-malformed-xml2.xml
+libyang[0]: Child element "module-name" inside a terminal node "name" found. (path: Schema location "/ietf-netconf-acm:nacm/rule-list/rule/name", data location "/ietf-netconf-acm:name", line number 7.)
+YANGLINT[E]: Failed to parse input data file "data-malformed-xml2.xml".
+```
+
+**Bad value**
+
+Command and its output:
+
+```
+> data data-out-of-range-value.xml
+libyang[0]: Value "-1" is out of type uint32 min/max bounds. (path: Schema location "/ietf-netconf-acm:nacm/denied-operations", data location "/ietf-netconf-acm:nacm", line number 24.)
+YANGLINT[E]: Failed to parse input data file "data-out-of-range-value.xml".
+```
+
+## Validation of "when" Statement in Data
+
+Preparation:
+
+```
+> clear
+> add ietf-netconf-acm-when.yang
+```
+
+**`When` condition is not satisfied since `denied-operation = 0`**
+
+Command and its output:
+
+```
+> data data-acm.xml
+libyang[0]: When condition "../denied-operations > 0" not satisfied. (path: Schema location "/ietf-netconf-acm-when:nacm/denied-data-writes", data location "/ietf-netconf-acm-when:nacm/denied-data-writes".)
+YANGLINT[E]: Failed to parse input data file "data-acm.xml".
+```
+
+## Printing a Data Model
+
+Preparation:
+
+```
+> clear
+> add ietf-netconf-acm.yang
+```
+
+**Print a `pyang`-style tree**
+
+Command and its output:
+
+```
+> print ietf-netconf-acm
+module: ietf-netconf-acm
+  +--rw nacm
+     +--rw enable-nacm?              boolean
+     +--rw read-default?             action-type
+     +--rw write-default?            action-type
+     +--rw exec-default?             action-type
+     +--rw enable-external-groups?   boolean
+     +--ro denied-operations         yang:zero-based-counter32
+     +--ro denied-data-writes        yang:zero-based-counter32
+     +--ro denied-notifications      yang:zero-based-counter32
+     +--rw groups
+     |  +--rw group* [name]
+     |     +--rw name         group-name-type
+     |     +--rw user-name*   user-name-type
+     +--rw rule-list* [name]
+        +--rw name     string
+        +--rw group*   union
+        +--rw rule* [name]
+           +--rw name                 string
+           +--rw module-name?         union
+           +--rw (rule-type)?
+           |  +--:(protocol-operation)
+           |  |  +--rw rpc-name?   union
+           |  +--:(notification)
+           |  |  +--rw notification-name?   union
+           |  +--:(data-node)
+           |     +--rw path    node-instance-identifier
+           +--rw access-operations?   union
+           +--rw action               action-type
+           +--rw comment?             string
+```
+
+**Print information about specific model part**
+
+Command and its output:
+
+```
+> print -f info -P /ietf-netconf-acm:nacm/ietf-netconf-acm:enable-nacm ietf-netconf-acm
+leaf enable-nacm {
+  ietf-netconf-acm:default-deny-all;
+  type boolean;
+  default "true";
+  config true;
+  status current;
+  description
+    "Enables or disables all NETCONF access control
+     enforcement.  If 'true', then enforcement
+     is enabled.  If 'false', then enforcement
+     is disabled.";
+}
+```
+
+## Usage of `feature` in Yang
+
+Preparation:
+
+```
+> clear
+> add ietf-interfaces.yang
+> add ietf-ip.yang -F ietf-ip:*
+> add iana-if-type.yang
+```
+
+Note: This example also shows `JSON` output of the command.
+
+Command and its output:
+```
+> feature ietf-ip
+ietf-ip features:
+        ipv4-non-contiguous-netmasks (on)
+        ipv6-privacy-autoconf        (on)
+> data -f json -t config data-ip.xml
+{
+  "ietf-interfaces:interfaces": {
+    "interface": [
+      {
+        "name": "eth0",
+        "description": "Wire Connection",
+        "type": "iana-if-type:ethernetCsmacd",
+        "enabled": true,
+        "ietf-ip:ipv4": {
+          "address": [
+            {
+              "ip": "192.168.1.15",
+              "netmask": "255.255.255.0"
+            },
+            {
+              "ip": "192.168.1.10",
+              "netmask": "255.255.255.0"
+            }
+          ]
+        }
+      }
+    ]
+  }
+}
+```
diff --git a/tools/lint/examples/action-reply.xml b/tools/lint/examples/action-reply.xml
new file mode 100644
index 0000000..e6fc284
--- /dev/null
+++ b/tools/lint/examples/action-reply.xml
@@ -0,0 +1,8 @@
+<cont1 xmlns="urn:module4">
+  <list>
+    <leaf1>key_val</leaf1>
+    <act>
+      <leaf3>some_output</leaf3>
+    </act>
+  </list>
+</cont1>
diff --git a/tools/lint/examples/action.xml b/tools/lint/examples/action.xml
new file mode 100644
index 0000000..661fecf
--- /dev/null
+++ b/tools/lint/examples/action.xml
@@ -0,0 +1,8 @@
+<cont1 xmlns="urn:module4">
+  <list>
+    <leaf1>key_val</leaf1>
+    <act>
+      <leaf2>some_input</leaf2>
+    </act>
+  </list>
+</cont1>
diff --git a/tools/lint/examples/config-acm.xml b/tools/lint/examples/config-acm.xml
new file mode 100644
index 0000000..8c99419
--- /dev/null
+++ b/tools/lint/examples/config-acm.xml
@@ -0,0 +1,24 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm" xmlns:nc="urn:ietf:params:xml:ns:netconf:base:1.0">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <group nc:operation="create">test</group>
+    <rule>
+      <name>almighty</name>
+      <module-name>*</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>test</name>
+      <user-name>smith</user-name>
+    </group>
+    <group>
+      <name>almighty</name>
+      <user-name>smith</user-name>
+      <user-name>doe</user-name>
+    </group>
+  </groups>
+</nacm>
diff --git a/tools/lint/examples/config-missing-key.xml b/tools/lint/examples/config-missing-key.xml
new file mode 100644
index 0000000..c30c2b0
--- /dev/null
+++ b/tools/lint/examples/config-missing-key.xml
@@ -0,0 +1,24 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <group>test</group>
+    <rule>
+      <name>almighty</name>
+      <module-name>*</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>test</name>
+      <user-name>smith</user-name>
+    </group>
+    <group>
+      <nam>almighty</name>
+      <user-name>smith</user-name>
+      <user-name>doe</user-name>
+    </group>
+  </groups>
+</nacm>
diff --git a/tools/lint/examples/config-unknown-element.xml b/tools/lint/examples/config-unknown-element.xml
new file mode 100644
index 0000000..66ae880
--- /dev/null
+++ b/tools/lint/examples/config-unknown-element.xml
@@ -0,0 +1,27 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <group>test</group>
+    <rule>
+      <name>almighty</name>
+      <module-name>*</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>test</name>
+      <user-name>smith</user-name>
+    </group>
+    <group>
+      <name>almighty</name>
+      <user-name>smith</user-name>
+      <user-name>doe</user-name>
+    </group>
+  </groups>
+  <denied-operations>0</denied-operations>
+  <denied-data-writes>0</denied-data-writes>
+  <denied-notifications>0</denied-notifications>
+</nacm>
diff --git a/tools/lint/examples/data-acm.xml b/tools/lint/examples/data-acm.xml
new file mode 100644
index 0000000..66ae880
--- /dev/null
+++ b/tools/lint/examples/data-acm.xml
@@ -0,0 +1,27 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <group>test</group>
+    <rule>
+      <name>almighty</name>
+      <module-name>*</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>test</name>
+      <user-name>smith</user-name>
+    </group>
+    <group>
+      <name>almighty</name>
+      <user-name>smith</user-name>
+      <user-name>doe</user-name>
+    </group>
+  </groups>
+  <denied-operations>0</denied-operations>
+  <denied-data-writes>0</denied-data-writes>
+  <denied-notifications>0</denied-notifications>
+</nacm>
diff --git a/tools/lint/examples/data-ip.xml b/tools/lint/examples/data-ip.xml
new file mode 100644
index 0000000..1894f6d
--- /dev/null
+++ b/tools/lint/examples/data-ip.xml
@@ -0,0 +1,12 @@
+<interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
+  <interface>
+    <name>eth0</name>
+    <description>Wire Connection</description>
+    <type xmlns:ift="urn:ietf:params:xml:ns:yang:iana-if-type">ift:ethernetCsmacd</type>
+    <enabled>true</enabled>
+    <ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
+      <address><ip>192.168.1.15</ip><netmask>255.255.255.0</netmask></address>
+      <address><ip>192.168.1.10</ip><netmask>255.255.255.0</netmask></address>
+    </ipv4>
+  </interface>
+</interfaces>
diff --git a/tools/lint/examples/data-malformed-xml.xml b/tools/lint/examples/data-malformed-xml.xml
new file mode 100644
index 0000000..908d79b
--- /dev/null
+++ b/tools/lint/examples/data-malformed-xml.xml
@@ -0,0 +1,27 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <group>test</group>
+    <rule>
+      <nam>almighty
+      <module-name>*</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>test</name>
+      <user-name>smith</user-name>
+    </group>
+    <group>
+      <name>almighty</name>
+      <user-name>smith</user-name>
+      <user-name>doe</user-name>
+    </group>
+  </groups>
+  <denied-operations>0</denied-operations>
+  <denied-data-writes>0</denied-data-writes>
+  <denied-notifications>0</denied-notifications>
+</nacm>
diff --git a/tools/lint/examples/data-malformed-xml2.xml b/tools/lint/examples/data-malformed-xml2.xml
new file mode 100644
index 0000000..8d0e5f4
--- /dev/null
+++ b/tools/lint/examples/data-malformed-xml2.xml
@@ -0,0 +1,26 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <group>test</group>
+    <rule>
+      <name>almighty<module-name></name> *</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>test</name>
+      <user-name>smith</user-name>
+    </group>
+    <group>
+      <name>almighty</name>
+      <user-name>smith</user-name>
+      <user-name>doe</user-name>
+    </group>
+  </groups>
+  <denied-operations>0</denied-operations>
+  <denied-data-writes>0</denied-data-writes>
+  <denied-notifications>0</denied-notifications>
+</nacm>
diff --git a/tools/lint/examples/data-missing-key.xml b/tools/lint/examples/data-missing-key.xml
new file mode 100644
index 0000000..2e9684d
--- /dev/null
+++ b/tools/lint/examples/data-missing-key.xml
@@ -0,0 +1,26 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <group>test</group>
+    <rule>
+      <module-name>*</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>test</name>
+      <user-name>smith</user-name>
+    </group>
+    <group>
+      <name>almighty</name>
+      <user-name>smith</user-name>
+      <user-name>doe</user-name>
+    </group>
+  </groups>
+  <denied-operations>0</denied-operations>
+  <denied-data-writes>0</denied-data-writes>
+  <denied-notifications>0</denied-notifications>
+</nacm>
diff --git a/tools/lint/examples/data-out-of-range-value.xml b/tools/lint/examples/data-out-of-range-value.xml
new file mode 100644
index 0000000..2af5ba9
--- /dev/null
+++ b/tools/lint/examples/data-out-of-range-value.xml
@@ -0,0 +1,27 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <group>test</group>
+    <rule>
+      <name>almighty</name>
+      <module-name>*</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>test</name>
+      <user-name>smith</user-name>
+    </group>
+    <group>
+      <name>almighty</name>
+      <user-name>smith</user-name>
+      <user-name>doe</user-name>
+    </group>
+  </groups>
+  <denied-operations>-1</denied-operations>
+  <denied-data-writes>0</denied-data-writes>
+  <denied-notifications>0</denied-notifications>
+</nacm>
diff --git a/tools/lint/examples/datastore.xml b/tools/lint/examples/datastore.xml
new file mode 100644
index 0000000..c6a6fc9
--- /dev/null
+++ b/tools/lint/examples/datastore.xml
@@ -0,0 +1,29 @@
+<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
+  <rule-list>
+    <name>almighty</name>
+    <group>almighty</group>
+    <rule>
+      <name>almighty</name>
+      <module-name>*</module-name>
+      <access-operations>*</access-operations>
+      <action>permit</action>
+    </rule>
+  </rule-list>
+  <groups>
+    <group>
+      <name>almighty</name>
+      <user-name>smith</user-name>
+    </group>
+  </groups>
+</nacm>
+<interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
+  <interface>
+    <name>eth0</name>
+    <description>Wire Connection</description>
+    <type xmlns:ift="urn:ietf:params:xml:ns:yang:iana-if-type">ift:ethernetCsmacd</type>
+    <enabled>true</enabled>
+    <ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
+      <address><ip>192.168.1.15</ip><prefix-length>24</prefix-length></address>
+    </ipv4>
+  </interface>
+</interfaces>
diff --git a/tools/lint/examples/iana-if-type.yang b/tools/lint/examples/iana-if-type.yang
new file mode 100644
index 0000000..5dd8219
--- /dev/null
+++ b/tools/lint/examples/iana-if-type.yang
@@ -0,0 +1,1547 @@
+module iana-if-type {
+  namespace "urn:ietf:params:xml:ns:yang:iana-if-type";
+  prefix ianaift;
+
+  import ietf-interfaces {
+    prefix if;
+  }
+
+  organization "IANA";
+  contact
+    "        Internet Assigned Numbers Authority
+
+     Postal: ICANN
+             4676 Admiralty Way, Suite 330
+             Marina del Rey, CA 90292
+
+     Tel:    +1 310 823 9358
+     <mailto:iana@iana.org>";
+  description
+    "This YANG module defines YANG identities for IANA-registered
+     interface types.
+
+     This YANG module is maintained by IANA and reflects the
+     'ifType definitions' registry.
+
+     The latest revision of this YANG module can be obtained from
+     the IANA web site.
+
+     Requests for new values should be made to IANA via
+     email (iana@iana.org).
+
+     Copyright (c) 2014 IETF Trust and the persons identified as
+     authors of the code.  All rights reserved.
+
+     Redistribution and use in source and binary forms, with or
+     without modification, is permitted pursuant to, and subject
+     to the license terms contained in, the Simplified BSD License
+     set forth in Section 4.c of the IETF Trust's Legal Provisions
+     Relating to IETF Documents
+     (http://trustee.ietf.org/license-info).
+
+     The initial version of this YANG module is part of RFC 7224;
+     see the RFC itself for full legal notices.";
+    reference
+      "IANA 'ifType definitions' registry.
+       <http://www.iana.org/assignments/smi-numbers>";
+
+  revision 2014-05-08 {
+    description
+      "Initial revision.";
+    reference
+      "RFC 7224: IANA Interface Type YANG Module";
+  }
+
+  identity iana-interface-type {
+    base if:interface-type;
+    description
+      "This identity is used as a base for all interface types
+       defined in the 'ifType definitions' registry.";
+  }
+
+
+
+
+
+
+  identity other {
+    base iana-interface-type;
+  }
+  identity regular1822 {
+    base iana-interface-type;
+  }
+  identity hdh1822 {
+    base iana-interface-type;
+  }
+  identity ddnX25 {
+    base iana-interface-type;
+  }
+  identity rfc877x25 {
+    base iana-interface-type;
+    reference
+      "RFC 1382 - SNMP MIB Extension for the X.25 Packet Layer";
+  }
+  identity ethernetCsmacd {
+    base iana-interface-type;
+    description
+      "For all Ethernet-like interfaces, regardless of speed,
+       as per RFC 3635.";
+    reference
+      "RFC 3635 - Definitions of Managed Objects for the
+                  Ethernet-like Interface Types";
+  }
+  identity iso88023Csmacd {
+    base iana-interface-type;
+    status deprecated;
+    description
+      "Deprecated via RFC 3635.
+       Use ethernetCsmacd(6) instead.";
+    reference
+      "RFC 3635 - Definitions of Managed Objects for the
+                  Ethernet-like Interface Types";
+  }
+  identity iso88024TokenBus {
+    base iana-interface-type;
+  }
+  identity iso88025TokenRing {
+    base iana-interface-type;
+  }
+  identity iso88026Man {
+    base iana-interface-type;
+  }
+  identity starLan {
+    base iana-interface-type;
+    status deprecated;
+    description
+      "Deprecated via RFC 3635.
+       Use ethernetCsmacd(6) instead.";
+    reference
+      "RFC 3635 - Definitions of Managed Objects for the
+                  Ethernet-like Interface Types";
+  }
+  identity proteon10Mbit {
+    base iana-interface-type;
+  }
+  identity proteon80Mbit {
+    base iana-interface-type;
+  }
+  identity hyperchannel {
+    base iana-interface-type;
+  }
+  identity fddi {
+    base iana-interface-type;
+    reference
+      "RFC 1512 - FDDI Management Information Base";
+  }
+  identity lapb {
+    base iana-interface-type;
+    reference
+      "RFC 1381 - SNMP MIB Extension for X.25 LAPB";
+  }
+  identity sdlc {
+    base iana-interface-type;
+  }
+  identity ds1 {
+    base iana-interface-type;
+    description
+      "DS1-MIB.";
+    reference
+      "RFC 4805 - Definitions of Managed Objects for the
+                  DS1, J1, E1, DS2, and E2 Interface Types";
+  }
+  identity e1 {
+    base iana-interface-type;
+    status obsolete;
+    description
+      "Obsolete; see DS1-MIB.";
+    reference
+      "RFC 4805 - Definitions of Managed Objects for the
+                  DS1, J1, E1, DS2, and E2 Interface Types";
+  }
+
+
+  identity basicISDN {
+    base iana-interface-type;
+    description
+      "No longer used.  See also RFC 2127.";
+  }
+  identity primaryISDN {
+    base iana-interface-type;
+    description
+      "No longer used.  See also RFC 2127.";
+  }
+  identity propPointToPointSerial {
+    base iana-interface-type;
+    description
+      "Proprietary serial.";
+  }
+  identity ppp {
+    base iana-interface-type;
+  }
+  identity softwareLoopback {
+    base iana-interface-type;
+  }
+  identity eon {
+    base iana-interface-type;
+    description
+      "CLNP over IP.";
+  }
+  identity ethernet3Mbit {
+    base iana-interface-type;
+  }
+  identity nsip {
+    base iana-interface-type;
+    description
+      "XNS over IP.";
+  }
+  identity slip {
+    base iana-interface-type;
+    description
+      "Generic SLIP.";
+  }
+  identity ultra {
+    base iana-interface-type;
+    description
+      "Ultra Technologies.";
+  }
+  identity ds3 {
+    base iana-interface-type;
+    description
+      "DS3-MIB.";
+    reference
+      "RFC 3896 - Definitions of Managed Objects for the
+                  DS3/E3 Interface Type";
+  }
+  identity sip {
+    base iana-interface-type;
+    description
+      "SMDS, coffee.";
+    reference
+      "RFC 1694 - Definitions of Managed Objects for SMDS
+                  Interfaces using SMIv2";
+  }
+  identity frameRelay {
+    base iana-interface-type;
+    description
+      "DTE only.";
+    reference
+      "RFC 2115 - Management Information Base for Frame Relay
+                  DTEs Using SMIv2";
+  }
+  identity rs232 {
+    base iana-interface-type;
+    reference
+      "RFC 1659 - Definitions of Managed Objects for RS-232-like
+                  Hardware Devices using SMIv2";
+  }
+  identity para {
+    base iana-interface-type;
+    description
+      "Parallel-port.";
+    reference
+      "RFC 1660 - Definitions of Managed Objects for
+                  Parallel-printer-like Hardware Devices using
+                  SMIv2";
+  }
+  identity arcnet {
+    base iana-interface-type;
+    description
+      "ARCnet.";
+  }
+  identity arcnetPlus {
+    base iana-interface-type;
+    description
+      "ARCnet Plus.";
+  }
+
+
+
+  identity atm {
+    base iana-interface-type;
+    description
+      "ATM cells.";
+  }
+  identity miox25 {
+    base iana-interface-type;
+    reference
+      "RFC 1461 - SNMP MIB extension for Multiprotocol
+                  Interconnect over X.25";
+  }
+  identity sonet {
+    base iana-interface-type;
+    description
+      "SONET or SDH.";
+  }
+  identity x25ple {
+    base iana-interface-type;
+    reference
+      "RFC 2127 - ISDN Management Information Base using SMIv2";
+  }
+  identity iso88022llc {
+    base iana-interface-type;
+  }
+  identity localTalk {
+    base iana-interface-type;
+  }
+  identity smdsDxi {
+    base iana-interface-type;
+  }
+  identity frameRelayService {
+    base iana-interface-type;
+    description
+      "FRNETSERV-MIB.";
+    reference
+      "RFC 2954 - Definitions of Managed Objects for Frame
+                  Relay Service";
+  }
+  identity v35 {
+    base iana-interface-type;
+  }
+  identity hssi {
+    base iana-interface-type;
+  }
+  identity hippi {
+    base iana-interface-type;
+  }
+
+  identity modem {
+    base iana-interface-type;
+    description
+      "Generic modem.";
+  }
+  identity aal5 {
+    base iana-interface-type;
+    description
+      "AAL5 over ATM.";
+  }
+  identity sonetPath {
+    base iana-interface-type;
+  }
+  identity sonetVT {
+    base iana-interface-type;
+  }
+  identity smdsIcip {
+    base iana-interface-type;
+    description
+      "SMDS InterCarrier Interface.";
+  }
+  identity propVirtual {
+    base iana-interface-type;
+    description
+      "Proprietary virtual/internal.";
+    reference
+      "RFC 2863 - The Interfaces Group MIB";
+  }
+  identity propMultiplexor {
+    base iana-interface-type;
+    description
+      "Proprietary multiplexing.";
+    reference
+      "RFC 2863 - The Interfaces Group MIB";
+  }
+  identity ieee80212 {
+    base iana-interface-type;
+    description
+      "100BaseVG.";
+  }
+  identity fibreChannel {
+    base iana-interface-type;
+    description
+      "Fibre Channel.";
+  }
+
+
+
+  identity hippiInterface {
+    base iana-interface-type;
+    description
+      "HIPPI interfaces.";
+  }
+  identity frameRelayInterconnect {
+    base iana-interface-type;
+    status obsolete;
+    description
+      "Obsolete; use either
+       frameRelay(32) or frameRelayService(44).";
+  }
+  identity aflane8023 {
+    base iana-interface-type;
+    description
+      "ATM Emulated LAN for 802.3.";
+  }
+  identity aflane8025 {
+    base iana-interface-type;
+    description
+      "ATM Emulated LAN for 802.5.";
+  }
+  identity cctEmul {
+    base iana-interface-type;
+    description
+      "ATM Emulated circuit.";
+  }
+  identity fastEther {
+    base iana-interface-type;
+    status deprecated;
+    description
+      "Obsoleted via RFC 3635.
+       ethernetCsmacd(6) should be used instead.";
+    reference
+      "RFC 3635 - Definitions of Managed Objects for the
+                  Ethernet-like Interface Types";
+  }
+  identity isdn {
+    base iana-interface-type;
+    description
+      "ISDN and X.25.";
+    reference
+      "RFC 1356 - Multiprotocol Interconnect on X.25 and ISDN
+                  in the Packet Mode";
+  }
+
+
+
+  identity v11 {
+    base iana-interface-type;
+    description
+      "CCITT V.11/X.21.";
+  }
+  identity v36 {
+    base iana-interface-type;
+    description
+      "CCITT V.36.";
+  }
+  identity g703at64k {
+    base iana-interface-type;
+    description
+      "CCITT G703 at 64Kbps.";
+  }
+  identity g703at2mb {
+    base iana-interface-type;
+    status obsolete;
+    description
+      "Obsolete; see DS1-MIB.";
+  }
+  identity qllc {
+    base iana-interface-type;
+    description
+      "SNA QLLC.";
+  }
+  identity fastEtherFX {
+    base iana-interface-type;
+    status deprecated;
+    description
+      "Obsoleted via RFC 3635.
+       ethernetCsmacd(6) should be used instead.";
+    reference
+      "RFC 3635 - Definitions of Managed Objects for the
+                  Ethernet-like Interface Types";
+  }
+  identity channel {
+    base iana-interface-type;
+    description
+      "Channel.";
+  }
+  identity ieee80211 {
+    base iana-interface-type;
+    description
+      "Radio spread spectrum.";
+  }
+  identity ibm370parChan {
+    base iana-interface-type;
+    description
+      "IBM System 360/370 OEMI Channel.";
+  }
+  identity escon {
+    base iana-interface-type;
+    description
+      "IBM Enterprise Systems Connection.";
+  }
+  identity dlsw {
+    base iana-interface-type;
+    description
+      "Data Link Switching.";
+  }
+  identity isdns {
+    base iana-interface-type;
+    description
+      "ISDN S/T interface.";
+  }
+  identity isdnu {
+    base iana-interface-type;
+    description
+      "ISDN U interface.";
+  }
+  identity lapd {
+    base iana-interface-type;
+    description
+      "Link Access Protocol D.";
+  }
+  identity ipSwitch {
+    base iana-interface-type;
+    description
+      "IP Switching Objects.";
+  }
+  identity rsrb {
+    base iana-interface-type;
+    description
+      "Remote Source Route Bridging.";
+  }
+  identity atmLogical {
+    base iana-interface-type;
+    description
+      "ATM Logical Port.";
+    reference
+      "RFC 3606 - Definitions of Supplemental Managed Objects
+                  for ATM Interface";
+  }
+  identity ds0 {
+    base iana-interface-type;
+    description
+      "Digital Signal Level 0.";
+    reference
+      "RFC 2494 - Definitions of Managed Objects for the DS0
+                  and DS0 Bundle Interface Type";
+  }
+  identity ds0Bundle {
+    base iana-interface-type;
+    description
+      "Group of ds0s on the same ds1.";
+    reference
+      "RFC 2494 - Definitions of Managed Objects for the DS0
+                  and DS0 Bundle Interface Type";
+  }
+  identity bsc {
+    base iana-interface-type;
+    description
+      "Bisynchronous Protocol.";
+  }
+  identity async {
+    base iana-interface-type;
+    description
+      "Asynchronous Protocol.";
+  }
+  identity cnr {
+    base iana-interface-type;
+    description
+      "Combat Net Radio.";
+  }
+  identity iso88025Dtr {
+    base iana-interface-type;
+    description
+      "ISO 802.5r DTR.";
+  }
+  identity eplrs {
+    base iana-interface-type;
+    description
+      "Ext Pos Loc Report Sys.";
+  }
+  identity arap {
+    base iana-interface-type;
+    description
+      "Appletalk Remote Access Protocol.";
+  }
+  identity propCnls {
+    base iana-interface-type;
+    description
+      "Proprietary Connectionless Protocol.";
+  }
+  identity hostPad {
+    base iana-interface-type;
+    description
+      "CCITT-ITU X.29 PAD Protocol.";
+  }
+  identity termPad {
+    base iana-interface-type;
+    description
+      "CCITT-ITU X.3 PAD Facility.";
+  }
+  identity frameRelayMPI {
+    base iana-interface-type;
+    description
+      "Multiproto Interconnect over FR.";
+  }
+  identity x213 {
+    base iana-interface-type;
+    description
+      "CCITT-ITU X213.";
+  }
+  identity adsl {
+    base iana-interface-type;
+    description
+      "Asymmetric Digital Subscriber Loop.";
+  }
+  identity radsl {
+    base iana-interface-type;
+    description
+      "Rate-Adapt. Digital Subscriber Loop.";
+  }
+  identity sdsl {
+    base iana-interface-type;
+    description
+      "Symmetric Digital Subscriber Loop.";
+  }
+  identity vdsl {
+    base iana-interface-type;
+    description
+      "Very H-Speed Digital Subscrib. Loop.";
+  }
+  identity iso88025CRFPInt {
+    base iana-interface-type;
+    description
+      "ISO 802.5 CRFP.";
+  }
+  identity myrinet {
+    base iana-interface-type;
+    description
+      "Myricom Myrinet.";
+  }
+  identity voiceEM {
+    base iana-interface-type;
+    description
+      "Voice recEive and transMit.";
+  }
+  identity voiceFXO {
+    base iana-interface-type;
+    description
+      "Voice Foreign Exchange Office.";
+  }
+  identity voiceFXS {
+    base iana-interface-type;
+    description
+      "Voice Foreign Exchange Station.";
+  }
+  identity voiceEncap {
+    base iana-interface-type;
+    description
+      "Voice encapsulation.";
+  }
+  identity voiceOverIp {
+    base iana-interface-type;
+    description
+      "Voice over IP encapsulation.";
+  }
+  identity atmDxi {
+    base iana-interface-type;
+    description
+      "ATM DXI.";
+  }
+  identity atmFuni {
+    base iana-interface-type;
+    description
+      "ATM FUNI.";
+  }
+  identity atmIma {
+    base iana-interface-type;
+    description
+      "ATM IMA.";
+  }
+  identity pppMultilinkBundle {
+    base iana-interface-type;
+    description
+      "PPP Multilink Bundle.";
+  }
+  identity ipOverCdlc {
+    base iana-interface-type;
+    description
+      "IBM ipOverCdlc.";
+  }
+  identity ipOverClaw {
+    base iana-interface-type;
+    description
+      "IBM Common Link Access to Workstn.";
+  }
+  identity stackToStack {
+    base iana-interface-type;
+    description
+      "IBM stackToStack.";
+  }
+  identity virtualIpAddress {
+    base iana-interface-type;
+    description
+      "IBM VIPA.";
+  }
+  identity mpc {
+    base iana-interface-type;
+    description
+      "IBM multi-protocol channel support.";
+  }
+  identity ipOverAtm {
+    base iana-interface-type;
+    description
+      "IBM ipOverAtm.";
+    reference
+      "RFC 2320 - Definitions of Managed Objects for Classical IP
+                  and ARP Over ATM Using SMIv2 (IPOA-MIB)";
+  }
+  identity iso88025Fiber {
+    base iana-interface-type;
+    description
+      "ISO 802.5j Fiber Token Ring.";
+  }
+  identity tdlc {
+    base iana-interface-type;
+    description
+      "IBM twinaxial data link control.";
+  }
+  identity gigabitEthernet {
+    base iana-interface-type;
+    status deprecated;
+
+
+    description
+      "Obsoleted via RFC 3635.
+       ethernetCsmacd(6) should be used instead.";
+    reference
+      "RFC 3635 - Definitions of Managed Objects for the
+                  Ethernet-like Interface Types";
+  }
+  identity hdlc {
+    base iana-interface-type;
+    description
+      "HDLC.";
+  }
+  identity lapf {
+    base iana-interface-type;
+    description
+      "LAP F.";
+  }
+  identity v37 {
+    base iana-interface-type;
+    description
+      "V.37.";
+  }
+  identity x25mlp {
+    base iana-interface-type;
+    description
+      "Multi-Link Protocol.";
+  }
+  identity x25huntGroup {
+    base iana-interface-type;
+    description
+      "X25 Hunt Group.";
+  }
+  identity transpHdlc {
+    base iana-interface-type;
+    description
+      "Transp HDLC.";
+  }
+  identity interleave {
+    base iana-interface-type;
+    description
+      "Interleave channel.";
+  }
+  identity fast {
+    base iana-interface-type;
+    description
+      "Fast channel.";
+  }
+
+  identity ip {
+    base iana-interface-type;
+    description
+      "IP (for APPN HPR in IP networks).";
+  }
+  identity docsCableMaclayer {
+    base iana-interface-type;
+    description
+      "CATV Mac Layer.";
+  }
+  identity docsCableDownstream {
+    base iana-interface-type;
+    description
+      "CATV Downstream interface.";
+  }
+  identity docsCableUpstream {
+    base iana-interface-type;
+    description
+      "CATV Upstream interface.";
+  }
+  identity a12MppSwitch {
+    base iana-interface-type;
+    description
+      "Avalon Parallel Processor.";
+  }
+  identity tunnel {
+    base iana-interface-type;
+    description
+      "Encapsulation interface.";
+  }
+  identity coffee {
+    base iana-interface-type;
+    description
+      "Coffee pot.";
+    reference
+      "RFC 2325 - Coffee MIB";
+  }
+  identity ces {
+    base iana-interface-type;
+    description
+      "Circuit Emulation Service.";
+  }
+  identity atmSubInterface {
+    base iana-interface-type;
+    description
+      "ATM Sub Interface.";
+  }
+
+  identity l2vlan {
+    base iana-interface-type;
+    description
+      "Layer 2 Virtual LAN using 802.1Q.";
+  }
+  identity l3ipvlan {
+    base iana-interface-type;
+    description
+      "Layer 3 Virtual LAN using IP.";
+  }
+  identity l3ipxvlan {
+    base iana-interface-type;
+    description
+      "Layer 3 Virtual LAN using IPX.";
+  }
+  identity digitalPowerline {
+    base iana-interface-type;
+    description
+      "IP over Power Lines.";
+  }
+  identity mediaMailOverIp {
+    base iana-interface-type;
+    description
+      "Multimedia Mail over IP.";
+  }
+  identity dtm {
+    base iana-interface-type;
+    description
+      "Dynamic synchronous Transfer Mode.";
+  }
+  identity dcn {
+    base iana-interface-type;
+    description
+      "Data Communications Network.";
+  }
+  identity ipForward {
+    base iana-interface-type;
+    description
+      "IP Forwarding Interface.";
+  }
+  identity msdsl {
+    base iana-interface-type;
+    description
+      "Multi-rate Symmetric DSL.";
+  }
+  identity ieee1394 {
+    base iana-interface-type;
+
+    description
+      "IEEE1394 High Performance Serial Bus.";
+  }
+  identity if-gsn {
+    base iana-interface-type;
+    description
+      "HIPPI-6400.";
+  }
+  identity dvbRccMacLayer {
+    base iana-interface-type;
+    description
+      "DVB-RCC MAC Layer.";
+  }
+  identity dvbRccDownstream {
+    base iana-interface-type;
+    description
+      "DVB-RCC Downstream Channel.";
+  }
+  identity dvbRccUpstream {
+    base iana-interface-type;
+    description
+      "DVB-RCC Upstream Channel.";
+  }
+  identity atmVirtual {
+    base iana-interface-type;
+    description
+      "ATM Virtual Interface.";
+  }
+  identity mplsTunnel {
+    base iana-interface-type;
+    description
+      "MPLS Tunnel Virtual Interface.";
+  }
+  identity srp {
+    base iana-interface-type;
+    description
+      "Spatial Reuse Protocol.";
+  }
+  identity voiceOverAtm {
+    base iana-interface-type;
+    description
+      "Voice over ATM.";
+  }
+  identity voiceOverFrameRelay {
+    base iana-interface-type;
+    description
+      "Voice Over Frame Relay.";
+  }
+  identity idsl {
+    base iana-interface-type;
+    description
+      "Digital Subscriber Loop over ISDN.";
+  }
+  identity compositeLink {
+    base iana-interface-type;
+    description
+      "Avici Composite Link Interface.";
+  }
+  identity ss7SigLink {
+    base iana-interface-type;
+    description
+      "SS7 Signaling Link.";
+  }
+  identity propWirelessP2P {
+    base iana-interface-type;
+    description
+      "Prop. P2P wireless interface.";
+  }
+  identity frForward {
+    base iana-interface-type;
+    description
+      "Frame Forward Interface.";
+  }
+  identity rfc1483 {
+    base iana-interface-type;
+    description
+      "Multiprotocol over ATM AAL5.";
+    reference
+      "RFC 1483 - Multiprotocol Encapsulation over ATM
+                  Adaptation Layer 5";
+  }
+  identity usb {
+    base iana-interface-type;
+    description
+      "USB Interface.";
+  }
+  identity ieee8023adLag {
+    base iana-interface-type;
+    description
+      "IEEE 802.3ad Link Aggregate.";
+  }
+  identity bgppolicyaccounting {
+    base iana-interface-type;
+    description
+      "BGP Policy Accounting.";
+  }
+  identity frf16MfrBundle {
+    base iana-interface-type;
+    description
+      "FRF.16 Multilink Frame Relay.";
+  }
+  identity h323Gatekeeper {
+    base iana-interface-type;
+    description
+      "H323 Gatekeeper.";
+  }
+  identity h323Proxy {
+    base iana-interface-type;
+    description
+      "H323 Voice and Video Proxy.";
+  }
+  identity mpls {
+    base iana-interface-type;
+    description
+      "MPLS.";
+  }
+  identity mfSigLink {
+    base iana-interface-type;
+    description
+      "Multi-frequency signaling link.";
+  }
+  identity hdsl2 {
+    base iana-interface-type;
+    description
+      "High Bit-Rate DSL - 2nd generation.";
+  }
+  identity shdsl {
+    base iana-interface-type;
+    description
+      "Multirate HDSL2.";
+  }
+  identity ds1FDL {
+    base iana-interface-type;
+    description
+      "Facility Data Link (4Kbps) on a DS1.";
+  }
+  identity pos {
+    base iana-interface-type;
+    description
+      "Packet over SONET/SDH Interface.";
+  }
+
+
+
+  identity dvbAsiIn {
+    base iana-interface-type;
+    description
+      "DVB-ASI Input.";
+  }
+  identity dvbAsiOut {
+    base iana-interface-type;
+    description
+      "DVB-ASI Output.";
+  }
+  identity plc {
+    base iana-interface-type;
+    description
+      "Power Line Communications.";
+  }
+  identity nfas {
+    base iana-interface-type;
+    description
+      "Non-Facility Associated Signaling.";
+  }
+  identity tr008 {
+    base iana-interface-type;
+    description
+      "TR008.";
+  }
+  identity gr303RDT {
+    base iana-interface-type;
+    description
+      "Remote Digital Terminal.";
+  }
+  identity gr303IDT {
+    base iana-interface-type;
+    description
+      "Integrated Digital Terminal.";
+  }
+  identity isup {
+    base iana-interface-type;
+    description
+      "ISUP.";
+  }
+  identity propDocsWirelessMaclayer {
+    base iana-interface-type;
+    description
+      "Cisco proprietary Maclayer.";
+  }
+
+
+
+  identity propDocsWirelessDownstream {
+    base iana-interface-type;
+    description
+      "Cisco proprietary Downstream.";
+  }
+  identity propDocsWirelessUpstream {
+    base iana-interface-type;
+    description
+      "Cisco proprietary Upstream.";
+  }
+  identity hiperlan2 {
+    base iana-interface-type;
+    description
+      "HIPERLAN Type 2 Radio Interface.";
+  }
+  identity propBWAp2Mp {
+    base iana-interface-type;
+    description
+      "PropBroadbandWirelessAccesspt2Multipt (use of this value
+       for IEEE 802.16 WMAN interfaces as per IEEE Std 802.16f
+       is deprecated, and ieee80216WMAN(237) should be used
+       instead).";
+  }
+  identity sonetOverheadChannel {
+    base iana-interface-type;
+    description
+      "SONET Overhead Channel.";
+  }
+  identity digitalWrapperOverheadChannel {
+    base iana-interface-type;
+    description
+      "Digital Wrapper.";
+  }
+  identity aal2 {
+    base iana-interface-type;
+    description
+      "ATM adaptation layer 2.";
+  }
+  identity radioMAC {
+    base iana-interface-type;
+    description
+      "MAC layer over radio links.";
+  }
+  identity atmRadio {
+    base iana-interface-type;
+    description
+      "ATM over radio links.";
+  }
+  identity imt {
+    base iana-interface-type;
+    description
+      "Inter-Machine Trunks.";
+  }
+  identity mvl {
+    base iana-interface-type;
+    description
+      "Multiple Virtual Lines DSL.";
+  }
+  identity reachDSL {
+    base iana-interface-type;
+    description
+      "Long Reach DSL.";
+  }
+  identity frDlciEndPt {
+    base iana-interface-type;
+    description
+      "Frame Relay DLCI End Point.";
+  }
+  identity atmVciEndPt {
+    base iana-interface-type;
+    description
+      "ATM VCI End Point.";
+  }
+  identity opticalChannel {
+    base iana-interface-type;
+    description
+      "Optical Channel.";
+  }
+  identity opticalTransport {
+    base iana-interface-type;
+    description
+      "Optical Transport.";
+  }
+  identity propAtm {
+    base iana-interface-type;
+    description
+      "Proprietary ATM.";
+  }
+  identity voiceOverCable {
+    base iana-interface-type;
+    description
+      "Voice Over Cable Interface.";
+  }
+
+
+
+  identity infiniband {
+    base iana-interface-type;
+    description
+      "Infiniband.";
+  }
+  identity teLink {
+    base iana-interface-type;
+    description
+      "TE Link.";
+  }
+  identity q2931 {
+    base iana-interface-type;
+    description
+      "Q.2931.";
+  }
+  identity virtualTg {
+    base iana-interface-type;
+    description
+      "Virtual Trunk Group.";
+  }
+  identity sipTg {
+    base iana-interface-type;
+    description
+      "SIP Trunk Group.";
+  }
+  identity sipSig {
+    base iana-interface-type;
+    description
+      "SIP Signaling.";
+  }
+  identity docsCableUpstreamChannel {
+    base iana-interface-type;
+    description
+      "CATV Upstream Channel.";
+  }
+  identity econet {
+    base iana-interface-type;
+    description
+      "Acorn Econet.";
+  }
+  identity pon155 {
+    base iana-interface-type;
+    description
+      "FSAN 155Mb Symetrical PON interface.";
+  }
+
+
+
+  identity pon622 {
+    base iana-interface-type;
+    description
+      "FSAN 622Mb Symetrical PON interface.";
+  }
+  identity bridge {
+    base iana-interface-type;
+    description
+      "Transparent bridge interface.";
+  }
+  identity linegroup {
+    base iana-interface-type;
+    description
+      "Interface common to multiple lines.";
+  }
+  identity voiceEMFGD {
+    base iana-interface-type;
+    description
+      "Voice E&M Feature Group D.";
+  }
+  identity voiceFGDEANA {
+    base iana-interface-type;
+    description
+      "Voice FGD Exchange Access North American.";
+  }
+  identity voiceDID {
+    base iana-interface-type;
+    description
+      "Voice Direct Inward Dialing.";
+  }
+  identity mpegTransport {
+    base iana-interface-type;
+    description
+      "MPEG transport interface.";
+  }
+  identity sixToFour {
+    base iana-interface-type;
+    status deprecated;
+    description
+      "6to4 interface (DEPRECATED).";
+    reference
+      "RFC 4087 - IP Tunnel MIB";
+  }
+  identity gtp {
+    base iana-interface-type;
+    description
+      "GTP (GPRS Tunneling Protocol).";
+  }
+  identity pdnEtherLoop1 {
+    base iana-interface-type;
+    description
+      "Paradyne EtherLoop 1.";
+  }
+  identity pdnEtherLoop2 {
+    base iana-interface-type;
+    description
+      "Paradyne EtherLoop 2.";
+  }
+  identity opticalChannelGroup {
+    base iana-interface-type;
+    description
+      "Optical Channel Group.";
+  }
+  identity homepna {
+    base iana-interface-type;
+    description
+      "HomePNA ITU-T G.989.";
+  }
+  identity gfp {
+    base iana-interface-type;
+    description
+      "Generic Framing Procedure (GFP).";
+  }
+  identity ciscoISLvlan {
+    base iana-interface-type;
+    description
+      "Layer 2 Virtual LAN using Cisco ISL.";
+  }
+  identity actelisMetaLOOP {
+    base iana-interface-type;
+    description
+      "Acteleis proprietary MetaLOOP High Speed Link.";
+  }
+  identity fcipLink {
+    base iana-interface-type;
+    description
+      "FCIP Link.";
+  }
+  identity rpr {
+    base iana-interface-type;
+    description
+      "Resilient Packet Ring Interface Type.";
+  }
+
+
+
+  identity qam {
+    base iana-interface-type;
+    description
+      "RF Qam Interface.";
+  }
+  identity lmp {
+    base iana-interface-type;
+    description
+      "Link Management Protocol.";
+    reference
+      "RFC 4327 - Link Management Protocol (LMP) Management
+                  Information Base (MIB)";
+  }
+  identity cblVectaStar {
+    base iana-interface-type;
+    description
+      "Cambridge Broadband Networks Limited VectaStar.";
+  }
+  identity docsCableMCmtsDownstream {
+    base iana-interface-type;
+    description
+      "CATV Modular CMTS Downstream Interface.";
+  }
+  identity adsl2 {
+    base iana-interface-type;
+    status deprecated;
+    description
+      "Asymmetric Digital Subscriber Loop Version 2
+       (DEPRECATED/OBSOLETED - please use adsl2plus(238)
+       instead).";
+    reference
+      "RFC 4706 - Definitions of Managed Objects for Asymmetric
+                  Digital Subscriber Line 2 (ADSL2)";
+  }
+  identity macSecControlledIF {
+    base iana-interface-type;
+    description
+      "MACSecControlled.";
+  }
+  identity macSecUncontrolledIF {
+    base iana-interface-type;
+    description
+      "MACSecUncontrolled.";
+  }
+  identity aviciOpticalEther {
+    base iana-interface-type;
+    description
+      "Avici Optical Ethernet Aggregate.";
+  }
+  identity atmbond {
+    base iana-interface-type;
+    description
+      "atmbond.";
+  }
+  identity voiceFGDOS {
+    base iana-interface-type;
+    description
+      "Voice FGD Operator Services.";
+  }
+  identity mocaVersion1 {
+    base iana-interface-type;
+    description
+      "MultiMedia over Coax Alliance (MoCA) Interface
+       as documented in information provided privately to IANA.";
+  }
+  identity ieee80216WMAN {
+    base iana-interface-type;
+    description
+      "IEEE 802.16 WMAN interface.";
+  }
+  identity adsl2plus {
+    base iana-interface-type;
+    description
+      "Asymmetric Digital Subscriber Loop Version 2 -
+       Version 2 Plus and all variants.";
+  }
+  identity dvbRcsMacLayer {
+    base iana-interface-type;
+    description
+      "DVB-RCS MAC Layer.";
+    reference
+      "RFC 5728 - The SatLabs Group DVB-RCS MIB";
+  }
+  identity dvbTdm {
+    base iana-interface-type;
+    description
+      "DVB Satellite TDM.";
+    reference
+      "RFC 5728 - The SatLabs Group DVB-RCS MIB";
+  }
+  identity dvbRcsTdma {
+    base iana-interface-type;
+    description
+      "DVB-RCS TDMA.";
+    reference
+      "RFC 5728 - The SatLabs Group DVB-RCS MIB";
+  }
+  identity x86Laps {
+    base iana-interface-type;
+    description
+      "LAPS based on ITU-T X.86/Y.1323.";
+  }
+  identity wwanPP {
+    base iana-interface-type;
+    description
+      "3GPP WWAN.";
+  }
+  identity wwanPP2 {
+    base iana-interface-type;
+    description
+      "3GPP2 WWAN.";
+  }
+  identity voiceEBS {
+    base iana-interface-type;
+    description
+      "Voice P-phone EBS physical interface.";
+  }
+  identity ifPwType {
+    base iana-interface-type;
+    description
+      "Pseudowire interface type.";
+    reference
+      "RFC 5601 - Pseudowire (PW) Management Information Base (MIB)";
+  }
+  identity ilan {
+    base iana-interface-type;
+    description
+      "Internal LAN on a bridge per IEEE 802.1ap.";
+  }
+  identity pip {
+    base iana-interface-type;
+    description
+      "Provider Instance Port on a bridge per IEEE 802.1ah PBB.";
+  }
+  identity aluELP {
+    base iana-interface-type;
+    description
+      "Alcatel-Lucent Ethernet Link Protection.";
+  }
+  identity gpon {
+    base iana-interface-type;
+    description
+      "Gigabit-capable passive optical networks (G-PON) as per
+       ITU-T G.948.";
+  }
+  identity vdsl2 {
+    base iana-interface-type;
+    description
+      "Very high speed digital subscriber line Version 2
+       (as per ITU-T Recommendation G.993.2).";
+    reference
+      "RFC 5650 - Definitions of Managed Objects for Very High
+                  Speed Digital Subscriber Line 2 (VDSL2)";
+  }
+  identity capwapDot11Profile {
+    base iana-interface-type;
+    description
+      "WLAN Profile Interface.";
+    reference
+      "RFC 5834 - Control and Provisioning of Wireless Access
+                  Points (CAPWAP) Protocol Binding MIB for
+                  IEEE 802.11";
+  }
+  identity capwapDot11Bss {
+    base iana-interface-type;
+    description
+      "WLAN BSS Interface.";
+    reference
+      "RFC 5834 - Control and Provisioning of Wireless Access
+                  Points (CAPWAP) Protocol Binding MIB for
+                  IEEE 802.11";
+  }
+  identity capwapWtpVirtualRadio {
+    base iana-interface-type;
+    description
+      "WTP Virtual Radio Interface.";
+    reference
+      "RFC 5833 - Control and Provisioning of Wireless Access
+                  Points (CAPWAP) Protocol Base MIB";
+  }
+  identity bits {
+    base iana-interface-type;
+    description
+      "bitsport.";
+  }
+  identity docsCableUpstreamRfPort {
+    base iana-interface-type;
+    description
+      "DOCSIS CATV Upstream RF Port.";
+  }
+
+
+  identity cableDownstreamRfPort {
+    base iana-interface-type;
+    description
+      "CATV downstream RF Port.";
+  }
+  identity vmwareVirtualNic {
+    base iana-interface-type;
+    description
+      "VMware Virtual Network Interface.";
+  }
+  identity ieee802154 {
+    base iana-interface-type;
+    description
+      "IEEE 802.15.4 WPAN interface.";
+    reference
+      "IEEE 802.15.4-2006";
+  }
+  identity otnOdu {
+    base iana-interface-type;
+    description
+      "OTN Optical Data Unit.";
+  }
+  identity otnOtu {
+    base iana-interface-type;
+    description
+      "OTN Optical channel Transport Unit.";
+  }
+  identity ifVfiType {
+    base iana-interface-type;
+    description
+      "VPLS Forwarding Instance Interface Type.";
+  }
+  identity g9981 {
+    base iana-interface-type;
+    description
+      "G.998.1 bonded interface.";
+  }
+  identity g9982 {
+    base iana-interface-type;
+    description
+      "G.998.2 bonded interface.";
+  }
+  identity g9983 {
+    base iana-interface-type;
+    description
+      "G.998.3 bonded interface.";
+  }
+
+  identity aluEpon {
+    base iana-interface-type;
+    description
+      "Ethernet Passive Optical Networks (E-PON).";
+  }
+  identity aluEponOnu {
+    base iana-interface-type;
+    description
+      "EPON Optical Network Unit.";
+  }
+  identity aluEponPhysicalUni {
+    base iana-interface-type;
+    description
+      "EPON physical User to Network interface.";
+  }
+  identity aluEponLogicalLink {
+    base iana-interface-type;
+    description
+      "The emulation of a point-to-point link over the EPON
+       layer.";
+  }
+  identity aluGponOnu {
+    base iana-interface-type;
+    description
+      "GPON Optical Network Unit.";
+    reference
+      "ITU-T G.984.2";
+  }
+  identity aluGponPhysicalUni {
+    base iana-interface-type;
+    description
+      "GPON physical User to Network interface.";
+    reference
+      "ITU-T G.984.2";
+  }
+  identity vmwareNicTeam {
+    base iana-interface-type;
+    description
+      "VMware NIC Team.";
+  }
+}
diff --git a/tools/lint/examples/ietf-interfaces.yang b/tools/lint/examples/ietf-interfaces.yang
new file mode 100644
index 0000000..ad64425
--- /dev/null
+++ b/tools/lint/examples/ietf-interfaces.yang
@@ -0,0 +1,725 @@
+module ietf-interfaces {
+
+  namespace "urn:ietf:params:xml:ns:yang:ietf-interfaces";
+  prefix if;
+
+  import ietf-yang-types {
+    prefix yang;
+  }
+
+  organization
+    "IETF NETMOD (NETCONF Data Modeling Language) Working Group";
+
+  contact
+    "WG Web:   <http://tools.ietf.org/wg/netmod/>
+     WG List:  <mailto:netmod@ietf.org>
+
+     WG Chair: Thomas Nadeau
+               <mailto:tnadeau@lucidvision.com>
+
+     WG Chair: Juergen Schoenwaelder
+               <mailto:j.schoenwaelder@jacobs-university.de>
+
+     Editor:   Martin Bjorklund
+               <mailto:mbj@tail-f.com>";
+
+  description
+    "This module contains a collection of YANG definitions for
+     managing network interfaces.
+
+     Copyright (c) 2014 IETF Trust and the persons identified as
+     authors of the code.  All rights reserved.
+
+     Redistribution and use in source and binary forms, with or
+     without modification, is permitted pursuant to, and subject
+     to the license terms contained in, the Simplified BSD License
+     set forth in Section 4.c of the IETF Trust's Legal Provisions
+     Relating to IETF Documents
+     (http://trustee.ietf.org/license-info).
+
+     This version of this YANG module is part of RFC 7223; see
+     the RFC itself for full legal notices.";
+
+  revision 2014-05-08 {
+    description
+      "Initial revision.";
+    reference
+      "RFC 7223: A YANG Data Model for Interface Management";
+  }
+
+  /*
+   * Typedefs
+   */
+
+  typedef interface-ref {
+    type leafref {
+      path "/if:interfaces/if:interface/if:name";
+    }
+    description
+      "This type is used by data models that need to reference
+       configured interfaces.";
+  }
+
+  typedef interface-state-ref {
+    type leafref {
+      path "/if:interfaces-state/if:interface/if:name";
+    }
+    description
+      "This type is used by data models that need to reference
+       the operationally present interfaces.";
+  }
+
+  /*
+   * Identities
+   */
+
+  identity interface-type {
+    description
+      "Base identity from which specific interface types are
+       derived.";
+  }
+
+  /*
+   * Features
+   */
+
+  feature arbitrary-names {
+    description
+      "This feature indicates that the device allows user-controlled
+       interfaces to be named arbitrarily.";
+  }
+  feature pre-provisioning {
+    description
+      "This feature indicates that the device supports
+       pre-provisioning of interface configuration, i.e., it is
+       possible to configure an interface whose physical interface
+       hardware is not present on the device.";
+  }
+
+  feature if-mib {
+    description
+      "This feature indicates that the device implements
+       the IF-MIB.";
+    reference
+      "RFC 2863: The Interfaces Group MIB";
+  }
+
+  /*
+   * Configuration data nodes
+   */
+
+  container interfaces {
+    description
+      "Interface configuration parameters.";
+
+    list interface {
+      key "name";
+
+      description
+        "The list of configured interfaces on the device.
+
+         The operational state of an interface is available in the
+         /interfaces-state/interface list.  If the configuration of a
+         system-controlled interface cannot be used by the system
+         (e.g., the interface hardware present does not match the
+         interface type), then the configuration is not applied to
+         the system-controlled interface shown in the
+         /interfaces-state/interface list.  If the configuration
+         of a user-controlled interface cannot be used by the system,
+         the configured interface is not instantiated in the
+         /interfaces-state/interface list.";
+
+     leaf name {
+        type string;
+        description
+          "The name of the interface.
+
+           A device MAY restrict the allowed values for this leaf,
+           possibly depending on the type of the interface.
+           For system-controlled interfaces, this leaf is the
+           device-specific name of the interface.  The 'config false'
+           list /interfaces-state/interface contains the currently
+           existing interfaces on the device.
+
+           If a client tries to create configuration for a
+           system-controlled interface that is not present in the
+           /interfaces-state/interface list, the server MAY reject
+           the request if the implementation does not support
+           pre-provisioning of interfaces or if the name refers to
+           an interface that can never exist in the system.  A
+           NETCONF server MUST reply with an rpc-error with the
+           error-tag 'invalid-value' in this case.
+
+           If the device supports pre-provisioning of interface
+           configuration, the 'pre-provisioning' feature is
+           advertised.
+
+           If the device allows arbitrarily named user-controlled
+           interfaces, the 'arbitrary-names' feature is advertised.
+
+           When a configured user-controlled interface is created by
+           the system, it is instantiated with the same name in the
+           /interface-state/interface list.";
+      }
+
+      leaf description {
+        type string;
+        description
+          "A textual description of the interface.
+
+           A server implementation MAY map this leaf to the ifAlias
+           MIB object.  Such an implementation needs to use some
+           mechanism to handle the differences in size and characters
+           allowed between this leaf and ifAlias.  The definition of
+           such a mechanism is outside the scope of this document.
+
+           Since ifAlias is defined to be stored in non-volatile
+           storage, the MIB implementation MUST map ifAlias to the
+           value of 'description' in the persistently stored
+           datastore.
+
+           Specifically, if the device supports ':startup', when
+           ifAlias is read the device MUST return the value of
+           'description' in the 'startup' datastore, and when it is
+           written, it MUST be written to the 'running' and 'startup'
+           datastores.  Note that it is up to the implementation to
+
+           decide whether to modify this single leaf in 'startup' or
+           perform an implicit copy-config from 'running' to
+           'startup'.
+
+           If the device does not support ':startup', ifAlias MUST
+           be mapped to the 'description' leaf in the 'running'
+           datastore.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifAlias";
+      }
+
+      leaf type {
+        type identityref {
+          base interface-type;
+        }
+        mandatory true;
+        description
+          "The type of the interface.
+
+           When an interface entry is created, a server MAY
+           initialize the type leaf with a valid value, e.g., if it
+           is possible to derive the type from the name of the
+           interface.
+
+           If a client tries to set the type of an interface to a
+           value that can never be used by the system, e.g., if the
+           type is not supported or if the type does not match the
+           name of the interface, the server MUST reject the request.
+           A NETCONF server MUST reply with an rpc-error with the
+           error-tag 'invalid-value' in this case.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifType";
+      }
+
+      leaf enabled {
+        type boolean;
+        default "true";
+        description
+          "This leaf contains the configured, desired state of the
+           interface.
+
+           Systems that implement the IF-MIB use the value of this
+           leaf in the 'running' datastore to set
+           IF-MIB.ifAdminStatus to 'up' or 'down' after an ifEntry
+           has been initialized, as described in RFC 2863.
+
+
+
+           Changes in this leaf in the 'running' datastore are
+           reflected in ifAdminStatus, but if ifAdminStatus is
+           changed over SNMP, this leaf is not affected.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifAdminStatus";
+      }
+
+      leaf link-up-down-trap-enable {
+        if-feature if-mib;
+        type enumeration {
+          enum enabled {
+            value 1;
+          }
+          enum disabled {
+            value 2;
+          }
+        }
+        description
+          "Controls whether linkUp/linkDown SNMP notifications
+           should be generated for this interface.
+
+           If this node is not configured, the value 'enabled' is
+           operationally used by the server for interfaces that do
+           not operate on top of any other interface (i.e., there are
+           no 'lower-layer-if' entries), and 'disabled' otherwise.";
+        reference
+          "RFC 2863: The Interfaces Group MIB -
+                     ifLinkUpDownTrapEnable";
+      }
+    }
+  }
+
+  /*
+   * Operational state data nodes
+   */
+
+  container interfaces-state {
+    config false;
+    description
+      "Data nodes for the operational state of interfaces.";
+
+    list interface {
+      key "name";
+
+
+
+
+
+      description
+        "The list of interfaces on the device.
+
+         System-controlled interfaces created by the system are
+         always present in this list, whether they are configured or
+         not.";
+
+      leaf name {
+        type string;
+        description
+          "The name of the interface.
+
+           A server implementation MAY map this leaf to the ifName
+           MIB object.  Such an implementation needs to use some
+           mechanism to handle the differences in size and characters
+           allowed between this leaf and ifName.  The definition of
+           such a mechanism is outside the scope of this document.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifName";
+      }
+
+      leaf type {
+        type identityref {
+          base interface-type;
+        }
+        mandatory true;
+        description
+          "The type of the interface.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifType";
+      }
+
+      leaf admin-status {
+        if-feature if-mib;
+        type enumeration {
+          enum up {
+            value 1;
+            description
+              "Ready to pass packets.";
+          }
+          enum down {
+            value 2;
+            description
+              "Not ready to pass packets and not in some test mode.";
+          }
+
+
+
+          enum testing {
+            value 3;
+            description
+              "In some test mode.";
+          }
+        }
+        mandatory true;
+        description
+          "The desired state of the interface.
+
+           This leaf has the same read semantics as ifAdminStatus.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifAdminStatus";
+      }
+
+      leaf oper-status {
+        type enumeration {
+          enum up {
+            value 1;
+            description
+              "Ready to pass packets.";
+          }
+          enum down {
+            value 2;
+            description
+              "The interface does not pass any packets.";
+          }
+          enum testing {
+            value 3;
+            description
+              "In some test mode.  No operational packets can
+               be passed.";
+          }
+          enum unknown {
+            value 4;
+            description
+              "Status cannot be determined for some reason.";
+          }
+          enum dormant {
+            value 5;
+            description
+              "Waiting for some external event.";
+          }
+          enum not-present {
+            value 6;
+            description
+              "Some component (typically hardware) is missing.";
+          }
+          enum lower-layer-down {
+            value 7;
+            description
+              "Down due to state of lower-layer interface(s).";
+          }
+        }
+        mandatory true;
+        description
+          "The current operational state of the interface.
+
+           This leaf has the same semantics as ifOperStatus.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifOperStatus";
+      }
+
+      leaf last-change {
+        type yang:date-and-time;
+        description
+          "The time the interface entered its current operational
+           state.  If the current state was entered prior to the
+           last re-initialization of the local network management
+           subsystem, then this node is not present.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifLastChange";
+      }
+
+      leaf if-index {
+        if-feature if-mib;
+        type int32 {
+          range "1..2147483647";
+        }
+        mandatory true;
+        description
+          "The ifIndex value for the ifEntry represented by this
+           interface.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifIndex";
+      }
+
+      leaf phys-address {
+        type yang:phys-address;
+        description
+          "The interface's address at its protocol sub-layer.  For
+           example, for an 802.x interface, this object normally
+           contains a Media Access Control (MAC) address.  The
+           interface's media-specific modules must define the bit
+
+
+           and byte ordering and the format of the value of this
+           object.  For interfaces that do not have such an address
+           (e.g., a serial line), this node is not present.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifPhysAddress";
+      }
+
+      leaf-list higher-layer-if {
+        type interface-state-ref;
+        description
+          "A list of references to interfaces layered on top of this
+           interface.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifStackTable";
+      }
+
+      leaf-list lower-layer-if {
+        type interface-state-ref;
+        description
+          "A list of references to interfaces layered underneath this
+           interface.";
+        reference
+          "RFC 2863: The Interfaces Group MIB - ifStackTable";
+      }
+
+      leaf speed {
+        type yang:gauge64;
+        units "bits/second";
+        description
+            "An estimate of the interface's current bandwidth in bits
+             per second.  For interfaces that do not vary in
+             bandwidth or for those where no accurate estimation can
+             be made, this node should contain the nominal bandwidth.
+             For interfaces that have no concept of bandwidth, this
+             node is not present.";
+        reference
+          "RFC 2863: The Interfaces Group MIB -
+                     ifSpeed, ifHighSpeed";
+      }
+
+
+
+
+
+
+
+
+
+      container statistics {
+        description
+          "A collection of interface-related statistics objects.";
+
+        leaf discontinuity-time {
+          type yang:date-and-time;
+          mandatory true;
+          description
+            "The time on the most recent occasion at which any one or
+             more of this interface's counters suffered a
+             discontinuity.  If no such discontinuities have occurred
+             since the last re-initialization of the local management
+             subsystem, then this node contains the time the local
+             management subsystem re-initialized itself.";
+        }
+
+        leaf in-octets {
+          type yang:counter64;
+          description
+            "The total number of octets received on the interface,
+             including framing characters.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifHCInOctets";
+        }
+
+        leaf in-unicast-pkts {
+          type yang:counter64;
+          description
+            "The number of packets, delivered by this sub-layer to a
+             higher (sub-)layer, that were not addressed to a
+             multicast or broadcast address at this sub-layer.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifHCInUcastPkts";
+        }
+
+
+
+
+        leaf in-broadcast-pkts {
+          type yang:counter64;
+          description
+            "The number of packets, delivered by this sub-layer to a
+             higher (sub-)layer, that were addressed to a broadcast
+             address at this sub-layer.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB -
+                       ifHCInBroadcastPkts";
+        }
+
+        leaf in-multicast-pkts {
+          type yang:counter64;
+          description
+            "The number of packets, delivered by this sub-layer to a
+             higher (sub-)layer, that were addressed to a multicast
+             address at this sub-layer.  For a MAC-layer protocol,
+             this includes both Group and Functional addresses.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB -
+                       ifHCInMulticastPkts";
+        }
+
+        leaf in-discards {
+          type yang:counter32;
+          description
+            "The number of inbound packets that were chosen to be
+             discarded even though no errors had been detected to
+             prevent their being deliverable to a higher-layer
+             protocol.  One possible reason for discarding such a
+             packet could be to free up buffer space.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+
+
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifInDiscards";
+        }
+
+        leaf in-errors {
+          type yang:counter32;
+          description
+            "For packet-oriented interfaces, the number of inbound
+             packets that contained errors preventing them from being
+             deliverable to a higher-layer protocol.  For character-
+             oriented or fixed-length interfaces, the number of
+             inbound transmission units that contained errors
+             preventing them from being deliverable to a higher-layer
+             protocol.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifInErrors";
+        }
+
+        leaf in-unknown-protos {
+          type yang:counter32;
+          description
+            "For packet-oriented interfaces, the number of packets
+             received via the interface that were discarded because
+             of an unknown or unsupported protocol.  For
+             character-oriented or fixed-length interfaces that
+             support protocol multiplexing, the number of
+             transmission units received via the interface that were
+             discarded because of an unknown or unsupported protocol.
+             For any interface that does not support protocol
+             multiplexing, this counter is not present.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifInUnknownProtos";
+        }
+
+
+
+
+
+        leaf out-octets {
+          type yang:counter64;
+          description
+            "The total number of octets transmitted out of the
+             interface, including framing characters.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifHCOutOctets";
+        }
+
+        leaf out-unicast-pkts {
+          type yang:counter64;
+          description
+            "The total number of packets that higher-level protocols
+             requested be transmitted, and that were not addressed
+             to a multicast or broadcast address at this sub-layer,
+             including those that were discarded or not sent.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifHCOutUcastPkts";
+        }
+
+        leaf out-broadcast-pkts {
+          type yang:counter64;
+          description
+            "The total number of packets that higher-level protocols
+             requested be transmitted, and that were addressed to a
+             broadcast address at this sub-layer, including those
+             that were discarded or not sent.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB -
+                       ifHCOutBroadcastPkts";
+        }
+
+
+        leaf out-multicast-pkts {
+          type yang:counter64;
+          description
+            "The total number of packets that higher-level protocols
+             requested be transmitted, and that were addressed to a
+             multicast address at this sub-layer, including those
+             that were discarded or not sent.  For a MAC-layer
+             protocol, this includes both Group and Functional
+             addresses.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB -
+                       ifHCOutMulticastPkts";
+        }
+
+        leaf out-discards {
+          type yang:counter32;
+          description
+            "The number of outbound packets that were chosen to be
+             discarded even though no errors had been detected to
+             prevent their being transmitted.  One possible reason
+             for discarding such a packet could be to free up buffer
+             space.
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifOutDiscards";
+        }
+
+        leaf out-errors {
+          type yang:counter32;
+          description
+            "For packet-oriented interfaces, the number of outbound
+             packets that could not be transmitted because of errors.
+             For character-oriented or fixed-length interfaces, the
+             number of outbound transmission units that could not be
+             transmitted because of errors.
+
+
+
+
+             Discontinuities in the value of this counter can occur
+             at re-initialization of the management system, and at
+             other times as indicated by the value of
+             'discontinuity-time'.";
+          reference
+            "RFC 2863: The Interfaces Group MIB - ifOutErrors";
+        }
+      }
+    }
+  }
+}
diff --git a/tools/lint/examples/ietf-ip.yang b/tools/lint/examples/ietf-ip.yang
new file mode 100644
index 0000000..1499120
--- /dev/null
+++ b/tools/lint/examples/ietf-ip.yang
@@ -0,0 +1,758 @@
+module ietf-ip {
+
+ namespace "urn:ietf:params:xml:ns:yang:ietf-ip";
+ prefix ip;
+
+ import ietf-interfaces {
+   prefix if;
+ }
+ import ietf-inet-types {
+   prefix inet;
+ }
+ import ietf-yang-types {
+   prefix yang;
+ }
+
+ organization
+   "IETF NETMOD (NETCONF Data Modeling Language) Working Group";
+
+ contact
+   "WG Web:   <http://tools.ietf.org/wg/netmod/>
+    WG List:  <mailto:netmod@ietf.org>
+
+    WG Chair: Thomas Nadeau
+              <mailto:tnadeau@lucidvision.com>
+
+    WG Chair: Juergen Schoenwaelder
+              <mailto:j.schoenwaelder@jacobs-university.de>
+
+    Editor:   Martin Bjorklund
+              <mailto:mbj@tail-f.com>";
+
+
+
+
+
+
+
+
+
+
+ description
+   "This module contains a collection of YANG definitions for
+    configuring IP implementations.
+
+    Copyright (c) 2014 IETF Trust and the persons identified as
+    authors of the code.  All rights reserved.
+
+    Redistribution and use in source and binary forms, with or
+    without modification, is permitted pursuant to, and subject
+    to the license terms contained in, the Simplified BSD License
+    set forth in Section 4.c of the IETF Trust's Legal Provisions
+    Relating to IETF Documents
+    (http://trustee.ietf.org/license-info).
+
+    This version of this YANG module is part of RFC 7277; see
+    the RFC itself for full legal notices.";
+
+ revision 2014-06-16 {
+   description
+     "Initial revision.";
+   reference
+     "RFC 7277: A YANG Data Model for IP Management";
+ }
+
+ /*
+
+  * Features
+  */
+
+ feature ipv4-non-contiguous-netmasks {
+   description
+     "Indicates support for configuring non-contiguous
+      subnet masks.";
+ }
+
+ feature ipv6-privacy-autoconf {
+   description
+     "Indicates support for Privacy Extensions for Stateless Address
+      Autoconfiguration in IPv6.";
+   reference
+     "RFC 4941: Privacy Extensions for Stateless Address
+                Autoconfiguration in IPv6";
+ }
+
+
+
+
+
+ /*
+  * Typedefs
+  */
+
+ typedef ip-address-origin {
+   type enumeration {
+     enum other {
+       description
+         "None of the following.";
+     }
+     enum static {
+       description
+         "Indicates that the address has been statically
+          configured - for example, using NETCONF or a Command Line
+          Interface.";
+     }
+     enum dhcp {
+       description
+         "Indicates an address that has been assigned to this
+          system by a DHCP server.";
+     }
+     enum link-layer {
+       description
+         "Indicates an address created by IPv6 stateless
+          autoconfiguration that embeds a link-layer address in its
+          interface identifier.";
+     }
+     enum random {
+       description
+         "Indicates an address chosen by the system at
+
+          random, e.g., an IPv4 address within 169.254/16, an
+          RFC 4941 temporary address, or an RFC 7217 semantically
+          opaque address.";
+       reference
+         "RFC 4941: Privacy Extensions for Stateless Address
+                    Autoconfiguration in IPv6
+          RFC 7217: A Method for Generating Semantically Opaque
+                    Interface Identifiers with IPv6 Stateless
+                    Address Autoconfiguration (SLAAC)";
+     }
+   }
+   description
+     "The origin of an address.";
+ }
+
+
+
+ typedef neighbor-origin {
+   type enumeration {
+     enum other {
+       description
+         "None of the following.";
+     }
+     enum static {
+       description
+         "Indicates that the mapping has been statically
+          configured - for example, using NETCONF or a Command Line
+          Interface.";
+     }
+     enum dynamic {
+       description
+         "Indicates that the mapping has been dynamically resolved
+          using, e.g., IPv4 ARP or the IPv6 Neighbor Discovery
+          protocol.";
+     }
+   }
+   description
+     "The origin of a neighbor entry.";
+ }
+
+ /*
+  * Configuration data nodes
+  */
+
+ augment "/if:interfaces/if:interface" {
+   description
+     "Parameters for configuring IP on interfaces.
+
+      If an interface is not capable of running IP, the server
+      must not allow the client to configure these parameters.";
+
+   container ipv4 {
+     presence
+       "Enables IPv4 unless the 'enabled' leaf
+        (which defaults to 'true') is set to 'false'";
+     description
+       "Parameters for the IPv4 address family.";
+
+
+
+
+
+
+
+
+     leaf enabled {
+       type boolean;
+       default true;
+       description
+         "Controls whether IPv4 is enabled or disabled on this
+          interface.  When IPv4 is enabled, this interface is
+          connected to an IPv4 stack, and the interface can send
+          and receive IPv4 packets.";
+     }
+     leaf forwarding {
+       type boolean;
+       default false;
+       description
+         "Controls IPv4 packet forwarding of datagrams received by,
+          but not addressed to, this interface.  IPv4 routers
+          forward datagrams.  IPv4 hosts do not (except those
+          source-routed via the host).";
+     }
+     leaf mtu {
+       type uint16 {
+         range "68..max";
+       }
+       units octets;
+       description
+         "The size, in octets, of the largest IPv4 packet that the
+          interface will send and receive.
+
+          The server may restrict the allowed values for this leaf,
+          depending on the interface's type.
+
+          If this leaf is not configured, the operationally used MTU
+          depends on the interface's type.";
+       reference
+         "RFC 791: Internet Protocol";
+     }
+     list address {
+       key "ip";
+       description
+         "The list of configured IPv4 addresses on the interface.";
+
+       leaf ip {
+         type inet:ipv4-address-no-zone;
+         description
+           "The IPv4 address on the interface.";
+       }
+
+
+
+       choice subnet {
+         mandatory true;
+         description
+           "The subnet can be specified as a prefix-length, or,
+            if the server supports non-contiguous netmasks, as
+            a netmask.";
+         leaf prefix-length {
+           type uint8 {
+             range "0..32";
+           }
+           description
+             "The length of the subnet prefix.";
+         }
+         leaf netmask {
+           if-feature ipv4-non-contiguous-netmasks;
+           type yang:dotted-quad;
+           description
+             "The subnet specified as a netmask.";
+         }
+       }
+     }
+     list neighbor {
+       key "ip";
+       description
+         "A list of mappings from IPv4 addresses to
+          link-layer addresses.
+
+          Entries in this list are used as static entries in the
+          ARP Cache.";
+       reference
+         "RFC 826: An Ethernet Address Resolution Protocol";
+
+       leaf ip {
+         type inet:ipv4-address-no-zone;
+         description
+           "The IPv4 address of the neighbor node.";
+       }
+       leaf link-layer-address {
+         type yang:phys-address;
+         mandatory true;
+         description
+           "The link-layer address of the neighbor node.";
+       }
+     }
+
+   }
+
+
+   container ipv6 {
+     presence
+       "Enables IPv6 unless the 'enabled' leaf
+        (which defaults to 'true') is set to 'false'";
+     description
+       "Parameters for the IPv6 address family.";
+
+     leaf enabled {
+       type boolean;
+       default true;
+       description
+         "Controls whether IPv6 is enabled or disabled on this
+          interface.  When IPv6 is enabled, this interface is
+          connected to an IPv6 stack, and the interface can send
+          and receive IPv6 packets.";
+     }
+     leaf forwarding {
+       type boolean;
+       default false;
+       description
+         "Controls IPv6 packet forwarding of datagrams received by,
+          but not addressed to, this interface.  IPv6 routers
+          forward datagrams.  IPv6 hosts do not (except those
+          source-routed via the host).";
+       reference
+         "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)
+                    Section 6.2.1, IsRouter";
+     }
+     leaf mtu {
+       type uint32 {
+         range "1280..max";
+       }
+       units octets;
+       description
+         "The size, in octets, of the largest IPv6 packet that the
+          interface will send and receive.
+
+          The server may restrict the allowed values for this leaf,
+          depending on the interface's type.
+
+          If this leaf is not configured, the operationally used MTU
+          depends on the interface's type.";
+       reference
+         "RFC 2460: Internet Protocol, Version 6 (IPv6) Specification
+                    Section 5";
+     }
+
+
+     list address {
+       key "ip";
+       description
+         "The list of configured IPv6 addresses on the interface.";
+
+       leaf ip {
+         type inet:ipv6-address-no-zone;
+         description
+           "The IPv6 address on the interface.";
+       }
+       leaf prefix-length {
+         type uint8 {
+           range "0..128";
+         }
+         mandatory true;
+         description
+           "The length of the subnet prefix.";
+       }
+     }
+     list neighbor {
+       key "ip";
+       description
+         "A list of mappings from IPv6 addresses to
+          link-layer addresses.
+
+          Entries in this list are used as static entries in the
+          Neighbor Cache.";
+       reference
+         "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)";
+
+       leaf ip {
+         type inet:ipv6-address-no-zone;
+         description
+           "The IPv6 address of the neighbor node.";
+       }
+       leaf link-layer-address {
+         type yang:phys-address;
+         mandatory true;
+         description
+           "The link-layer address of the neighbor node.";
+       }
+     }
+
+
+
+
+
+
+     leaf dup-addr-detect-transmits {
+       type uint32;
+       default 1;
+       description
+         "The number of consecutive Neighbor Solicitation messages
+          sent while performing Duplicate Address Detection on a
+          tentative address.  A value of zero indicates that
+          Duplicate Address Detection is not performed on
+          tentative addresses.  A value of one indicates a single
+          transmission with no follow-up retransmissions.";
+       reference
+         "RFC 4862: IPv6 Stateless Address Autoconfiguration";
+     }
+     container autoconf {
+       description
+         "Parameters to control the autoconfiguration of IPv6
+          addresses, as described in RFC 4862.";
+       reference
+         "RFC 4862: IPv6 Stateless Address Autoconfiguration";
+
+       leaf create-global-addresses {
+         type boolean;
+         default true;
+         description
+           "If enabled, the host creates global addresses as
+            described in RFC 4862.";
+         reference
+           "RFC 4862: IPv6 Stateless Address Autoconfiguration
+                      Section 5.5";
+       }
+       leaf create-temporary-addresses {
+         if-feature ipv6-privacy-autoconf;
+         type boolean;
+         default false;
+         description
+           "If enabled, the host creates temporary addresses as
+            described in RFC 4941.";
+         reference
+           "RFC 4941: Privacy Extensions for Stateless Address
+                      Autoconfiguration in IPv6";
+       }
+
+
+
+
+
+
+
+       leaf temporary-valid-lifetime {
+         if-feature ipv6-privacy-autoconf;
+         type uint32;
+         units "seconds";
+         default 604800;
+         description
+           "The time period during which the temporary address
+            is valid.";
+         reference
+           "RFC 4941: Privacy Extensions for Stateless Address
+                      Autoconfiguration in IPv6
+                      - TEMP_VALID_LIFETIME";
+       }
+       leaf temporary-preferred-lifetime {
+         if-feature ipv6-privacy-autoconf;
+         type uint32;
+         units "seconds";
+         default 86400;
+         description
+           "The time period during which the temporary address is
+            preferred.";
+         reference
+           "RFC 4941: Privacy Extensions for Stateless Address
+                      Autoconfiguration in IPv6
+                      - TEMP_PREFERRED_LIFETIME";
+       }
+     }
+   }
+ }
+
+ /*
+  * Operational state data nodes
+  */
+
+ augment "/if:interfaces-state/if:interface" {
+   description
+     "Data nodes for the operational state of IP on interfaces.";
+
+   container ipv4 {
+     presence "Present if IPv4 is enabled on this interface";
+     config false;
+     description
+       "Interface-specific parameters for the IPv4 address family.";
+
+
+
+
+
+     leaf forwarding {
+       type boolean;
+       description
+         "Indicates whether IPv4 packet forwarding is enabled or
+          disabled on this interface.";
+     }
+     leaf mtu {
+       type uint16 {
+         range "68..max";
+       }
+       units octets;
+       description
+         "The size, in octets, of the largest IPv4 packet that the
+          interface will send and receive.";
+       reference
+         "RFC 791: Internet Protocol";
+     }
+     list address {
+       key "ip";
+       description
+         "The list of IPv4 addresses on the interface.";
+
+       leaf ip {
+         type inet:ipv4-address-no-zone;
+         description
+           "The IPv4 address on the interface.";
+       }
+       choice subnet {
+         description
+           "The subnet can be specified as a prefix-length, or,
+            if the server supports non-contiguous netmasks, as
+            a netmask.";
+         leaf prefix-length {
+           type uint8 {
+             range "0..32";
+           }
+           description
+             "The length of the subnet prefix.";
+         }
+         leaf netmask {
+           if-feature ipv4-non-contiguous-netmasks;
+           type yang:dotted-quad;
+           description
+             "The subnet specified as a netmask.";
+         }
+       }
+
+
+       leaf origin {
+         type ip-address-origin;
+         description
+           "The origin of this address.";
+       }
+     }
+     list neighbor {
+       key "ip";
+       description
+         "A list of mappings from IPv4 addresses to
+          link-layer addresses.
+
+          This list represents the ARP Cache.";
+       reference
+         "RFC 826: An Ethernet Address Resolution Protocol";
+
+       leaf ip {
+         type inet:ipv4-address-no-zone;
+         description
+           "The IPv4 address of the neighbor node.";
+       }
+       leaf link-layer-address {
+         type yang:phys-address;
+         description
+           "The link-layer address of the neighbor node.";
+       }
+       leaf origin {
+         type neighbor-origin;
+         description
+           "The origin of this neighbor entry.";
+       }
+     }
+
+   }
+
+   container ipv6 {
+     presence "Present if IPv6 is enabled on this interface";
+     config false;
+     description
+       "Parameters for the IPv6 address family.";
+
+
+
+
+
+
+
+
+     leaf forwarding {
+       type boolean;
+       default false;
+       description
+         "Indicates whether IPv6 packet forwarding is enabled or
+          disabled on this interface.";
+       reference
+         "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)
+                    Section 6.2.1, IsRouter";
+     }
+     leaf mtu {
+       type uint32 {
+         range "1280..max";
+       }
+       units octets;
+       description
+         "The size, in octets, of the largest IPv6 packet that the
+          interface will send and receive.";
+       reference
+         "RFC 2460: Internet Protocol, Version 6 (IPv6) Specification
+                    Section 5";
+     }
+     list address {
+       key "ip";
+       description
+         "The list of IPv6 addresses on the interface.";
+
+       leaf ip {
+         type inet:ipv6-address-no-zone;
+         description
+           "The IPv6 address on the interface.";
+       }
+       leaf prefix-length {
+         type uint8 {
+           range "0..128";
+         }
+         mandatory true;
+         description
+           "The length of the subnet prefix.";
+       }
+       leaf origin {
+         type ip-address-origin;
+         description
+           "The origin of this address.";
+       }
+
+
+
+       leaf status {
+         type enumeration {
+           enum preferred {
+             description
+               "This is a valid address that can appear as the
+                destination or source address of a packet.";
+           }
+           enum deprecated {
+             description
+               "This is a valid but deprecated address that should
+                no longer be used as a source address in new
+                communications, but packets addressed to such an
+                address are processed as expected.";
+           }
+           enum invalid {
+             description
+               "This isn't a valid address, and it shouldn't appear
+                as the destination or source address of a packet.";
+           }
+           enum inaccessible {
+             description
+               "The address is not accessible because the interface
+                to which this address is assigned is not
+                operational.";
+           }
+           enum unknown {
+             description
+               "The status cannot be determined for some reason.";
+           }
+           enum tentative {
+             description
+               "The uniqueness of the address on the link is being
+                verified.  Addresses in this state should not be
+                used for general communication and should only be
+                used to determine the uniqueness of the address.";
+           }
+           enum duplicate {
+             description
+               "The address has been determined to be non-unique on
+                the link and so must not be used.";
+           }
+
+
+
+
+
+
+
+           enum optimistic {
+             description
+               "The address is available for use, subject to
+                restrictions, while its uniqueness on a link is
+                being verified.";
+           }
+         }
+         description
+           "The status of an address.  Most of the states correspond
+            to states from the IPv6 Stateless Address
+            Autoconfiguration protocol.";
+         reference
+           "RFC 4293: Management Information Base for the
+                      Internet Protocol (IP)
+                      - IpAddressStatusTC
+            RFC 4862: IPv6 Stateless Address Autoconfiguration";
+       }
+     }
+     list neighbor {
+       key "ip";
+       description
+         "A list of mappings from IPv6 addresses to
+          link-layer addresses.
+
+          This list represents the Neighbor Cache.";
+       reference
+         "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)";
+
+       leaf ip {
+         type inet:ipv6-address-no-zone;
+         description
+           "The IPv6 address of the neighbor node.";
+       }
+       leaf link-layer-address {
+         type yang:phys-address;
+         description
+           "The link-layer address of the neighbor node.";
+       }
+       leaf origin {
+         type neighbor-origin;
+         description
+           "The origin of this neighbor entry.";
+       }
+       leaf is-router {
+         type empty;
+         description
+           "Indicates that the neighbor node acts as a router.";
+       }
+       leaf state {
+         type enumeration {
+           enum incomplete {
+             description
+               "Address resolution is in progress, and the link-layer
+                address of the neighbor has not yet been
+                determined.";
+           }
+           enum reachable {
+             description
+               "Roughly speaking, the neighbor is known to have been
+                reachable recently (within tens of seconds ago).";
+           }
+           enum stale {
+             description
+               "The neighbor is no longer known to be reachable, but
+                until traffic is sent to the neighbor no attempt
+                should be made to verify its reachability.";
+           }
+           enum delay {
+             description
+               "The neighbor is no longer known to be reachable, and
+                traffic has recently been sent to the neighbor.
+                Rather than probe the neighbor immediately, however,
+                delay sending probes for a short while in order to
+                give upper-layer protocols a chance to provide
+                reachability confirmation.";
+           }
+           enum probe {
+             description
+               "The neighbor is no longer known to be reachable, and
+                unicast Neighbor Solicitation probes are being sent
+                to verify reachability.";
+           }
+         }
+         description
+           "The Neighbor Unreachability Detection state of this
+            entry.";
+         reference
+           "RFC 4861: Neighbor Discovery for IP version 6 (IPv6)
+                      Section 7.3.2";
+       }
+     }
+   }
+ }
+}
diff --git a/tools/lint/examples/ietf-netconf-acm-when.yang b/tools/lint/examples/ietf-netconf-acm-when.yang
new file mode 100644
index 0000000..902fcbf
--- /dev/null
+++ b/tools/lint/examples/ietf-netconf-acm-when.yang
@@ -0,0 +1,412 @@
+module ietf-netconf-acm-when {
+  namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-acm";
+  prefix nacm;
+
+  import ietf-yang-types {
+    prefix yang;
+  }
+
+  organization
+    "IETF NETCONF (Network Configuration) Working Group";
+  contact
+    "WG Web:   <http://tools.ietf.org/wg/netconf/>
+     WG List:  <mailto:netconf@ietf.org>
+     
+     WG Chair: Mehmet Ersue
+               <mailto:mehmet.ersue@nsn.com>
+     
+     WG Chair: Bert Wijnen
+               <mailto:bertietf@bwijnen.net>
+     
+     Editor:   Andy Bierman
+               <mailto:andy@yumaworks.com>
+     
+     Editor:   Martin Bjorklund
+               <mailto:mbj@tail-f.com>";
+  description
+    "NETCONF Access Control Model.
+     
+     Copyright (c) 2012 IETF Trust and the persons identified as
+     authors of the code.  All rights reserved.
+     
+     Redistribution and use in source and binary forms, with or
+     without modification, is permitted pursuant to, and subject
+     to the license terms contained in, the Simplified BSD
+     License set forth in Section 4.c of the IETF Trust's
+     Legal Provisions Relating to IETF Documents
+     (http://trustee.ietf.org/license-info).
+     
+     This version of this YANG module is part of RFC 6536; see
+     the RFC itself for full legal notices.";
+
+  revision 2012-02-22 {
+    description
+      "Initial version";
+    reference
+      "RFC 6536: Network Configuration Protocol (NETCONF)
+                 Access Control Model";
+  }
+
+  extension default-deny-write {
+    description
+      "Used to indicate that the data model node
+       represents a sensitive security system parameter.
+       
+       If present, and the NACM module is enabled (i.e.,
+       /nacm/enable-nacm object equals 'true'), the NETCONF server
+       will only allow the designated 'recovery session' to have
+       write access to the node.  An explicit access control rule is
+       required for all other users.
+       
+       The 'default-deny-write' extension MAY appear within a data
+       definition statement.  It is ignored otherwise.";
+  }
+
+  extension default-deny-all {
+    description
+      "Used to indicate that the data model node
+       controls a very sensitive security system parameter.
+       
+       If present, and the NACM module is enabled (i.e.,
+       /nacm/enable-nacm object equals 'true'), the NETCONF server
+       will only allow the designated 'recovery session' to have
+       read, write, or execute access to the node.  An explicit
+       access control rule is required for all other users.
+       
+       The 'default-deny-all' extension MAY appear within a data
+       definition statement, 'rpc' statement, or 'notification'
+       statement.  It is ignored otherwise.";
+  }
+
+  typedef user-name-type {
+    type string {
+      length "1..max";
+    }
+    description
+      "General Purpose Username string.";
+  }
+
+  typedef matchall-string-type {
+    type string {
+      pattern "\\*";
+    }
+    description
+      "The string containing a single asterisk '*' is used
+       to conceptually represent all possible values
+       for the particular leaf using this data type.";
+  }
+
+  typedef access-operations-type {
+    type bits {
+      bit create {
+        description
+          "Any protocol operation that creates a
+           new data node.";
+      }
+      bit read {
+        description
+          "Any protocol operation or notification that
+           returns the value of a data node.";
+      }
+      bit update {
+        description
+          "Any protocol operation that alters an existing
+           data node.";
+      }
+      bit delete {
+        description
+          "Any protocol operation that removes a data node.";
+      }
+      bit exec {
+        description
+          "Execution access to the specified protocol operation.";
+      }
+    }
+    description
+      "NETCONF Access Operation.";
+  }
+
+  typedef group-name-type {
+    type string {
+      length "1..max";
+      pattern "[^\\*].*";
+    }
+    description
+      "Name of administrative group to which
+       users can be assigned.";
+  }
+
+  typedef action-type {
+    type enumeration {
+      enum "permit" {
+        description
+          "Requested action is permitted.";
+      }
+      enum "deny" {
+        description
+          "Requested action is denied.";
+      }
+    }
+    description
+      "Action taken by the server when a particular
+       rule matches.";
+  }
+
+  typedef node-instance-identifier {
+    type yang:xpath1.0;
+    description
+      "Path expression used to represent a special
+       data node instance identifier string.
+       
+       A node-instance-identifier value is an
+       unrestricted YANG instance-identifier expression.
+       All the same rules as an instance-identifier apply
+       except predicates for keys are optional.  If a key
+       predicate is missing, then the node-instance-identifier
+       represents all possible server instances for that key.
+       
+       This XPath expression is evaluated in the following context:
+       
+        o  The set of namespace declarations are those in scope on
+           the leaf element where this type is used.
+       
+        o  The set of variable bindings contains one variable,
+           'USER', which contains the name of the user of the current
+            session.
+       
+        o  The function library is the core function library, but
+           note that due to the syntax restrictions of an
+           instance-identifier, no functions are allowed.
+       
+        o  The context node is the root node in the data tree.";
+  }
+
+  container nacm {
+    nacm:default-deny-all;
+    description
+      "Parameters for NETCONF Access Control Model.";
+    leaf enable-nacm {
+      type boolean;
+      default "true";
+      description
+        "Enables or disables all NETCONF access control
+         enforcement.  If 'true', then enforcement
+         is enabled.  If 'false', then enforcement
+         is disabled.";
+    }
+    leaf read-default {
+      type action-type;
+      default "permit";
+      description
+        "Controls whether read access is granted if
+         no appropriate rule is found for a
+         particular read request.";
+    }
+    leaf write-default {
+      type action-type;
+      default "deny";
+      description
+        "Controls whether create, update, or delete access
+         is granted if no appropriate rule is found for a
+         particular write request.";
+    }
+    leaf exec-default {
+      type action-type;
+      default "permit";
+      description
+        "Controls whether exec access is granted if no appropriate
+         rule is found for a particular protocol operation request.";
+    }
+    leaf enable-external-groups {
+      type boolean;
+      default "true";
+      description
+        "Controls whether the server uses the groups reported by the
+         NETCONF transport layer when it assigns the user to a set of
+         NACM groups.  If this leaf has the value 'false', any group
+         names reported by the transport layer are ignored by the
+         server.";
+    }
+    leaf denied-operations {
+      type yang:zero-based-counter32;
+      config false;
+      mandatory true;
+      description
+        "Number of times since the server last restarted that a
+         protocol operation request was denied.";
+    }
+    leaf denied-data-writes {
+      type yang:zero-based-counter32;
+      config false;
+      mandatory true;
+      when "../denied-operations > 0";
+      description
+        "Number of times since the server last restarted that a
+         protocol operation request to alter
+         a configuration datastore was denied.";
+    }
+    leaf denied-notifications {
+      type yang:zero-based-counter32;
+      config false;
+      mandatory true;
+      description
+        "Number of times since the server last restarted that
+         a notification was dropped for a subscription because
+         access to the event type was denied.";
+    }
+    container groups {
+      description
+        "NETCONF Access Control Groups.";
+      list group {
+        key "name";
+        description
+          "One NACM Group Entry.  This list will only contain
+           configured entries, not any entries learned from
+           any transport protocols.";
+        leaf name {
+          type group-name-type;
+          description
+            "Group name associated with this entry.";
+        }
+        leaf-list user-name {
+          type user-name-type;
+          description
+            "Each entry identifies the username of
+             a member of the group associated with
+             this entry.";
+        }
+      }
+    }
+    list rule-list {
+      key "name";
+      ordered-by user;
+      description
+        "An ordered collection of access control rules.";
+      leaf name {
+        type string {
+          length "1..max";
+        }
+        description
+          "Arbitrary name assigned to the rule-list.";
+      }
+      leaf-list group {
+        type union {
+          type matchall-string-type;
+          type group-name-type;
+        }
+        description
+          "List of administrative groups that will be
+           assigned the associated access rights
+           defined by the 'rule' list.
+           
+           The string '*' indicates that all groups apply to the
+           entry.";
+      }
+      list rule {
+        key "name";
+        ordered-by user;
+        description
+          "One access control rule.
+           
+           Rules are processed in user-defined order until a match is
+           found.  A rule matches if 'module-name', 'rule-type', and
+           'access-operations' match the request.  If a rule
+           matches, the 'action' leaf determines if access is granted
+           or not.";
+        leaf name {
+          type string {
+            length "1..max";
+          }
+          description
+            "Arbitrary name assigned to the rule.";
+        }
+        leaf module-name {
+          type union {
+            type matchall-string-type;
+            type string;
+          }
+          default "*";
+          description
+            "Name of the module associated with this rule.
+             
+             This leaf matches if it has the value '*' or if the
+             object being accessed is defined in the module with the
+             specified module name.";
+        }
+        choice rule-type {
+          description
+            "This choice matches if all leafs present in the rule
+             match the request.  If no leafs are present, the
+             choice matches all requests.";
+          case protocol-operation {
+            leaf rpc-name {
+              type union {
+                type matchall-string-type;
+                type string;
+              }
+              description
+                "This leaf matches if it has the value '*' or if
+                 its value equals the requested protocol operation
+                 name.";
+            }
+          }
+          case notification {
+            leaf notification-name {
+              type union {
+                type matchall-string-type;
+                type string;
+              }
+              description
+                "This leaf matches if it has the value '*' or if its
+                 value equals the requested notification name.";
+            }
+          }
+          case data-node {
+            leaf path {
+              type node-instance-identifier;
+              mandatory true;
+              description
+                "Data Node Instance Identifier associated with the
+                 data node controlled by this rule.
+                 
+                 Configuration data or state data instance
+                 identifiers start with a top-level data node.  A
+                 complete instance identifier is required for this
+                 type of path value.
+                 
+                 The special value '/' refers to all possible
+                 datastore contents.";
+            }
+          }
+        }
+        leaf access-operations {
+          type union {
+            type matchall-string-type;
+            type access-operations-type;
+          }
+          default "*";
+          description
+            "Access operations associated with this rule.
+             
+             This leaf matches if it has the value '*' or if the
+             bit corresponding to the requested operation is set.";
+        }
+        leaf action {
+          type action-type;
+          mandatory true;
+          description
+            "The access control action associated with the
+             rule.  If a rule is determined to match a
+             particular request, then this object is used
+             to determine whether to permit or deny the
+             request.";
+        }
+        leaf comment {
+          type string;
+          description
+            "A textual description of the access rule.";
+        }
+      }
+    }
+  }
+}
diff --git a/tools/lint/examples/ietf-netconf-acm-when.yin b/tools/lint/examples/ietf-netconf-acm-when.yin
new file mode 100644
index 0000000..cbff758
--- /dev/null
+++ b/tools/lint/examples/ietf-netconf-acm-when.yin
@@ -0,0 +1,447 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module xmlns="urn:ietf:params:xml:ns:yang:yin:1" xmlns:nacm="urn:ietf:params:xml:ns:yang:ietf-netconf-acm" xmlns:yang="urn:ietf:params:xml:ns:yang:ietf-yang-types" name="ietf-netconf-acm-when">
+  <namespace uri="urn:ietf:params:xml:ns:yang:ietf-netconf-acm"/>
+  <prefix value="nacm"/>
+  <import module="ietf-yang-types">
+    <prefix value="yang"/>
+  </import>
+  <organization>
+    <text>IETF NETCONF (Network Configuration) Working Group</text>
+  </organization>
+  <contact>
+    <text>WG Web:   &lt;http://tools.ietf.org/wg/netconf/&gt;
+WG List:  &lt;mailto:netconf@ietf.org&gt;
+
+WG Chair: Mehmet Ersue
+          &lt;mailto:mehmet.ersue@nsn.com&gt;
+
+WG Chair: Bert Wijnen
+          &lt;mailto:bertietf@bwijnen.net&gt;
+
+Editor:   Andy Bierman
+          &lt;mailto:andy@yumaworks.com&gt;
+
+Editor:   Martin Bjorklund
+          &lt;mailto:mbj@tail-f.com&gt;</text>
+  </contact>
+  <description>
+    <text>NETCONF Access Control Model.
+
+Copyright (c) 2012 IETF Trust and the persons identified as
+authors of the code.  All rights reserved.
+
+Redistribution and use in source and binary forms, with or
+without modification, is permitted pursuant to, and subject
+to the license terms contained in, the Simplified BSD
+License set forth in Section 4.c of the IETF Trust's
+Legal Provisions Relating to IETF Documents
+(http://trustee.ietf.org/license-info).
+
+This version of this YANG module is part of RFC 6536; see
+the RFC itself for full legal notices.</text>
+  </description>
+  <revision date="2012-02-22">
+    <description>
+      <text>Initial version</text>
+    </description>
+    <reference>
+      <text>RFC 6536: Network Configuration Protocol (NETCONF)
+          Access Control Model</text>
+    </reference>
+  </revision>
+  <extension name="default-deny-write">
+    <description>
+      <text>Used to indicate that the data model node
+represents a sensitive security system parameter.
+
+If present, and the NACM module is enabled (i.e.,
+/nacm/enable-nacm object equals 'true'), the NETCONF server
+will only allow the designated 'recovery session' to have
+write access to the node.  An explicit access control rule is
+required for all other users.
+
+The 'default-deny-write' extension MAY appear within a data
+definition statement.  It is ignored otherwise.</text>
+    </description>
+  </extension>
+  <extension name="default-deny-all">
+    <description>
+      <text>Used to indicate that the data model node
+controls a very sensitive security system parameter.
+
+If present, and the NACM module is enabled (i.e.,
+/nacm/enable-nacm object equals 'true'), the NETCONF server
+will only allow the designated 'recovery session' to have
+read, write, or execute access to the node.  An explicit
+access control rule is required for all other users.
+
+The 'default-deny-all' extension MAY appear within a data
+definition statement, 'rpc' statement, or 'notification'
+statement.  It is ignored otherwise.</text>
+    </description>
+  </extension>
+  <typedef name="user-name-type">
+    <type name="string">
+      <length value="1..max"/>
+    </type>
+    <description>
+      <text>General Purpose Username string.</text>
+    </description>
+  </typedef>
+  <typedef name="matchall-string-type">
+    <type name="string">
+      <pattern value="\*"/>
+    </type>
+    <description>
+      <text>The string containing a single asterisk '*' is used
+to conceptually represent all possible values
+for the particular leaf using this data type.</text>
+    </description>
+  </typedef>
+  <typedef name="access-operations-type">
+    <type name="bits">
+      <bit name="create">
+        <description>
+          <text>Any protocol operation that creates a
+new data node.</text>
+        </description>
+      </bit>
+      <bit name="read">
+        <description>
+          <text>Any protocol operation or notification that
+returns the value of a data node.</text>
+        </description>
+      </bit>
+      <bit name="update">
+        <description>
+          <text>Any protocol operation that alters an existing
+data node.</text>
+        </description>
+      </bit>
+      <bit name="delete">
+        <description>
+          <text>Any protocol operation that removes a data node.</text>
+        </description>
+      </bit>
+      <bit name="exec">
+        <description>
+          <text>Execution access to the specified protocol operation.</text>
+        </description>
+      </bit>
+    </type>
+    <description>
+      <text>NETCONF Access Operation.</text>
+    </description>
+  </typedef>
+  <typedef name="group-name-type">
+    <type name="string">
+      <length value="1..max"/>
+      <pattern value="[^\*].*"/>
+    </type>
+    <description>
+      <text>Name of administrative group to which
+users can be assigned.</text>
+    </description>
+  </typedef>
+  <typedef name="action-type">
+    <type name="enumeration">
+      <enum name="permit">
+        <description>
+          <text>Requested action is permitted.</text>
+        </description>
+      </enum>
+      <enum name="deny">
+        <description>
+          <text>Requested action is denied.</text>
+        </description>
+      </enum>
+    </type>
+    <description>
+      <text>Action taken by the server when a particular
+rule matches.</text>
+    </description>
+  </typedef>
+  <typedef name="node-instance-identifier">
+    <type name="yang:xpath1.0"/>
+    <description>
+      <text>Path expression used to represent a special
+data node instance identifier string.
+
+A node-instance-identifier value is an
+unrestricted YANG instance-identifier expression.
+All the same rules as an instance-identifier apply
+except predicates for keys are optional.  If a key
+predicate is missing, then the node-instance-identifier
+represents all possible server instances for that key.
+
+This XPath expression is evaluated in the following context:
+
+ o  The set of namespace declarations are those in scope on
+    the leaf element where this type is used.
+
+ o  The set of variable bindings contains one variable,
+    'USER', which contains the name of the user of the current
+     session.
+
+ o  The function library is the core function library, but
+    note that due to the syntax restrictions of an
+    instance-identifier, no functions are allowed.
+
+ o  The context node is the root node in the data tree.</text>
+    </description>
+  </typedef>
+  <container name="nacm">
+    <nacm:default-deny-all/>
+    <description>
+      <text>Parameters for NETCONF Access Control Model.</text>
+    </description>
+    <leaf name="enable-nacm">
+      <type name="boolean"/>
+      <default value="true"/>
+      <description>
+        <text>Enables or disables all NETCONF access control
+enforcement.  If 'true', then enforcement
+is enabled.  If 'false', then enforcement
+is disabled.</text>
+      </description>
+    </leaf>
+    <leaf name="read-default">
+      <type name="action-type"/>
+      <default value="permit"/>
+      <description>
+        <text>Controls whether read access is granted if
+no appropriate rule is found for a
+particular read request.</text>
+      </description>
+    </leaf>
+    <leaf name="write-default">
+      <type name="action-type"/>
+      <default value="deny"/>
+      <description>
+        <text>Controls whether create, update, or delete access
+is granted if no appropriate rule is found for a
+particular write request.</text>
+      </description>
+    </leaf>
+    <leaf name="exec-default">
+      <type name="action-type"/>
+      <default value="permit"/>
+      <description>
+        <text>Controls whether exec access is granted if no appropriate
+rule is found for a particular protocol operation request.</text>
+      </description>
+    </leaf>
+    <leaf name="enable-external-groups">
+      <type name="boolean"/>
+      <default value="true"/>
+      <description>
+        <text>Controls whether the server uses the groups reported by the
+NETCONF transport layer when it assigns the user to a set of
+NACM groups.  If this leaf has the value 'false', any group
+names reported by the transport layer are ignored by the
+server.</text>
+      </description>
+    </leaf>
+    <leaf name="denied-operations">
+      <type name="yang:zero-based-counter32"/>
+      <config value="false"/>
+      <mandatory value="true"/>
+      <description>
+        <text>Number of times since the server last restarted that a
+protocol operation request was denied.</text>
+      </description>
+    </leaf>
+    <leaf name="denied-data-writes">
+      <type name="yang:zero-based-counter32"/>
+      <config value="false"/>
+      <mandatory value="true"/>
+      <when value="../denied-operations > 0"/>
+      <description>
+        <text>Number of times since the server last restarted that a
+protocol operation request to alter
+a configuration datastore was denied.</text>
+      </description>
+    </leaf>
+    <leaf name="denied-notifications">
+      <type name="yang:zero-based-counter32"/>
+      <config value="false"/>
+      <mandatory value="true"/>
+      <description>
+        <text>Number of times since the server last restarted that
+a notification was dropped for a subscription because
+access to the event type was denied.</text>
+      </description>
+    </leaf>
+    <container name="groups">
+      <description>
+        <text>NETCONF Access Control Groups.</text>
+      </description>
+      <list name="group">
+        <key value="name"/>
+        <description>
+          <text>One NACM Group Entry.  This list will only contain
+configured entries, not any entries learned from
+any transport protocols.</text>
+        </description>
+        <leaf name="name">
+          <type name="group-name-type"/>
+          <description>
+            <text>Group name associated with this entry.</text>
+          </description>
+        </leaf>
+        <leaf-list name="user-name">
+          <type name="user-name-type"/>
+          <description>
+            <text>Each entry identifies the username of
+a member of the group associated with
+this entry.</text>
+          </description>
+        </leaf-list>
+      </list>
+    </container>
+    <list name="rule-list">
+      <key value="name"/>
+      <ordered-by value="user"/>
+      <description>
+        <text>An ordered collection of access control rules.</text>
+      </description>
+      <leaf name="name">
+        <type name="string">
+          <length value="1..max"/>
+        </type>
+        <description>
+          <text>Arbitrary name assigned to the rule-list.</text>
+        </description>
+      </leaf>
+      <leaf-list name="group">
+        <type name="union">
+          <type name="matchall-string-type"/>
+          <type name="group-name-type"/>
+        </type>
+        <description>
+          <text>List of administrative groups that will be
+assigned the associated access rights
+defined by the 'rule' list.
+
+The string '*' indicates that all groups apply to the
+entry.</text>
+        </description>
+      </leaf-list>
+      <list name="rule">
+        <key value="name"/>
+        <ordered-by value="user"/>
+        <description>
+          <text>One access control rule.
+
+Rules are processed in user-defined order until a match is
+found.  A rule matches if 'module-name', 'rule-type', and
+'access-operations' match the request.  If a rule
+matches, the 'action' leaf determines if access is granted
+or not.</text>
+        </description>
+        <leaf name="name">
+          <type name="string">
+            <length value="1..max"/>
+          </type>
+          <description>
+            <text>Arbitrary name assigned to the rule.</text>
+          </description>
+        </leaf>
+        <leaf name="module-name">
+          <type name="union">
+            <type name="matchall-string-type"/>
+            <type name="string"/>
+          </type>
+          <default value="*"/>
+          <description>
+            <text>Name of the module associated with this rule.
+
+This leaf matches if it has the value '*' or if the
+object being accessed is defined in the module with the
+specified module name.</text>
+          </description>
+        </leaf>
+        <choice name="rule-type">
+          <description>
+            <text>This choice matches if all leafs present in the rule
+match the request.  If no leafs are present, the
+choice matches all requests.</text>
+          </description>
+          <case name="protocol-operation">
+            <leaf name="rpc-name">
+              <type name="union">
+                <type name="matchall-string-type"/>
+                <type name="string"/>
+              </type>
+              <description>
+                <text>This leaf matches if it has the value '*' or if
+its value equals the requested protocol operation
+name.</text>
+              </description>
+            </leaf>
+          </case>
+          <case name="notification">
+            <leaf name="notification-name">
+              <type name="union">
+                <type name="matchall-string-type"/>
+                <type name="string"/>
+              </type>
+              <description>
+                <text>This leaf matches if it has the value '*' or if its
+value equals the requested notification name.</text>
+              </description>
+            </leaf>
+          </case>
+          <case name="data-node">
+            <leaf name="path">
+              <type name="node-instance-identifier"/>
+              <mandatory value="true"/>
+              <description>
+                <text>Data Node Instance Identifier associated with the
+data node controlled by this rule.
+
+Configuration data or state data instance
+identifiers start with a top-level data node.  A
+complete instance identifier is required for this
+type of path value.
+
+The special value '/' refers to all possible
+datastore contents.</text>
+              </description>
+            </leaf>
+          </case>
+        </choice>
+        <leaf name="access-operations">
+          <type name="union">
+            <type name="matchall-string-type"/>
+            <type name="access-operations-type"/>
+          </type>
+          <default value="*"/>
+          <description>
+            <text>Access operations associated with this rule.
+
+This leaf matches if it has the value '*' or if the
+bit corresponding to the requested operation is set.</text>
+          </description>
+        </leaf>
+        <leaf name="action">
+          <type name="action-type"/>
+          <mandatory value="true"/>
+          <description>
+            <text>The access control action associated with the
+rule.  If a rule is determined to match a
+particular request, then this object is used
+to determine whether to permit or deny the
+request.</text>
+          </description>
+        </leaf>
+        <leaf name="comment">
+          <type name="string"/>
+          <description>
+            <text>A textual description of the access rule.</text>
+          </description>
+        </leaf>
+      </list>
+    </list>
+  </container>
+</module>
diff --git a/tools/lint/examples/ietf-netconf-acm-when2.yin b/tools/lint/examples/ietf-netconf-acm-when2.yin
new file mode 100644
index 0000000..f8f25a0
--- /dev/null
+++ b/tools/lint/examples/ietf-netconf-acm-when2.yin
@@ -0,0 +1,447 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module xmlns="urn:ietf:params:xml:ns:yang:yin:1" xmlns:nacm="urn:ietf:params:xml:ns:yang:ietf-netconf-acm" xmlns:yang="urn:ietf:params:xml:ns:yang:ietf-yang-types" name="ietf-netconf-acm-when2">
+  <namespace uri="urn:ietf:params:xml:ns:yang:ietf-netconf-acm"/>
+  <prefix value="nacm"/>
+  <import module="ietf-yang-types">
+    <prefix value="yang"/>
+  </import>
+  <organization>
+    <text>IETF NETCONF (Network Configuration) Working Group</text>
+  </organization>
+  <contact>
+    <text>WG Web:   &lt;http://tools.ietf.org/wg/netconf/&gt;
+WG List:  &lt;mailto:netconf@ietf.org&gt;
+
+WG Chair: Mehmet Ersue
+          &lt;mailto:mehmet.ersue@nsn.com&gt;
+
+WG Chair: Bert Wijnen
+          &lt;mailto:bertietf@bwijnen.net&gt;
+
+Editor:   Andy Bierman
+          &lt;mailto:andy@yumaworks.com&gt;
+
+Editor:   Martin Bjorklund
+          &lt;mailto:mbj@tail-f.com&gt;</text>
+  </contact>
+  <description>
+    <text>NETCONF Access Control Model.
+
+Copyright (c) 2012 IETF Trust and the persons identified as
+authors of the code.  All rights reserved.
+
+Redistribution and use in source and binary forms, with or
+without modification, is permitted pursuant to, and subject
+to the license terms contained in, the Simplified BSD
+License set forth in Section 4.c of the IETF Trust's
+Legal Provisions Relating to IETF Documents
+(http://trustee.ietf.org/license-info).
+
+This version of this YANG module is part of RFC 6536; see
+the RFC itself for full legal notices.</text>
+  </description>
+  <revision date="2012-02-22">
+    <description>
+      <text>Initial version</text>
+    </description>
+    <reference>
+      <text>RFC 6536: Network Configuration Protocol (NETCONF)
+          Access Control Model</text>
+    </reference>
+  </revision>
+  <extension name="default-deny-write">
+    <description>
+      <text>Used to indicate that the data model node
+represents a sensitive security system parameter.
+
+If present, and the NACM module is enabled (i.e.,
+/nacm/enable-nacm object equals 'true'), the NETCONF server
+will only allow the designated 'recovery session' to have
+write access to the node.  An explicit access control rule is
+required for all other users.
+
+The 'default-deny-write' extension MAY appear within a data
+definition statement.  It is ignored otherwise.</text>
+    </description>
+  </extension>
+  <extension name="default-deny-all">
+    <description>
+      <text>Used to indicate that the data model node
+controls a very sensitive security system parameter.
+
+If present, and the NACM module is enabled (i.e.,
+/nacm/enable-nacm object equals 'true'), the NETCONF server
+will only allow the designated 'recovery session' to have
+read, write, or execute access to the node.  An explicit
+access control rule is required for all other users.
+
+The 'default-deny-all' extension MAY appear within a data
+definition statement, 'rpc' statement, or 'notification'
+statement.  It is ignored otherwise.</text>
+    </description>
+  </extension>
+  <typedef name="user-name-type">
+    <type name="string">
+      <length value="1..max"/>
+    </type>
+    <description>
+      <text>General Purpose Username string.</text>
+    </description>
+  </typedef>
+  <typedef name="matchall-string-type">
+    <type name="string">
+      <pattern value="\*"/>
+    </type>
+    <description>
+      <text>The string containing a single asterisk '*' is used
+to conceptually represent all possible values
+for the particular leaf using this data type.</text>
+    </description>
+  </typedef>
+  <typedef name="access-operations-type">
+    <type name="bits">
+      <bit name="create">
+        <description>
+          <text>Any protocol operation that creates a
+new data node.</text>
+        </description>
+      </bit>
+      <bit name="read">
+        <description>
+          <text>Any protocol operation or notification that
+returns the value of a data node.</text>
+        </description>
+      </bit>
+      <bit name="update">
+        <description>
+          <text>Any protocol operation that alters an existing
+data node.</text>
+        </description>
+      </bit>
+      <bit name="delete">
+        <description>
+          <text>Any protocol operation that removes a data node.</text>
+        </description>
+      </bit>
+      <bit name="exec">
+        <description>
+          <text>Execution access to the specified protocol operation.</text>
+        </description>
+      </bit>
+    </type>
+    <description>
+      <text>NETCONF Access Operation.</text>
+    </description>
+  </typedef>
+  <typedef name="group-name-type">
+    <type name="string">
+      <length value="1..max"/>
+      <pattern value="[^\*].*"/>
+    </type>
+    <description>
+      <text>Name of administrative group to which
+users can be assigned.</text>
+    </description>
+  </typedef>
+  <typedef name="action-type">
+    <type name="enumeration">
+      <enum name="permit">
+        <description>
+          <text>Requested action is permitted.</text>
+        </description>
+      </enum>
+      <enum name="deny">
+        <description>
+          <text>Requested action is denied.</text>
+        </description>
+      </enum>
+    </type>
+    <description>
+      <text>Action taken by the server when a particular
+rule matches.</text>
+    </description>
+  </typedef>
+  <typedef name="node-instance-identifier">
+    <type name="yang:xpath1.0"/>
+    <description>
+      <text>Path expression used to represent a special
+data node instance identifier string.
+
+A node-instance-identifier value is an
+unrestricted YANG instance-identifier expression.
+All the same rules as an instance-identifier apply
+except predicates for keys are optional.  If a key
+predicate is missing, then the node-instance-identifier
+represents all possible server instances for that key.
+
+This XPath expression is evaluated in the following context:
+
+ o  The set of namespace declarations are those in scope on
+    the leaf element where this type is used.
+
+ o  The set of variable bindings contains one variable,
+    'USER', which contains the name of the user of the current
+     session.
+
+ o  The function library is the core function library, but
+    note that due to the syntax restrictions of an
+    instance-identifier, no functions are allowed.
+
+ o  The context node is the root node in the data tree.</text>
+    </description>
+  </typedef>
+  <container name="nacm">
+    <nacm:default-deny-all/>
+    <description>
+      <text>Parameters for NETCONF Access Control Model.</text>
+    </description>
+    <leaf name="enable-nacm">
+      <type name="boolean"/>
+      <default value="true"/>
+      <description>
+        <text>Enables or disables all NETCONF access control
+enforcement.  If 'true', then enforcement
+is enabled.  If 'false', then enforcement
+is disabled.</text>
+      </description>
+    </leaf>
+    <leaf name="read-default">
+      <type name="action-type"/>
+      <default value="permit"/>
+      <description>
+        <text>Controls whether read access is granted if
+no appropriate rule is found for a
+particular read request.</text>
+      </description>
+    </leaf>
+    <leaf name="write-default">
+      <type name="action-type"/>
+      <default value="deny"/>
+      <description>
+        <text>Controls whether create, update, or delete access
+is granted if no appropriate rule is found for a
+particular write request.</text>
+      </description>
+    </leaf>
+    <leaf name="exec-default">
+      <type name="action-type"/>
+      <default value="permit"/>
+      <description>
+        <text>Controls whether exec access is granted if no appropriate
+rule is found for a particular protocol operation request.</text>
+      </description>
+    </leaf>
+    <leaf name="enable-external-groups">
+      <type name="boolean"/>
+      <default value="true"/>
+      <description>
+        <text>Controls whether the server uses the groups reported by the
+NETCONF transport layer when it assigns the user to a set of
+NACM groups.  If this leaf has the value 'false', any group
+names reported by the transport layer are ignored by the
+server.</text>
+      </description>
+    </leaf>
+    <leaf name="denied-operations">
+      <type name="yang:zero-based-counter32"/>
+      <config value="false"/>
+      <mandatory value="true"/>
+      <description>
+        <text>Number of times since the server last restarted that a
+protocol operation request was denied.</text>
+      </description>
+    </leaf>
+    <leaf name="denied-data-writes">
+      <type name="yang:zero-based-counter32"/>
+      <config value="false"/>
+      <mandatory value="true"/>
+      <when condition="../denied-operations > 0"/>
+      <description>
+        <text>Number of times since the server last restarted that a
+protocol operation request to alter
+a configuration datastore was denied.</text>
+      </description>
+    </leaf>
+    <leaf name="denied-notifications">
+      <type name="yang:zero-based-counter32"/>
+      <config value="false"/>
+      <mandatory value="true"/>
+      <description>
+        <text>Number of times since the server last restarted that
+a notification was dropped for a subscription because
+access to the event type was denied.</text>
+      </description>
+    </leaf>
+    <container name="groups">
+      <description>
+        <text>NETCONF Access Control Groups.</text>
+      </description>
+      <list name="group">
+        <key value="name"/>
+        <description>
+          <text>One NACM Group Entry.  This list will only contain
+configured entries, not any entries learned from
+any transport protocols.</text>
+        </description>
+        <leaf name="name">
+          <type name="group-name-type"/>
+          <description>
+            <text>Group name associated with this entry.</text>
+          </description>
+        </leaf>
+        <leaf-list name="user-name">
+          <type name="user-name-type"/>
+          <description>
+            <text>Each entry identifies the username of
+a member of the group associated with
+this entry.</text>
+          </description>
+        </leaf-list>
+      </list>
+    </container>
+    <list name="rule-list">
+      <key value="name"/>
+      <ordered-by value="user"/>
+      <description>
+        <text>An ordered collection of access control rules.</text>
+      </description>
+      <leaf name="name">
+        <type name="string">
+          <length value="1..max"/>
+        </type>
+        <description>
+          <text>Arbitrary name assigned to the rule-list.</text>
+        </description>
+      </leaf>
+      <leaf-list name="group">
+        <type name="union">
+          <type name="matchall-string-type"/>
+          <type name="group-name-type"/>
+        </type>
+        <description>
+          <text>List of administrative groups that will be
+assigned the associated access rights
+defined by the 'rule' list.
+
+The string '*' indicates that all groups apply to the
+entry.</text>
+        </description>
+      </leaf-list>
+      <list name="rule">
+        <key value="name"/>
+        <ordered-by value="user"/>
+        <description>
+          <text>One access control rule.
+
+Rules are processed in user-defined order until a match is
+found.  A rule matches if 'module-name', 'rule-type', and
+'access-operations' match the request.  If a rule
+matches, the 'action' leaf determines if access is granted
+or not.</text>
+        </description>
+        <leaf name="name">
+          <type name="string">
+            <length value="1..max"/>
+          </type>
+          <description>
+            <text>Arbitrary name assigned to the rule.</text>
+          </description>
+        </leaf>
+        <leaf name="module-name">
+          <type name="union">
+            <type name="matchall-string-type"/>
+            <type name="string"/>
+          </type>
+          <default value="*"/>
+          <description>
+            <text>Name of the module associated with this rule.
+
+This leaf matches if it has the value '*' or if the
+object being accessed is defined in the module with the
+specified module name.</text>
+          </description>
+        </leaf>
+        <choice name="rule-type">
+          <description>
+            <text>This choice matches if all leafs present in the rule
+match the request.  If no leafs are present, the
+choice matches all requests.</text>
+          </description>
+          <case name="protocol-operation">
+            <leaf name="rpc-name">
+              <type name="union">
+                <type name="matchall-string-type"/>
+                <type name="string"/>
+              </type>
+              <description>
+                <text>This leaf matches if it has the value '*' or if
+its value equals the requested protocol operation
+name.</text>
+              </description>
+            </leaf>
+          </case>
+          <case name="notification">
+            <leaf name="notification-name">
+              <type name="union">
+                <type name="matchall-string-type"/>
+                <type name="string"/>
+              </type>
+              <description>
+                <text>This leaf matches if it has the value '*' or if its
+value equals the requested notification name.</text>
+              </description>
+            </leaf>
+          </case>
+          <case name="data-node">
+            <leaf name="path">
+              <type name="node-instance-identifier"/>
+              <mandatory value="true"/>
+              <description>
+                <text>Data Node Instance Identifier associated with the
+data node controlled by this rule.
+
+Configuration data or state data instance
+identifiers start with a top-level data node.  A
+complete instance identifier is required for this
+type of path value.
+
+The special value '/' refers to all possible
+datastore contents.</text>
+              </description>
+            </leaf>
+          </case>
+        </choice>
+        <leaf name="access-operations">
+          <type name="union">
+            <type name="matchall-string-type"/>
+            <type name="access-operations-type"/>
+          </type>
+          <default value="*"/>
+          <description>
+            <text>Access operations associated with this rule.
+
+This leaf matches if it has the value '*' or if the
+bit corresponding to the requested operation is set.</text>
+          </description>
+        </leaf>
+        <leaf name="action">
+          <type name="action-type"/>
+          <mandatory value="true"/>
+          <description>
+            <text>The access control action associated with the
+rule.  If a rule is determined to match a
+particular request, then this object is used
+to determine whether to permit or deny the
+request.</text>
+          </description>
+        </leaf>
+        <leaf name="comment">
+          <type name="string"/>
+          <description>
+            <text>A textual description of the access rule.</text>
+          </description>
+        </leaf>
+      </list>
+    </list>
+  </container>
+</module>
diff --git a/tools/lint/examples/ietf-netconf-acm.yang b/tools/lint/examples/ietf-netconf-acm.yang
new file mode 100644
index 0000000..dc3655e
--- /dev/null
+++ b/tools/lint/examples/ietf-netconf-acm.yang
@@ -0,0 +1,411 @@
+module ietf-netconf-acm {
+  namespace "urn:ietf:params:xml:ns:yang:ietf-netconf-acm";
+  prefix nacm;
+
+  import ietf-yang-types {
+    prefix yang;
+  }
+
+  organization
+    "IETF NETCONF (Network Configuration) Working Group";
+  contact
+    "WG Web:   <http://tools.ietf.org/wg/netconf/>
+     WG List:  <mailto:netconf@ietf.org>
+     
+     WG Chair: Mehmet Ersue
+               <mailto:mehmet.ersue@nsn.com>
+     
+     WG Chair: Bert Wijnen
+               <mailto:bertietf@bwijnen.net>
+     
+     Editor:   Andy Bierman
+               <mailto:andy@yumaworks.com>
+     
+     Editor:   Martin Bjorklund
+               <mailto:mbj@tail-f.com>";
+  description
+    "NETCONF Access Control Model.
+     
+     Copyright (c) 2012 IETF Trust and the persons identified as
+     authors of the code.  All rights reserved.
+     
+     Redistribution and use in source and binary forms, with or
+     without modification, is permitted pursuant to, and subject
+     to the license terms contained in, the Simplified BSD
+     License set forth in Section 4.c of the IETF Trust's
+     Legal Provisions Relating to IETF Documents
+     (http://trustee.ietf.org/license-info).
+     
+     This version of this YANG module is part of RFC 6536; see
+     the RFC itself for full legal notices.";
+
+  revision 2012-02-22 {
+    description
+      "Initial version";
+    reference
+      "RFC 6536: Network Configuration Protocol (NETCONF)
+                 Access Control Model";
+  }
+
+  extension default-deny-write {
+    description
+      "Used to indicate that the data model node
+       represents a sensitive security system parameter.
+       
+       If present, and the NACM module is enabled (i.e.,
+       /nacm/enable-nacm object equals 'true'), the NETCONF server
+       will only allow the designated 'recovery session' to have
+       write access to the node.  An explicit access control rule is
+       required for all other users.
+       
+       The 'default-deny-write' extension MAY appear within a data
+       definition statement.  It is ignored otherwise.";
+  }
+
+  extension default-deny-all {
+    description
+      "Used to indicate that the data model node
+       controls a very sensitive security system parameter.
+       
+       If present, and the NACM module is enabled (i.e.,
+       /nacm/enable-nacm object equals 'true'), the NETCONF server
+       will only allow the designated 'recovery session' to have
+       read, write, or execute access to the node.  An explicit
+       access control rule is required for all other users.
+       
+       The 'default-deny-all' extension MAY appear within a data
+       definition statement, 'rpc' statement, or 'notification'
+       statement.  It is ignored otherwise.";
+  }
+
+  typedef user-name-type {
+    type string {
+      length "1..max";
+    }
+    description
+      "General Purpose Username string.";
+  }
+
+  typedef matchall-string-type {
+    type string {
+      pattern "\\*";
+    }
+    description
+      "The string containing a single asterisk '*' is used
+       to conceptually represent all possible values
+       for the particular leaf using this data type.";
+  }
+
+  typedef access-operations-type {
+    type bits {
+      bit create {
+        description
+          "Any protocol operation that creates a
+           new data node.";
+      }
+      bit read {
+        description
+          "Any protocol operation or notification that
+           returns the value of a data node.";
+      }
+      bit update {
+        description
+          "Any protocol operation that alters an existing
+           data node.";
+      }
+      bit delete {
+        description
+          "Any protocol operation that removes a data node.";
+      }
+      bit exec {
+        description
+          "Execution access to the specified protocol operation.";
+      }
+    }
+    description
+      "NETCONF Access Operation.";
+  }
+
+  typedef group-name-type {
+    type string {
+      length "1..max";
+      pattern "[^\\*].*";
+    }
+    description
+      "Name of administrative group to which
+       users can be assigned.";
+  }
+
+  typedef action-type {
+    type enumeration {
+      enum "permit" {
+        description
+          "Requested action is permitted.";
+      }
+      enum "deny" {
+        description
+          "Requested action is denied.";
+      }
+    }
+    description
+      "Action taken by the server when a particular
+       rule matches.";
+  }
+
+  typedef node-instance-identifier {
+    type yang:xpath1.0;
+    description
+      "Path expression used to represent a special
+       data node instance identifier string.
+       
+       A node-instance-identifier value is an
+       unrestricted YANG instance-identifier expression.
+       All the same rules as an instance-identifier apply
+       except predicates for keys are optional.  If a key
+       predicate is missing, then the node-instance-identifier
+       represents all possible server instances for that key.
+       
+       This XPath expression is evaluated in the following context:
+       
+        o  The set of namespace declarations are those in scope on
+           the leaf element where this type is used.
+       
+        o  The set of variable bindings contains one variable,
+           'USER', which contains the name of the user of the current
+            session.
+       
+        o  The function library is the core function library, but
+           note that due to the syntax restrictions of an
+           instance-identifier, no functions are allowed.
+       
+        o  The context node is the root node in the data tree.";
+  }
+
+  container nacm {
+    nacm:default-deny-all;
+    description
+      "Parameters for NETCONF Access Control Model.";
+    leaf enable-nacm {
+      type boolean;
+      default "true";
+      description
+        "Enables or disables all NETCONF access control
+         enforcement.  If 'true', then enforcement
+         is enabled.  If 'false', then enforcement
+         is disabled.";
+    }
+    leaf read-default {
+      type action-type;
+      default "permit";
+      description
+        "Controls whether read access is granted if
+         no appropriate rule is found for a
+         particular read request.";
+    }
+    leaf write-default {
+      type action-type;
+      default "deny";
+      description
+        "Controls whether create, update, or delete access
+         is granted if no appropriate rule is found for a
+         particular write request.";
+    }
+    leaf exec-default {
+      type action-type;
+      default "permit";
+      description
+        "Controls whether exec access is granted if no appropriate
+         rule is found for a particular protocol operation request.";
+    }
+    leaf enable-external-groups {
+      type boolean;
+      default "true";
+      description
+        "Controls whether the server uses the groups reported by the
+         NETCONF transport layer when it assigns the user to a set of
+         NACM groups.  If this leaf has the value 'false', any group
+         names reported by the transport layer are ignored by the
+         server.";
+    }
+    leaf denied-operations {
+      type yang:zero-based-counter32;
+      config false;
+      mandatory true;
+      description
+        "Number of times since the server last restarted that a
+         protocol operation request was denied.";
+    }
+    leaf denied-data-writes {
+      type yang:zero-based-counter32;
+      config false;
+      mandatory true;
+      description
+        "Number of times since the server last restarted that a
+         protocol operation request to alter
+         a configuration datastore was denied.";
+    }
+    leaf denied-notifications {
+      type yang:zero-based-counter32;
+      config false;
+      mandatory true;
+      description
+        "Number of times since the server last restarted that
+         a notification was dropped for a subscription because
+         access to the event type was denied.";
+    }
+    container groups {
+      description
+        "NETCONF Access Control Groups.";
+      list group {
+        key "name";
+        description
+          "One NACM Group Entry.  This list will only contain
+           configured entries, not any entries learned from
+           any transport protocols.";
+        leaf name {
+          type group-name-type;
+          description
+            "Group name associated with this entry.";
+        }
+        leaf-list user-name {
+          type user-name-type;
+          description
+            "Each entry identifies the username of
+             a member of the group associated with
+             this entry.";
+        }
+      }
+    }
+    list rule-list {
+      key "name";
+      ordered-by user;
+      description
+        "An ordered collection of access control rules.";
+      leaf name {
+        type string {
+          length "1..max";
+        }
+        description
+          "Arbitrary name assigned to the rule-list.";
+      }
+      leaf-list group {
+        type union {
+          type matchall-string-type;
+          type group-name-type;
+        }
+        description
+          "List of administrative groups that will be
+           assigned the associated access rights
+           defined by the 'rule' list.
+           
+           The string '*' indicates that all groups apply to the
+           entry.";
+      }
+      list rule {
+        key "name";
+        ordered-by user;
+        description
+          "One access control rule.
+           
+           Rules are processed in user-defined order until a match is
+           found.  A rule matches if 'module-name', 'rule-type', and
+           'access-operations' match the request.  If a rule
+           matches, the 'action' leaf determines if access is granted
+           or not.";
+        leaf name {
+          type string {
+            length "1..max";
+          }
+          description
+            "Arbitrary name assigned to the rule.";
+        }
+        leaf module-name {
+          type union {
+            type matchall-string-type;
+            type string;
+          }
+          default "*";
+          description
+            "Name of the module associated with this rule.
+             
+             This leaf matches if it has the value '*' or if the
+             object being accessed is defined in the module with the
+             specified module name.";
+        }
+        choice rule-type {
+          description
+            "This choice matches if all leafs present in the rule
+             match the request.  If no leafs are present, the
+             choice matches all requests.";
+          case protocol-operation {
+            leaf rpc-name {
+              type union {
+                type matchall-string-type;
+                type string;
+              }
+              description
+                "This leaf matches if it has the value '*' or if
+                 its value equals the requested protocol operation
+                 name.";
+            }
+          }
+          case notification {
+            leaf notification-name {
+              type union {
+                type matchall-string-type;
+                type string;
+              }
+              description
+                "This leaf matches if it has the value '*' or if its
+                 value equals the requested notification name.";
+            }
+          }
+          case data-node {
+            leaf path {
+              type node-instance-identifier;
+              mandatory true;
+              description
+                "Data Node Instance Identifier associated with the
+                 data node controlled by this rule.
+                 
+                 Configuration data or state data instance
+                 identifiers start with a top-level data node.  A
+                 complete instance identifier is required for this
+                 type of path value.
+                 
+                 The special value '/' refers to all possible
+                 datastore contents.";
+            }
+          }
+        }
+        leaf access-operations {
+          type union {
+            type matchall-string-type;
+            type access-operations-type;
+          }
+          default "*";
+          description
+            "Access operations associated with this rule.
+             
+             This leaf matches if it has the value '*' or if the
+             bit corresponding to the requested operation is set.";
+        }
+        leaf action {
+          type action-type;
+          mandatory true;
+          description
+            "The access control action associated with the
+             rule.  If a rule is determined to match a
+             particular request, then this object is used
+             to determine whether to permit or deny the
+             request.";
+        }
+        leaf comment {
+          type string;
+          description
+            "A textual description of the access rule.";
+        }
+      }
+    }
+  }
+}
diff --git a/tools/lint/examples/module1.yang b/tools/lint/examples/module1.yang
new file mode 100644
index 0000000..1df7bf1
--- /dev/null
+++ b/tools/lint/examples/module1.yang
@@ -0,0 +1,5 @@
+module module1 {
+  namespace "urn:yanglint:module";
+  prefix m;
+  leaf m { type string; }
+}
diff --git a/tools/lint/examples/module1b.yang b/tools/lint/examples/module1b.yang
new file mode 100644
index 0000000..463c936
--- /dev/null
+++ b/tools/lint/examples/module1b.yang
@@ -0,0 +1,5 @@
+module module1b {
+  namespace "urn:yanglint:module";
+  prefix m;
+  leaf mb { type string; }
+}
diff --git a/tools/lint/examples/module2.yang b/tools/lint/examples/module2.yang
new file mode 100644
index 0000000..c87c764
--- /dev/null
+++ b/tools/lint/examples/module2.yang
@@ -0,0 +1,5 @@
+module module2 {
+  namespace "urn:yanglint:module";
+  prefix m;
+  leaf m { ttype string; }
+}
diff --git a/tools/lint/examples/module2.yin b/tools/lint/examples/module2.yin
new file mode 100644
index 0000000..af6cb50
--- /dev/null
+++ b/tools/lint/examples/module2.yin
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module name="module2"
+        xmlns="urn:ietf:params:xml:ns:yang:yin:1"
+        xmlns:m="urn:yanglint:module">
+  <namespace uri="urn:yanglint:module"/>
+  <prefix value="m"/>
+  <leaf name="m">
+    <type value="string"/>
+  </leaf>
+</module>
diff --git a/tools/lint/examples/module3.yang b/tools/lint/examples/module3.yang
new file mode 100644
index 0000000..63754b1
--- /dev/null
+++ b/tools/lint/examples/module3.yang
@@ -0,0 +1,8 @@
+module module3 {
+  namespace "urn:yanglint:module";
+  prefix m;
+  leaf m { type string; must "../c/a"; }
+  container c {
+    leaf b { type string; }
+  }
+}
diff --git a/tools/lint/examples/module4.yang b/tools/lint/examples/module4.yang
new file mode 100644
index 0000000..23ea289
--- /dev/null
+++ b/tools/lint/examples/module4.yang
@@ -0,0 +1,52 @@
+module module4 {
+  yang-version 1.1;
+  namespace "urn:module4";
+  prefix m4;
+
+  container cont1 {
+    list list {
+      key "leaf1";
+      leaf leaf1 {
+        type string;
+      }
+      action act {
+        input {
+          leaf leaf2 {
+            type string;
+          }
+        }
+        output {
+          leaf leaf3 {
+            type string;
+          }
+        }
+      }
+      notification notif1 {
+        leaf leaf4 {
+          type string;
+        }
+      }
+    }
+  }
+
+  rpc rpc {
+    input {
+      leaf leaf5 {
+        type string;
+      }
+    }
+    output {
+      container cont2 {
+        leaf leaf6 {
+          type empty;
+        }
+      }
+    }
+  }
+
+  notification notif2 {
+    leaf leaf7 {
+      type empty;
+    }
+  }
+}
diff --git a/tools/lint/examples/nested-notification.xml b/tools/lint/examples/nested-notification.xml
new file mode 100644
index 0000000..024b65a
--- /dev/null
+++ b/tools/lint/examples/nested-notification.xml
@@ -0,0 +1,8 @@
+<cont1 xmlns="urn:module4">
+  <list>
+    <leaf1>key_val</leaf1>
+    <notif1>
+      <leaf4>some_value</leaf4>
+    </notif1>
+  </list>
+</cont1>
diff --git a/tools/lint/examples/notification.xml b/tools/lint/examples/notification.xml
new file mode 100644
index 0000000..803ddad
--- /dev/null
+++ b/tools/lint/examples/notification.xml
@@ -0,0 +1,3 @@
+<notif2 xmlns="urn:module4">
+  <leaf7/>
+</notif2>
diff --git a/tools/lint/examples/rpc-reply.xml b/tools/lint/examples/rpc-reply.xml
new file mode 100644
index 0000000..54aab3e
--- /dev/null
+++ b/tools/lint/examples/rpc-reply.xml
@@ -0,0 +1,5 @@
+<rpc xmlns="urn:module4">
+  <cont2>
+    <leaf6/>
+  </cont2>
+</rpc>
diff --git a/tools/lint/examples/rpc.xml b/tools/lint/examples/rpc.xml
new file mode 100644
index 0000000..ea8ca90
--- /dev/null
+++ b/tools/lint/examples/rpc.xml
@@ -0,0 +1,3 @@
+<rpc xmlns="urn:module4">
+  <leaf5>some_input</leaf5>
+</rpc>
diff --git a/tools/lint/examples/sm-context-extension.xml b/tools/lint/examples/sm-context-extension.xml
new file mode 100644
index 0000000..747c60f
--- /dev/null
+++ b/tools/lint/examples/sm-context-extension.xml
@@ -0,0 +1,64 @@
+<yang-library xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-library"
+     xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
+   <module-set>
+     <name>test-set</name>
+     <module>
+       <name>ietf-datastores</name>
+       <revision>2018-02-14</revision>
+       <namespace>urn:ietf:params:xml:ns:yang:ietf-datastores</namespace>
+     </module>
+     <module>
+       <name>ietf-yang-library</name>
+       <revision>2019-01-04</revision>
+       <namespace>urn:ietf:params:xml:ns:yang:ietf-yang-library</namespace>
+     </module>
+     <module>
+       <name>sm-extension</name>
+       <namespace>urn:sm-ext</namespace>
+     </module>
+     <module>
+       <name>iana-if-type</name>
+       <namespace>urn:ietf:params:xml:ns:yang:iana-if-type</namespace>
+     </module>
+     <import-only-module>
+       <name>ietf-yang-types</name>
+       <revision>2013-07-15</revision>
+       <namespace>urn:ietf:params:xml:ns:yang:ietf-yang-types</namespace>
+     </import-only-module>
+     <import-only-module>
+       <name>sm-mod</name>
+       <revision>2017-01-26</revision>
+       <namespace>urn:yanglint:sm-mod</namespace>
+     </import-only-module>
+   </module-set>
+   <schema>
+     <name>test-schema</name>
+     <module-set>test-set</module-set>
+   </schema>
+   <datastore>
+     <name>ds:running</name>
+     <schema>test-schema</schema>
+   </datastore>
+   <datastore>
+     <name>ds:operational</name>
+     <schema>test-schema</schema>
+   </datastore>
+   <content-id>1</content-id>
+ </yang-library>
+ <modules-state xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-library">
+   <module-set-id>1</module-set-id>
+ </modules-state>
+ <schema-mounts xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-schema-mount">
+   <namespace>
+     <prefix>if</prefix>
+     <uri>urn:ietf:params:xml:ns:yang:ietf-interfaces</uri>
+   </namespace>
+   <mount-point>
+     <module>sm-main</module>
+     <label>mnt-root</label>
+     <shared-schema>
+       <parent-reference>/if:interfaces/if:interface/if:name</parent-reference>
+       <parent-reference>/if:interfaces/if:interface/if:type</parent-reference>
+     </shared-schema>
+   </mount-point>
+  </schema-mounts>
diff --git a/tools/lint/examples/sm-context-main.xml b/tools/lint/examples/sm-context-main.xml
new file mode 100644
index 0000000..43558c3
--- /dev/null
+++ b/tools/lint/examples/sm-context-main.xml
@@ -0,0 +1,54 @@
+<yang-library xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-library"
+     xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
+   <module-set>
+     <name>main-set</name>
+     <module>
+       <name>ietf-datastores</name>
+       <revision>2018-02-14</revision>
+       <namespace>urn:ietf:params:xml:ns:yang:ietf-datastores</namespace>
+     </module>
+     <module>
+       <name>ietf-yang-library</name>
+       <revision>2019-01-04</revision>
+       <namespace>urn:ietf:params:xml:ns:yang:ietf-yang-library</namespace>
+     </module>
+     <module>
+       <name>ietf-yang-schema-mount</name>
+       <revision>2019-01-14</revision>
+       <namespace>urn:ietf:params:xml:ns:yang:ietf-yang-schema-mount</namespace>
+     </module>
+     <module>
+       <name>sm-main</name>
+       <namespace>urn:sm-main</namespace>
+     </module>
+     <module>
+       <name>iana-if-type</name>
+       <namespace>urn:ietf:params:xml:ns:yang:iana-if-type</namespace>
+     </module>
+     <module>
+       <name>ietf-interfaces</name>
+       <namespace>urn:ietf:params:xml:ns:yang:ietf-interfaces</namespace>
+     </module>
+     <import-only-module>
+       <name>ietf-yang-types</name>
+       <revision>2013-07-15</revision>
+       <namespace>urn:ietf:params:xml:ns:yang:ietf-yang-types</namespace>
+     </import-only-module>
+   </module-set>
+   <schema>
+     <name>main-schema</name>
+     <module-set>main-set</module-set>
+   </schema>
+   <datastore>
+     <name>ds:running</name>
+     <schema>main-schema</schema>
+   </datastore>
+   <datastore>
+     <name>ds:operational</name>
+     <schema>main-schema</schema>
+   </datastore>
+   <content-id>1</content-id>
+ </yang-library>
+ <modules-state xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-library">
+   <module-set-id>2</module-set-id>
+ </modules-state>
diff --git a/tools/lint/examples/sm-data.xml b/tools/lint/examples/sm-data.xml
new file mode 100644
index 0000000..478d324
--- /dev/null
+++ b/tools/lint/examples/sm-data.xml
@@ -0,0 +1,19 @@
+<interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
+  <interface>
+    <name>eth0</name>
+    <type xmlns:ift="urn:ietf:params:xml:ns:yang:iana-if-type">ift:ethernetCsmacd</type>
+  </interface>
+  <interface>
+    <name>eth1</name>
+    <type xmlns:ift="urn:ietf:params:xml:ns:yang:iana-if-type">ift:ethernetCsmacd</type>
+  </interface>
+</interfaces>
+<root3 xmlns="urn:sm-main">
+  <my-list>
+    <name>list item 1</name>
+    <things xmlns="urn:sm-ext">
+      <name>eth0</name>
+      <attribute>1</attribute>
+    </things>
+  </my-list>
+</root3>
diff --git a/tools/lint/examples/sm-extension.yang b/tools/lint/examples/sm-extension.yang
new file mode 100644
index 0000000..2214cf6
--- /dev/null
+++ b/tools/lint/examples/sm-extension.yang
@@ -0,0 +1,39 @@
+module sm-extension {
+    yang-version 1.1;
+    namespace "urn:sm-ext";
+    prefix "sm-ext";
+
+    import ietf-interfaces {
+        prefix if;
+    }
+    import sm-mod {
+        prefix sm-mod;
+    }
+
+    revision 2022-09-15 {
+      description
+        "initial";
+      reference
+        "";
+    }
+
+    list things {
+        key "name";
+        leaf name {
+            type leafref {
+              path "/if:interfaces/if:interface/if:name";
+            }
+        }
+        leaf attribute {
+            type uint32;
+        }
+    }
+
+    augment "/if:interfaces/if:interface" {
+        leaf thing-attribute {
+            type leafref {
+              path "/things/attribute";
+            }
+        }
+    }
+}
diff --git a/tools/lint/examples/sm-main.yang b/tools/lint/examples/sm-main.yang
new file mode 100644
index 0000000..53df6b6
--- /dev/null
+++ b/tools/lint/examples/sm-main.yang
@@ -0,0 +1,32 @@
+module sm-main {
+    yang-version 1.1;
+    namespace "urn:sm-main";
+    prefix "sm-main";
+
+    import ietf-yang-schema-mount {
+        prefix yangmnt;
+    }
+    import ietf-interfaces {
+        prefix if;
+    }
+
+    list root {
+        key "node";
+        leaf node {
+            type string;
+        }
+        yangmnt:mount-point "root";
+    }
+    container root2 {
+        yangmnt:mount-point "root";
+    }
+    container root3 {
+        list my-list {
+            key name;
+            leaf name {
+                type string;
+            }
+            yangmnt:mount-point "mnt-root";
+        }
+    }
+}
diff --git a/tools/lint/examples/sm-mod.yang b/tools/lint/examples/sm-mod.yang
new file mode 100644
index 0000000..79d1a50
--- /dev/null
+++ b/tools/lint/examples/sm-mod.yang
@@ -0,0 +1,21 @@
+module sm-mod {
+    yang-version 1.1;
+    namespace "urn:yanglint:sm-mod";
+    prefix "sm-mod";
+
+    revision 2017-01-26 {
+      description
+        "initial";
+      reference
+        "";
+    }
+
+    container not-compiled {
+        leaf first {
+            type string;
+        }
+        leaf second {
+            type string;
+        }
+    }
+}
diff --git a/tools/lint/linenoise/LICENSE b/tools/lint/linenoise/LICENSE
new file mode 100644
index 0000000..18e8148
--- /dev/null
+++ b/tools/lint/linenoise/LICENSE
@@ -0,0 +1,25 @@
+Copyright (c) 2010-2014, Salvatore Sanfilippo <antirez at gmail dot com>
+Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice,
+  this list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/tools/lint/linenoise/linenoise.c b/tools/lint/linenoise/linenoise.c
new file mode 100644
index 0000000..fed3d26
--- /dev/null
+++ b/tools/lint/linenoise/linenoise.c
@@ -0,0 +1,1218 @@
+/* linenoise.c -- VERSION 1.0
+ *
+ * Guerrilla line editing library against the idea that a line editing lib
+ * needs to be 20,000 lines of C code.
+ *
+ * You can find the latest source code at:
+ *
+ *   http://github.com/antirez/linenoise
+ *
+ * Does a number of crazy assumptions that happen to be true in 99.9999% of
+ * the 2010 UNIX computers around.
+ *
+ * ------------------------------------------------------------------------
+ *
+ * Copyright (c) 2010-2014, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *  *  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *
+ *  *  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * ------------------------------------------------------------------------
+ *
+ * References:
+ * - http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
+ * - http://www.3waylabs.com/nw/WWW/products/wizcon/vt220.html
+ *
+ * Todo list:
+ * - Filter bogus Ctrl+<char> combinations.
+ * - Win32 support
+ *
+ * Bloat:
+ * - History search like Ctrl+r in readline?
+ *
+ * List of escape sequences used by this program, we do everything just
+ * with three sequences. In order to be so cheap we may have some
+ * flickering effect with some slow terminal, but the lesser sequences
+ * the more compatible.
+ *
+ * EL (Erase Line)
+ *    Sequence: ESC [ n K
+ *    Effect: if n is 0 or missing, clear from cursor to end of line
+ *    Effect: if n is 1, clear from beginning of line to cursor
+ *    Effect: if n is 2, clear entire line
+ *
+ * CUF (CUrsor Forward)
+ *    Sequence: ESC [ n C
+ *    Effect: moves cursor forward n chars
+ *
+ * CUB (CUrsor Backward)
+ *    Sequence: ESC [ n D
+ *    Effect: moves cursor backward n chars
+ *
+ * The following is used to get the terminal width if getting
+ * the width with the TIOCGWINSZ ioctl fails
+ *
+ * DSR (Device Status Report)
+ *    Sequence: ESC [ 6 n
+ *    Effect: reports the current cusor position as ESC [ n ; m R
+ *            where n is the row and m is the column
+ *
+ * When multi line mode is enabled, we also use an additional escape
+ * sequence. However multi line editing is disabled by default.
+ *
+ * CUU (Cursor Up)
+ *    Sequence: ESC [ n A
+ *    Effect: moves cursor up of n chars.
+ *
+ * CUD (Cursor Down)
+ *    Sequence: ESC [ n B
+ *    Effect: moves cursor down of n chars.
+ *
+ * When linenoiseClearScreen() is called, two additional escape sequences
+ * are used in order to clear the screen and position the cursor at home
+ * position.
+ *
+ * CUP (Cursor position)
+ *    Sequence: ESC [ H
+ *    Effect: moves the cursor to upper left corner
+ *
+ * ED (Erase display)
+ *    Sequence: ESC [ 2 J
+ *    Effect: clear the whole screen
+ *
+ */
+
+#define _GNU_SOURCE
+#define _POSIX_C_SOURCE 200809L /* strdup */
+
+#include "linenoise.h"
+
+#include <ctype.h>
+#include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <termios.h>
+#include <unistd.h>
+
+#define LINENOISE_DEFAULT_HISTORY_MAX_LEN 100
+#define LINENOISE_MAX_LINE 4096
+static char *unsupported_term[] = {"dumb","cons25","emacs",NULL};
+static linenoiseCompletionCallback *completionCallback = NULL;
+
+static struct termios orig_termios; /* In order to restore at exit.*/
+static int mlmode = 0;  /* Multi line mode. Default is single line. */
+static int atexit_registered = 0; /* Register atexit just 1 time. */
+static int history_max_len = LINENOISE_DEFAULT_HISTORY_MAX_LEN;
+static int history_len = 0;
+static char **history = NULL;
+
+/* The linenoiseState structure represents the state during line editing.
+ * We pass this state to functions implementing specific editing
+ * functionalities. */
+struct linenoiseState lss;
+
+enum KEY_ACTION{
+    KEY_NULL = 0,	    /* NULL */
+    CTRL_A = 1,         /* Ctrl+a */
+    CTRL_B = 2,         /* Ctrl-b */
+    CTRL_C = 3,         /* Ctrl-c */
+    CTRL_D = 4,         /* Ctrl-d */
+    CTRL_E = 5,         /* Ctrl-e */
+    CTRL_F = 6,         /* Ctrl-f */
+    CTRL_H = 8,         /* Ctrl-h */
+    TAB = 9,            /* Tab */
+    CTRL_K = 11,        /* Ctrl+k */
+    CTRL_L = 12,        /* Ctrl+l */
+    ENTER = 13,         /* Enter */
+    CTRL_N = 14,        /* Ctrl-n */
+    CTRL_P = 16,        /* Ctrl-p */
+    CTRL_T = 20,        /* Ctrl-t */
+    CTRL_U = 21,        /* Ctrl+u */
+    CTRL_W = 23,        /* Ctrl+w */
+    ESC = 27,           /* Escape */
+    BACKSPACE =  127    /* Backspace */
+};
+
+static void linenoiseAtExit(void);
+int linenoiseHistoryAdd(const char *line);
+
+/* Debugging macro. */
+#if 0
+FILE *lndebug_fp = NULL;
+#define lndebug(...) \
+    do { \
+        if (lndebug_fp == NULL) { \
+            lndebug_fp = fopen("/tmp/lndebug.txt","a"); \
+            fprintf(lndebug_fp, \
+            "[%d %d %d] p: %d, rows: %d, rpos: %d, max: %d, oldmax: %d\n", \
+            (int)l->len,(int)l->pos,(int)l->oldpos,plen,rows,rpos, \
+            (int)l->maxrows,old_rows); \
+        } \
+        fprintf(lndebug_fp, ", " __VA_ARGS__); \
+        fflush(lndebug_fp); \
+    } while (0)
+#else
+#define lndebug(...)
+#endif
+
+/* ======================= Low level terminal handling ====================== */
+
+/* Set if to use or not the multi line mode. */
+void linenoiseSetMultiLine(int ml) {
+    mlmode = ml;
+}
+
+/* Return true if the terminal name is in the list of terminals we know are
+ * not able to understand basic escape sequences. */
+static int isUnsupportedTerm(void) {
+    char *term = getenv("TERM");
+    int j;
+
+    if (term == NULL) return 0;
+    for (j = 0; unsupported_term[j]; j++)
+        if (!strcasecmp(term,unsupported_term[j])) return 1;
+    return 0;
+}
+
+/* Raw mode: 1960 magic shit. */
+int linenoiseEnableRawMode(int fd) {
+    struct termios raw;
+
+    if (!isatty(STDIN_FILENO)) goto fatal;
+    if (!atexit_registered) {
+        atexit(linenoiseAtExit);
+        atexit_registered = 1;
+    }
+    if (tcgetattr(fd,&orig_termios) == -1) goto fatal;
+
+    raw = orig_termios;  /* modify the original mode */
+    /* input modes: no break, no CR to NL, no parity check, no strip char,
+     * no start/stop output control. */
+    raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
+    /* output modes - disable post processing */
+    raw.c_oflag &= ~(OPOST);
+    /* control modes - set 8 bit chars */
+    raw.c_cflag |= (CS8);
+    /* local modes - choing off, canonical off, no extended functions,
+     * no signal chars (^Z,^C) */
+    raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
+    /* control chars - set return condition: min number of bytes and timer.
+     * We want read to return every single byte, without timeout. */
+    raw.c_cc[VMIN] = 1; raw.c_cc[VTIME] = 0; /* 1 byte, no timer */
+
+    /* put terminal in raw mode after flushing */
+    if (tcsetattr(fd,TCSAFLUSH,&raw) < 0) goto fatal;
+    lss.rawmode = 1;
+    return 0;
+
+fatal:
+    errno = ENOTTY;
+    return -1;
+}
+
+void linenoiseDisableRawMode(int fd) {
+    /* Don't even check the return value as it's too late. */
+    if (lss.rawmode && tcsetattr(fd,TCSAFLUSH,&orig_termios) != -1)
+        lss.rawmode = 0;
+}
+
+/* Use the ESC [6n escape sequence to query the horizontal cursor position
+ * and return it. On error -1 is returned, on success the position of the
+ * cursor. */
+static int getCursorPosition(int ifd, int ofd) {
+    char buf[32];
+    int cols, rows;
+    unsigned int i = 0;
+
+    /* Report cursor location */
+    if (write(ofd, "\x1b[6n", 4) != 4) return -1;
+
+    /* Read the response: ESC [ rows ; cols R */
+    while (i < sizeof(buf)-1) {
+        if (read(ifd,buf+i,1) != 1) break;
+        if (buf[i] == 'R') break;
+        i++;
+    }
+    buf[i] = '\0';
+
+    /* Parse it. */
+    if (buf[0] != ESC || buf[1] != '[') return -1;
+    if (sscanf(buf+2,"%d;%d",&rows,&cols) != 2) return -1;
+    return cols;
+}
+
+/* Try to get the number of columns in the current terminal, or assume 80
+ * if it fails. */
+static int getColumns(int ifd, int ofd) {
+    struct winsize ws;
+
+    if (ioctl(1, TIOCGWINSZ, &ws) == -1 || ws.ws_col == 0) {
+        /* ioctl() failed. Try to query the terminal itself. */
+        int start, cols;
+
+        /* Get the initial position so we can restore it later. */
+        start = getCursorPosition(ifd,ofd);
+        if (start == -1) goto failed;
+
+        /* Go to right margin and get position. */
+        if (write(ofd,"\x1b[999C",6) != 6) goto failed;
+        cols = getCursorPosition(ifd,ofd);
+        if (cols == -1) goto failed;
+
+        /* Restore position. */
+        if (cols > start) {
+            char seq[32];
+            snprintf(seq,32,"\x1b[%dD",cols-start);
+            if (write(ofd,seq,strlen(seq)) == -1) {
+                /* Can't recover... */
+            }
+        }
+        return cols;
+    } else {
+        return ws.ws_col;
+    }
+
+failed:
+    return 80;
+}
+
+/* Clear the screen. Used to handle ctrl+l */
+void linenoiseClearScreen(void) {
+    if (write(STDOUT_FILENO,"\x1b[H\x1b[2J",7) <= 0) {
+        /* nothing to do, just to avoid warning. */
+    }
+}
+
+/* Beep, used for completion when there is nothing to complete or when all
+ * the choices were already shown. */
+static void linenoiseBeep(void) {
+    fprintf(stderr, "\x7");
+    fflush(stderr);
+}
+
+/* ============================== Completion ================================ */
+
+/* Free a list of completion option populated by linenoiseAddCompletion(). */
+static void freeCompletions(linenoiseCompletions *lc) {
+    size_t i;
+    for (i = 0; i < lc->len; i++)
+        free(lc->cvec[i]);
+    if (lc->cvec != NULL)
+        free(lc->cvec);
+}
+
+/* This is an helper function for linenoiseEdit() and is called when the
+ * user types the <tab> key in order to complete the string currently in the
+ * input.
+ *
+ * The state of the editing is encapsulated into the pointed linenoiseState
+ * structure as described in the structure definition. */
+static char completeLine(struct linenoiseState *ls) {
+    linenoiseCompletions lc = {0, 0, NULL};
+    int nread, nwritten, hint_len, hint_line_count, char_count;
+    char c = 0, *common, *hint;
+    struct winsize w;
+
+    /* Hint is only the string after the last space */
+    hint = strrchr(ls->buf, ' ');
+    if (!hint) {
+        hint = ls->buf;
+    } else {
+        ++hint;
+    }
+
+    completionCallback(ls->buf, hint, &lc);
+    if (lc.len == 0) {
+        linenoiseBeep();
+    } else {
+        unsigned int i, j;
+
+        /* Learn the longest common part */
+        common = strdup(lc.cvec[0]);
+        for (i = 1; i < lc.len; ++i) {
+            for (j = 0; j < strlen(lc.cvec[i]); ++j) {
+                if (lc.cvec[i][j] != common[j]) {
+                    break;
+                }
+            }
+            common[j] = '\0';
+        }
+
+        /* Path completions have a different hint */
+        if (lc.path && strrchr(hint, '/')) {
+            hint = strrchr(hint, '/');
+            ++hint;
+        }
+
+        /* Show completion */
+        if ((lc.len == 1) && (common[strlen(common) - 1] != '/')) {
+            nwritten = snprintf(hint, ls->buflen - (hint - ls->buf), "%s ", common);
+        } else {
+            nwritten = snprintf(hint, ls->buflen - (hint - ls->buf), "%s", common);
+        }
+        free(common);
+        ls->len = ls->pos = (hint - ls->buf) + nwritten;
+        linenoiseRefreshLine();
+
+        /* A single hint */
+        if (lc.len == 1) {
+            freeCompletions(&lc);
+            return 0;
+        }
+
+        /* Read a char */
+        nread = read(ls->ifd,&c,1);
+        if (nread <= 0) {
+            freeCompletions(&lc);
+            return -1;
+        }
+
+        /* Not a tab */
+        if (c != 9) {
+            freeCompletions(&lc);
+            return c;
+        }
+
+        /* Learn terminal window size */
+        ioctl(ls->ifd, TIOCGWINSZ, &w);
+
+        /* Learn the longest hint */
+        hint_len = strlen(lc.cvec[0]);
+        for (i = 1; i < lc.len; ++i) {
+            if (strlen(lc.cvec[i]) > (unsigned)hint_len) {
+                hint_len = strlen(lc.cvec[i]);
+            }
+        }
+
+        /* Learn the number of hints that fit a line */
+        hint_line_count = 0;
+        do {
+            /* Still fits, always at least one hint */
+            ++hint_line_count;
+
+            char_count = 0;
+            if (hint_line_count) {
+                char_count += hint_line_count * (hint_len + 2);
+            }
+            char_count += hint_len;
+
+            /* Too much */
+        } while (char_count <= w.ws_col);
+
+        while (c == 9) {
+            /* Second tab */
+            linenoiseDisableRawMode(ls->ifd);
+            printf("\n");
+            for (i = 0; i < lc.len; ++i) {
+                printf("%-*s", hint_len, lc.cvec[i]);
+                /* Line full or last hint */
+                if (((i + 1) % hint_line_count == 0) || (i == lc.len - 1)) {
+                    printf("\n");
+                } else {
+                    printf("  ");
+                }
+            }
+            linenoiseEnableRawMode(ls->ifd);
+            linenoiseRefreshLine();
+
+            /* Read a char */
+            nread = read(ls->ifd,&c,1);
+            if (nread <= 0) {
+                freeCompletions(&lc);
+                return -1;
+            }
+        }
+    }
+
+    freeCompletions(&lc);
+    return c; /* Return last read character */
+}
+
+/* Register a callback function to be called for tab-completion. */
+void linenoiseSetCompletionCallback(linenoiseCompletionCallback *fn) {
+    completionCallback = fn;
+}
+
+/* This function can be called in user completion callback to fill
+ * path completion for them. hint parameter is actually the whole path
+ * and buf is unused, but included to match the completion callback prototype. */
+void linenoisePathCompletion(const char *buf, const char *hint, linenoiseCompletions *lc) {
+    const char *ptr;
+    char *full_path, *hint_ptr, match[FILENAME_MAX + 2];
+    DIR *dir;
+    struct dirent *ent;
+    struct stat st;
+
+    (void)buf;
+
+    lc->path = 1;
+
+    ptr = strrchr(hint, '/');
+
+    /* new relative path */
+    if (ptr == NULL) {
+        full_path = malloc(2 + FILENAME_MAX + 1);
+        strcpy(full_path, "./");
+
+        ptr = hint;
+    } else {
+        full_path = malloc((int)(ptr - hint) + FILENAME_MAX + 1);
+        ++ptr;
+        sprintf(full_path, "%.*s", (int)(ptr - hint), hint);
+    }
+    hint_ptr = full_path + strlen(full_path);
+
+    dir = opendir(full_path);
+    if (dir == NULL) {
+        free(full_path);
+        return;
+    }
+
+    while ((ent = readdir(dir))) {
+        if (ent->d_name[0] == '.') {
+            continue;
+        }
+
+        if (!strncmp(ptr, ent->d_name, strlen(ptr))) {
+            /* is it a directory? */
+            strcpy(hint_ptr, ent->d_name);
+            if (stat(full_path, &st)) {
+                /* skip this item */
+                continue;
+            }
+
+            strcpy(match, ent->d_name);
+            if (S_ISDIR(st.st_mode)) {
+                strcat(match, "/");
+            }
+
+            linenoiseAddCompletion(lc, match);
+        }
+    }
+
+    free(full_path);
+    closedir(dir);
+}
+
+/* This function is used by the callback function registered by the user
+ * in order to add completion options given the input string when the
+ * user typed <tab>. See the example.c source code for a very easy to
+ * understand example. */
+void linenoiseAddCompletion(linenoiseCompletions *lc, const char *str) {
+    size_t len = strlen(str);
+    char *copy, **cvec;
+
+    copy = malloc(len+1);
+    if (copy == NULL) return;
+    memcpy(copy,str,len+1);
+    cvec = realloc(lc->cvec,sizeof(char*)*(lc->len+1));
+    if (cvec == NULL) {
+        free(copy);
+        return;
+    }
+    lc->cvec = cvec;
+    lc->cvec[lc->len++] = copy;
+}
+
+/* =========================== Line editing ================================= */
+
+/* We define a very simple "append buffer" structure, that is an heap
+ * allocated string where we can append to. This is useful in order to
+ * write all the escape sequences in a buffer and flush them to the standard
+ * output in a single call, to avoid flickering effects. */
+struct abuf {
+    char *b;
+    int len;
+};
+
+static void abInit(struct abuf *ab) {
+    ab->b = NULL;
+    ab->len = 0;
+}
+
+static void abAppend(struct abuf *ab, const char *s, int len) {
+    char *new = realloc(ab->b,ab->len+len);
+
+    if (new == NULL) return;
+    memcpy(new+ab->len,s,len);
+    ab->b = new;
+    ab->len += len;
+}
+
+static void abFree(struct abuf *ab) {
+    free(ab->b);
+}
+
+/* Single line low level line refresh.
+ *
+ * Rewrite the currently edited line accordingly to the buffer content,
+ * cursor position, and number of columns of the terminal. */
+static void refreshSingleLine(struct linenoiseState *l) {
+    char seq[64];
+    size_t plen = strlen(l->prompt);
+    int fd = l->ofd;
+    char *buf = l->buf;
+    size_t len = l->len;
+    size_t pos = l->pos;
+    struct abuf ab;
+
+    while((plen+pos) >= l->cols) {
+        buf++;
+        len--;
+        pos--;
+    }
+    while (plen+len > l->cols) {
+        len--;
+    }
+
+    abInit(&ab);
+    /* Cursor to left edge */
+    snprintf(seq,64,"\r");
+    abAppend(&ab,seq,strlen(seq));
+    /* Write the prompt and the current buffer content */
+    abAppend(&ab,l->prompt,strlen(l->prompt));
+    abAppend(&ab,buf,len);
+    /* Erase to right */
+    snprintf(seq,64,"\x1b[0K");
+    abAppend(&ab,seq,strlen(seq));
+    /* Move cursor to original position. */
+    snprintf(seq,64,"\r\x1b[%dC", (int)(pos+plen));
+    abAppend(&ab,seq,strlen(seq));
+    if (write(fd,ab.b,ab.len) == -1) {} /* Can't recover from write error. */
+    abFree(&ab);
+}
+
+/* Multi line low level line refresh.
+ *
+ * Rewrite the currently edited line accordingly to the buffer content,
+ * cursor position, and number of columns of the terminal. */
+static void refreshMultiLine(struct linenoiseState *l) {
+    char seq[64];
+    int plen = strlen(l->prompt);
+    int rows = (plen+l->len+l->cols-1)/l->cols; /* rows used by current buf. */
+    int rpos = (plen+l->oldpos+l->cols)/l->cols; /* cursor relative row. */
+    int rpos2; /* rpos after refresh. */
+    int col; /* colum position, zero-based. */
+    int old_rows = l->maxrows;
+    int fd = l->ofd, j;
+    struct abuf ab;
+
+    /* Update maxrows if needed. */
+    if (rows > (int)l->maxrows) l->maxrows = rows;
+
+    /* First step: clear all the lines used before. To do so start by
+     * going to the last row. */
+    abInit(&ab);
+    if (old_rows-rpos > 0) {
+        lndebug("go down %d", old_rows-rpos);
+        snprintf(seq,64,"\x1b[%dB", old_rows-rpos);
+        abAppend(&ab,seq,strlen(seq));
+    }
+
+    /* Now for every row clear it, go up. */
+    for (j = 0; j < old_rows-1; j++) {
+        lndebug("clear+up");
+        snprintf(seq,64,"\r\x1b[0K\x1b[1A");
+        abAppend(&ab,seq,strlen(seq));
+    }
+
+    /* Clean the top line. */
+    lndebug("clear");
+    snprintf(seq,64,"\r\x1b[0K");
+    abAppend(&ab,seq,strlen(seq));
+
+    /* Write the prompt and the current buffer content */
+    abAppend(&ab,l->prompt,strlen(l->prompt));
+    abAppend(&ab,l->buf,l->len);
+
+    /* If we are at the very end of the screen with our prompt, we need to
+     * emit a newline and move the prompt to the first column. */
+    if (l->pos &&
+        l->pos == l->len &&
+        (l->pos+plen) % l->cols == 0)
+    {
+        lndebug("<newline>");
+        abAppend(&ab,"\n",1);
+        snprintf(seq,64,"\r");
+        abAppend(&ab,seq,strlen(seq));
+        rows++;
+        if (rows > (int)l->maxrows) l->maxrows = rows;
+    }
+
+    /* Move cursor to right position. */
+    rpos2 = (plen+l->pos+l->cols)/l->cols; /* current cursor relative row. */
+    lndebug("rpos2 %d", rpos2);
+
+    /* Go up till we reach the expected positon. */
+    if (rows-rpos2 > 0) {
+        lndebug("go-up %d", rows-rpos2);
+        snprintf(seq,64,"\x1b[%dA", rows-rpos2);
+        abAppend(&ab,seq,strlen(seq));
+    }
+
+    /* Set column. */
+    col = (plen+(int)l->pos) % (int)l->cols;
+    lndebug("set col %d", 1+col);
+    if (col)
+        snprintf(seq,64,"\r\x1b[%dC", col);
+    else
+        snprintf(seq,64,"\r");
+    abAppend(&ab,seq,strlen(seq));
+
+    lndebug("\n");
+    l->oldpos = l->pos;
+
+    if (write(fd,ab.b,ab.len) == -1) {} /* Can't recover from write error. */
+    abFree(&ab);
+}
+
+/* Calls the two low level functions refreshSingleLine() or
+ * refreshMultiLine() according to the selected mode. */
+void linenoiseRefreshLine(void) {
+    /* Update columns in case the terminal was resized */
+    lss.cols = getColumns(STDIN_FILENO, STDOUT_FILENO);
+
+    if (mlmode)
+        refreshMultiLine(&lss);
+    else
+        refreshSingleLine(&lss);
+}
+
+/* Insert the character 'c' at cursor current position.
+ *
+ * On error writing to the terminal -1 is returned, otherwise 0. */
+int linenoiseEditInsert(struct linenoiseState *l, char c) {
+    if (l->len < l->buflen) {
+        if (l->len == l->pos) {
+            l->buf[l->pos] = c;
+            l->pos++;
+            l->len++;
+            l->buf[l->len] = '\0';
+            if ((!mlmode && l->plen+l->len < l->cols) /* || mlmode */) {
+                /* Avoid a full update of the line in the
+                 * trivial case. */
+                if (write(l->ofd,&c,1) == -1) return -1;
+            } else {
+                linenoiseRefreshLine();
+            }
+        } else {
+            memmove(l->buf+l->pos+1,l->buf+l->pos,l->len-l->pos);
+            l->buf[l->pos] = c;
+            l->len++;
+            l->pos++;
+            l->buf[l->len] = '\0';
+            linenoiseRefreshLine();
+        }
+    }
+    return 0;
+}
+
+/* Move cursor on the left. */
+void linenoiseEditMoveLeft(struct linenoiseState *l) {
+    if (l->pos > 0) {
+        l->pos--;
+        linenoiseRefreshLine();
+    }
+}
+
+/* Move cursor on the right. */
+void linenoiseEditMoveRight(struct linenoiseState *l) {
+    if (l->pos != l->len) {
+        l->pos++;
+        linenoiseRefreshLine();
+    }
+}
+
+/* Move cursor to the start of the line. */
+void linenoiseEditMoveHome(struct linenoiseState *l) {
+    if (l->pos != 0) {
+        l->pos = 0;
+        linenoiseRefreshLine();
+    }
+}
+
+/* Move cursor to the end of the line. */
+void linenoiseEditMoveEnd(struct linenoiseState *l) {
+    if (l->pos != l->len) {
+        l->pos = l->len;
+        linenoiseRefreshLine();
+    }
+}
+
+/* Substitute the currently edited line with the next or previous history
+ * entry as specified by 'dir'. */
+#define LINENOISE_HISTORY_NEXT 0
+#define LINENOISE_HISTORY_PREV 1
+void linenoiseEditHistoryNext(struct linenoiseState *l, int dir) {
+    if (history_len > 1) {
+        /* Update the current history entry before to
+         * overwrite it with the next one. */
+        free(history[history_len - 1 - l->history_index]);
+        history[history_len - 1 - l->history_index] = strdup(l->buf);
+        /* Show the new entry */
+        l->history_index += (dir == LINENOISE_HISTORY_PREV) ? 1 : -1;
+        if (l->history_index < 0) {
+            l->history_index = 0;
+            return;
+        } else if (l->history_index >= history_len) {
+            l->history_index = history_len-1;
+            return;
+        }
+        strncpy(l->buf,history[history_len - 1 - l->history_index],l->buflen);
+        l->buf[l->buflen-1] = '\0';
+        l->len = l->pos = strlen(l->buf);
+        linenoiseRefreshLine();
+    }
+}
+
+/* Delete the character at the right of the cursor without altering the cursor
+ * position. Basically this is what happens with the "Delete" keyboard key. */
+void linenoiseEditDelete(struct linenoiseState *l) {
+    if (l->len > 0 && l->pos < l->len) {
+        memmove(l->buf+l->pos,l->buf+l->pos+1,l->len-l->pos-1);
+        l->len--;
+        l->buf[l->len] = '\0';
+        linenoiseRefreshLine();
+    }
+}
+
+/* Backspace implementation. */
+void linenoiseEditBackspace(struct linenoiseState *l) {
+    if (l->pos > 0 && l->len > 0) {
+        memmove(l->buf+l->pos-1,l->buf+l->pos,l->len-l->pos);
+        l->pos--;
+        l->len--;
+        l->buf[l->len] = '\0';
+        linenoiseRefreshLine();
+    }
+}
+
+/* Delete the previosu word, maintaining the cursor at the start of the
+ * current word. */
+void linenoiseEditDeletePrevWord(struct linenoiseState *l) {
+    size_t old_pos = l->pos;
+    size_t diff;
+
+    while (l->pos > 0 && l->buf[l->pos-1] == ' ')
+        l->pos--;
+    while (l->pos > 0 && l->buf[l->pos-1] != ' ')
+        l->pos--;
+    diff = old_pos - l->pos;
+    memmove(l->buf+l->pos,l->buf+old_pos,l->len-old_pos+1);
+    l->len -= diff;
+    linenoiseRefreshLine();
+}
+
+/* This function is the core of the line editing capability of linenoise.
+ * It expects 'fd' to be already in "raw mode" so that every key pressed
+ * will be returned ASAP to read().
+ *
+ * The resulting string is put into 'buf' when the user type enter, or
+ * when ctrl+d is typed.
+ *
+ * The function returns the length of the current buffer. */
+static int linenoiseEdit(int stdin_fd, int stdout_fd, char *buf, size_t buflen, const char *prompt)
+{
+    /* Populate the linenoise state that we pass to functions implementing
+     * specific editing functionalities. */
+    lss.ifd = stdin_fd;
+    lss.ofd = stdout_fd;
+    lss.buf = buf;
+    lss.buflen = buflen;
+    lss.prompt = prompt;
+    lss.plen = strlen(prompt);
+    lss.oldpos = lss.pos = 0;
+    lss.len = 0;
+    lss.cols = getColumns(stdin_fd, stdout_fd);
+    lss.maxrows = 0;
+    lss.history_index = 0;
+
+    /* Buffer starts empty. */
+    lss.buf[0] = '\0';
+    lss.buflen--; /* Make sure there is always space for the nulterm */
+
+    /* The latest history entry is always our current buffer, that
+     * initially is just an empty string. */
+    linenoiseHistoryAdd("");
+
+    if (write(lss.ofd,prompt,lss.plen) == -1) return -1;
+    while(1) {
+        char c = 0;
+        int nread;
+        char seq[3];
+
+        nread = read(lss.ifd,&c,sizeof c);
+        if (nread <= 0) return lss.len;
+
+        /* Only autocomplete when the callback is set. It returns < 0 when
+         * there was an error reading from fd. Otherwise it will return the
+         * character that should be handled next. */
+        if (c == 9 && completionCallback != NULL) {
+            c = completeLine(&lss);
+            /* Return on errors */
+            if (c < 0) return lss.len;
+            /* Read next character when 0 */
+            if (c == 0) continue;
+        }
+
+        switch(c) {
+        case ENTER:    /* enter */
+            history_len--;
+            free(history[history_len]);
+            if (mlmode) linenoiseEditMoveEnd(&lss);
+            return (int)lss.len;
+        case CTRL_C:     /* ctrl-c */
+            errno = EAGAIN;
+            return -1;
+        case BACKSPACE:   /* backspace */
+        case 8:     /* ctrl-h */
+            linenoiseEditBackspace(&lss);
+            break;
+        case CTRL_D:     /* ctrl-d, remove char at right of cursor, or if the
+                            line is empty, act as end-of-file. */
+            if (lss.len > 0) {
+                linenoiseEditDelete(&lss);
+            } else {
+                history_len--;
+                free(history[history_len]);
+                return -1;
+            }
+            break;
+        case CTRL_T:    /* ctrl-t, swaps current character with previous. */
+            if (lss.pos > 0 && lss.pos < lss.len) {
+                int aux = buf[lss.pos-1];
+                buf[lss.pos-1] = buf[lss.pos];
+                buf[lss.pos] = aux;
+                if (lss.pos != lss.len-1) lss.pos++;
+                linenoiseRefreshLine();
+            }
+            break;
+        case CTRL_B:     /* ctrl-b */
+            linenoiseEditMoveLeft(&lss);
+            break;
+        case CTRL_F:     /* ctrl-f */
+            linenoiseEditMoveRight(&lss);
+            break;
+        case CTRL_P:    /* ctrl-p */
+            linenoiseEditHistoryNext(&lss, LINENOISE_HISTORY_PREV);
+            break;
+        case CTRL_N:    /* ctrl-n */
+            linenoiseEditHistoryNext(&lss, LINENOISE_HISTORY_NEXT);
+            break;
+        case ESC:    /* escape sequence */
+            /* Read the next two bytes representing the escape sequence.
+             * Use two calls to handle slow terminals returning the two
+             * chars at different times. */
+            if (read(lss.ifd,seq,1) == -1) break;
+            if (read(lss.ifd,seq+1,1) == -1) break;
+
+            /* ESC [ sequences. */
+            if (seq[0] == '[') {
+                if (seq[1] >= '0' && seq[1] <= '9') {
+                    /* Extended escape, read additional byte. */
+                    if (read(lss.ifd, seq + 2, 1) == -1) break;
+                    if ((seq[1] == '3') && (seq[2] == '~')) {
+                        /* Delete key. */
+                        linenoiseEditDelete(&lss);
+                    }
+                } else {
+                    switch(seq[1]) {
+                    case 'A': /* Up */
+                        linenoiseEditHistoryNext(&lss, LINENOISE_HISTORY_PREV);
+                        break;
+                    case 'B': /* Down */
+                        linenoiseEditHistoryNext(&lss, LINENOISE_HISTORY_NEXT);
+                        break;
+                    case 'C': /* Right */
+                        linenoiseEditMoveRight(&lss);
+                        break;
+                    case 'D': /* Left */
+                        linenoiseEditMoveLeft(&lss);
+                        break;
+                    case 'H': /* Home */
+                        linenoiseEditMoveHome(&lss);
+                        break;
+                    case 'F': /* End*/
+                        linenoiseEditMoveEnd(&lss);
+                        break;
+                    }
+                }
+            }
+
+            /* ESC O sequences. */
+            else if (seq[0] == 'O') {
+                switch(seq[1]) {
+                case 'H': /* Home */
+                    linenoiseEditMoveHome(&lss);
+                    break;
+                case 'F': /* End*/
+                    linenoiseEditMoveEnd(&lss);
+                    break;
+                }
+            }
+            break;
+        default:
+            if (linenoiseEditInsert(&lss,c)) return -1;
+            break;
+        case CTRL_U: /* Ctrl+u, delete the whole line. */
+            buf[0] = '\0';
+            lss.pos = lss.len = 0;
+            linenoiseRefreshLine();
+            break;
+        case CTRL_K: /* Ctrl+k, delete from current to end of line. */
+            buf[lss.pos] = '\0';
+            lss.len = lss.pos;
+            linenoiseRefreshLine();
+            break;
+        case CTRL_A: /* Ctrl+a, go to the start of the line */
+            linenoiseEditMoveHome(&lss);
+            break;
+        case CTRL_E: /* ctrl+e, go to the end of the line */
+            linenoiseEditMoveEnd(&lss);
+            break;
+        case CTRL_L: /* ctrl+l, clear screen */
+            linenoiseClearScreen();
+            linenoiseRefreshLine();
+            break;
+        case CTRL_W: /* ctrl+w, delete previous word */
+            linenoiseEditDeletePrevWord(&lss);
+            break;
+        }
+    }
+    return lss.len;
+}
+
+/* This special mode is used by linenoise in order to print scan codes
+ * on screen for debugging / development purposes. It is implemented
+ * by the linenoise_example program using the --keycodes option. */
+void linenoisePrintKeyCodes(void) {
+    char quit[4];
+
+    printf("Linenoise key codes debugging mode.\n"
+            "Press keys to see scan codes. Type 'quit' at any time to exit.\n");
+    if (linenoiseEnableRawMode(STDIN_FILENO) == -1) return;
+    memset(quit,' ',4);
+    while(1) {
+        char c;
+        int nread;
+
+        nread = read(STDIN_FILENO,&c,1);
+        if (nread <= 0) continue;
+        memmove(quit,quit+1,sizeof(quit)-1); /* shift string to left. */
+        quit[sizeof(quit)-1] = c; /* Insert current char on the right. */
+        if (memcmp(quit,"quit",sizeof(quit)) == 0) break;
+
+        printf("'%c' %02x (%d) (type quit to exit)\n",
+            isprint(c) ? c : '?', (int)c, (int)c);
+        printf("\r"); /* Go left edge manually, we are in raw mode. */
+        fflush(stdout);
+    }
+    linenoiseDisableRawMode(STDIN_FILENO);
+}
+
+/* This function calls the line editing function linenoiseEdit() using
+ * the STDIN file descriptor set in raw mode. */
+static int linenoiseRaw(char *buf, size_t buflen, const char *prompt) {
+    int count;
+
+    if (buflen == 0) {
+        errno = EINVAL;
+        return -1;
+    }
+    if (!isatty(STDIN_FILENO)) {
+        /* Not a tty: read from file / pipe. */
+        if (fgets(buf, buflen, stdin) == NULL) return -1;
+        count = strlen(buf);
+        if (count && buf[count-1] == '\n') {
+            count--;
+            buf[count] = '\0';
+        }
+    } else {
+        /* Interactive editing. */
+        if (linenoiseEnableRawMode(STDIN_FILENO) == -1) return -1;
+        count = linenoiseEdit(STDIN_FILENO, STDOUT_FILENO, buf, buflen, prompt);
+        linenoiseDisableRawMode(STDIN_FILENO);
+        printf("\n");
+    }
+    return count;
+}
+
+/* The high level function that is the main API of the linenoise library.
+ * This function checks if the terminal has basic capabilities, just checking
+ * for a blacklist of stupid terminals, and later either calls the line
+ * editing function or uses dummy fgets() so that you will be able to type
+ * something even in the most desperate of the conditions. */
+char *linenoise(const char *prompt) {
+    char buf[LINENOISE_MAX_LINE];
+    int count;
+
+    if (isUnsupportedTerm()) {
+        size_t len;
+
+        printf("%s",prompt);
+        fflush(stdout);
+        if (fgets(buf,LINENOISE_MAX_LINE,stdin) == NULL) return NULL;
+        len = strlen(buf);
+        while(len && (buf[len-1] == '\n' || buf[len-1] == '\r')) {
+            len--;
+            buf[len] = '\0';
+        }
+        return strdup(buf);
+    } else {
+        count = linenoiseRaw(buf,LINENOISE_MAX_LINE,prompt);
+        if (count == -1) return NULL;
+        return strdup(buf);
+    }
+}
+
+/* ================================ History ================================= */
+
+/* Free the history, but does not reset it. Only used when we have to
+ * exit() to avoid memory leaks are reported by valgrind & co. */
+static void freeHistory(void) {
+    if (history) {
+        int j;
+
+        for (j = 0; j < history_len; j++)
+            free(history[j]);
+        free(history);
+    }
+}
+
+/* At exit we'll try to fix the terminal to the initial conditions. */
+static void linenoiseAtExit(void) {
+    linenoiseDisableRawMode(STDIN_FILENO);
+    freeHistory();
+}
+
+/* This is the API call to add a new entry in the linenoise history.
+ * It uses a fixed array of char pointers that are shifted (memmoved)
+ * when the history max length is reached in order to remove the older
+ * entry and make room for the new one, so it is not exactly suitable for huge
+ * histories, but will work well for a few hundred of entries.
+ *
+ * Using a circular buffer is smarter, but a bit more complex to handle. */
+int linenoiseHistoryAdd(const char *line) {
+    char *linecopy;
+
+    if (history_max_len == 0) return 0;
+
+    /* Initialization on first call. */
+    if (history == NULL) {
+        history = malloc(sizeof(char*)*history_max_len);
+        if (history == NULL) return 0;
+        memset(history,0,(sizeof(char*)*history_max_len));
+    }
+
+    /* Don't add duplicated lines. */
+    if (history_len && !strcmp(history[history_len-1], line)) return 0;
+
+    /* Add an heap allocated copy of the line in the history.
+     * If we reached the max length, remove the older line. */
+    linecopy = strdup(line);
+    if (!linecopy) return 0;
+    if (history_len == history_max_len) {
+        free(history[0]);
+        memmove(history,history+1,sizeof(char*)*(history_max_len-1));
+        history_len--;
+    }
+    history[history_len] = linecopy;
+    history_len++;
+    return 1;
+}
+
+/* Set the maximum length for the history. This function can be called even
+ * if there is already some history, the function will make sure to retain
+ * just the latest 'len' elements if the new history length value is smaller
+ * than the amount of items already inside the history. */
+int linenoiseHistorySetMaxLen(int len) {
+    char **new;
+
+    if (len < 1) return 0;
+    if (history) {
+        int tocopy = history_len;
+
+        new = malloc(sizeof(char*)*len);
+        if (new == NULL) return 0;
+
+        /* If we can't copy everything, free the elements we'll not use. */
+        if (len < tocopy) {
+            int j;
+
+            for (j = 0; j < tocopy-len; j++) free(history[j]);
+            tocopy = len;
+        }
+        memset(new,0,sizeof(char*)*len);
+        memcpy(new,history+(history_len-tocopy), sizeof(char*)*tocopy);
+        free(history);
+        history = new;
+    }
+    history_max_len = len;
+    if (history_len > history_max_len)
+        history_len = history_max_len;
+    return 1;
+}
+
+/* Save the history in the specified file. On success 0 is returned
+ * otherwise -1 is returned. */
+int linenoiseHistorySave(const char *filename) {
+    FILE *fp = fopen(filename,"w");
+    int j;
+
+    if (fp == NULL) return -1;
+    for (j = 0; j < history_len; j++)
+        fprintf(fp,"%s\n",history[j]);
+    fclose(fp);
+    return 0;
+}
+
+/* Load the history from the specified file. If the file does not exist
+ * zero is returned and no operation is performed.
+ *
+ * If the file exists and the operation succeeded 0 is returned, otherwise
+ * on error -1 is returned. */
+int linenoiseHistoryLoad(const char *filename) {
+    FILE *fp = fopen(filename,"r");
+    char buf[LINENOISE_MAX_LINE];
+
+    if (fp == NULL) return -1;
+
+    while (fgets(buf,LINENOISE_MAX_LINE,fp) != NULL) {
+        char *p;
+
+        p = strchr(buf,'\r');
+        if (!p) p = strchr(buf,'\n');
+        if (p) *p = '\0';
+        linenoiseHistoryAdd(buf);
+    }
+    fclose(fp);
+    return 0;
+}
diff --git a/tools/lint/linenoise/linenoise.h b/tools/lint/linenoise/linenoise.h
new file mode 100644
index 0000000..8362b1f
--- /dev/null
+++ b/tools/lint/linenoise/linenoise.h
@@ -0,0 +1,94 @@
+/* linenoise.h -- VERSION 1.0
+ *
+ * Guerrilla line editing library against the idea that a line editing lib
+ * needs to be 20,000 lines of C code.
+ *
+ * See linenoise.c for more information.
+ *
+ * ------------------------------------------------------------------------
+ *
+ * Copyright (c) 2010-2014, Salvatore Sanfilippo <antirez at gmail dot com>
+ * Copyright (c) 2010-2013, Pieter Noordhuis <pcnoordhuis at gmail dot com>
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *  *  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *
+ *  *  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __LINENOISE_H
+#define __LINENOISE_H
+
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct linenoiseState {
+    int ifd;            /* Terminal stdin file descriptor. */
+    int ofd;            /* Terminal stdout file descriptor. */
+    char *buf;          /* Edited line buffer. */
+    size_t buflen;      /* Edited line buffer size. */
+    const char *prompt; /* Prompt to display. */
+    size_t plen;        /* Prompt length. */
+    size_t pos;         /* Current cursor position. */
+    size_t oldpos;      /* Previous refresh cursor position. */
+    size_t len;         /* Current edited line length. */
+    size_t cols;        /* Number of columns in terminal. */
+    size_t maxrows;     /* Maximum num of rows used so far (multiline mode) */
+    int rawmode;
+    int history_index;  /* The history index we are currently editing. */
+};
+
+extern struct linenoiseState lss;
+
+typedef struct linenoiseCompletions {
+    int path;
+    size_t len;
+    char **cvec;
+} linenoiseCompletions;
+
+typedef void(linenoiseCompletionCallback)(const char *, const char *, linenoiseCompletions *);
+void linenoiseSetCompletionCallback(linenoiseCompletionCallback *);
+void linenoiseAddCompletion(linenoiseCompletions *, const char *);
+
+char *linenoise(const char *prompt);
+int linenoiseHistoryAdd(const char *line);
+int linenoiseHistorySetMaxLen(int len);
+int linenoiseHistorySave(const char *filename);
+int linenoiseHistoryLoad(const char *filename);
+void linenoiseClearScreen(void);
+void linenoiseSetMultiLine(int ml);
+void linenoisePrintKeyCodes(void);
+
+void linenoisePathCompletion(const char *, const char *, linenoiseCompletions *);
+void linenoiseRefreshLine(void);
+int linenoiseEnableRawMode(int fd);
+void linenoiseDisableRawMode(int fd);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LINENOISE_H */
diff --git a/tools/lint/main.c b/tools/lint/main.c
new file mode 100644
index 0000000..9f0d027
--- /dev/null
+++ b/tools/lint/main.c
@@ -0,0 +1,102 @@
+/**
+ * @file main.c
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @brief libyang's yanglint tool
+ *
+ * Copyright (c) 2015-2020 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+#define _POSIX_C_SOURCE 200809L /* strdup */
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "libyang.h"
+
+#include "cmd.h"
+#include "common.h"
+#include "completion.h"
+#include "configuration.h"
+#include "linenoise/linenoise.h"
+
+int done;
+struct ly_ctx *ctx = NULL;
+
+/* main_ni.c */
+int main_ni(int argc, char *argv[]);
+
+int
+main(int argc, char *argv[])
+{
+    char *cmdline;
+    int cmdlen;
+
+    if (argc > 1) {
+        /* run in non-interactive mode */
+        return main_ni(argc, argv);
+    }
+
+    /* continue in interactive mode */
+    linenoiseSetCompletionCallback(complete_cmd);
+    load_config();
+
+    if (ly_ctx_new(NULL, YL_DEFAULT_CTX_OPTIONS, &ctx)) {
+        YLMSG_E("Failed to create context.\n");
+        return 1;
+    }
+
+    while (!done) {
+        uint8_t executed = 0;
+
+        /* get the command from user */
+        cmdline = linenoise(PROMPT);
+
+        /* EOF -> exit */
+        if (cmdline == NULL) {
+            done = 1;
+            cmdline = strdup("quit");
+        }
+
+        /* empty line -> wait for another command */
+        if (*cmdline == '\0') {
+            free(cmdline);
+            continue;
+        }
+
+        /* isolate the command word. */
+        for (cmdlen = 0; cmdline[cmdlen] && (cmdline[cmdlen] != ' '); cmdlen++) {}
+
+        /* execute the command if any valid specified */
+        for (uint16_t i = 0; commands[i].name; i++) {
+            if (strncmp(cmdline, commands[i].name, (size_t)cmdlen) || (commands[i].name[cmdlen] != '\0')) {
+                continue;
+            }
+
+            commands[i].func(&ctx, cmdline);
+            executed = 1;
+            break;
+        }
+
+        if (!executed) {
+            /* if unknown command specified, tell it to user */
+            YLMSG_E("Unknown command \"%.*s\", type 'help' for more information.\n", cmdlen, cmdline);
+        }
+
+        linenoiseHistoryAdd(cmdline);
+        free(cmdline);
+    }
+
+    store_config();
+    ly_ctx_destroy(ctx);
+
+    return 0;
+}
diff --git a/tools/lint/main_ni.c b/tools/lint/main_ni.c
new file mode 100644
index 0000000..04c2340
--- /dev/null
+++ b/tools/lint/main_ni.c
@@ -0,0 +1,1027 @@
+/**
+ * @file main_ni.c
+ * @author Radek Krejci <rkrejci@cesnet.cz>
+ * @author Michal Vasko <mvasko@cesnet.cz>
+ * @brief libyang's yanglint tool - non-interactive code
+ *
+ * Copyright (c) 2020 - 2022 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <getopt.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <sys/stat.h>
+
+#include "libyang.h"
+#include "plugins_exts.h"
+
+#include "common.h"
+#include "out.h"
+#include "tools/config.h"
+
+/**
+ * @brief Context structure to hold and pass variables in a structured form.
+ */
+struct context {
+    /* libyang context for the run */
+    const char *yang_lib_file;
+    uint16_t ctx_options;
+    struct ly_ctx *ctx;
+
+    /* prepared output (--output option or stdout by default) */
+    struct ly_out *out;
+
+    char *searchpaths;
+
+    /* options flags */
+    uint8_t list;        /* -l option to print list of schemas */
+
+    /* line length for 'tree' format */
+    size_t line_length; /* --tree-line-length */
+
+    /*
+     * schema
+     */
+    /* set schema modules' features via --features option (struct schema_features *) */
+    struct ly_set schema_features;
+
+    /* set of loaded schema modules (struct lys_module *) */
+    struct ly_set schema_modules;
+
+    /* options to parse and print schema modules */
+    uint32_t schema_parse_options;
+    uint32_t schema_print_options;
+
+    /* specification of printing schema node subtree, option --schema-node */
+    const char *schema_node_path;
+    const struct lysc_node *schema_node;
+    const char *submodule;
+
+    /* name of file containing explicit context passed to callback
+     * for schema-mount extension.  This also causes a callback to
+     * be registered.
+     */
+    char *schema_context_filename;
+
+    /* value of --format in case of schema format */
+    LYS_OUTFORMAT schema_out_format;
+    ly_bool feature_param_format;
+
+    /*
+     * data
+     */
+    /* various options based on --type option */
+    enum lyd_type data_type;
+    uint32_t data_parse_options;
+    uint32_t data_validate_options;
+    uint32_t data_print_options;
+
+    /* flag for --merge option */
+    uint8_t data_merge;
+
+    /* value of --format in case of data format */
+    LYD_FORMAT data_out_format;
+
+    /* input data files (struct cmdline_file *) */
+    struct ly_set data_inputs;
+
+    /* storage for --operational */
+    struct cmdline_file data_operational;
+
+    /* storage for --reply-rpc */
+    struct cmdline_file reply_rpc;
+};
+
+static void
+erase_context(struct context *c)
+{
+    /* data */
+    ly_set_erase(&c->data_inputs, free_cmdline_file);
+    ly_in_free(c->data_operational.in, 1);
+
+    /* schema */
+    ly_set_erase(&c->schema_features, free_features);
+    ly_set_erase(&c->schema_modules, NULL);
+
+    /* context */
+    free(c->searchpaths);
+    c->searchpaths = NULL;
+
+    ly_out_free(c->out, NULL,  0);
+    ly_ctx_destroy(c->ctx);
+
+    if (c->schema_context_filename) {
+        free(c->schema_context_filename);
+    }
+}
+
+static void
+version(void)
+{
+    printf("yanglint %s\n", PROJECT_VERSION);
+}
+
+static void
+help(int shortout)
+{
+
+    printf("Example usage:\n"
+            "    yanglint [-f { yang | yin | info}] <schema>...\n"
+            "        Validates the YANG module <schema>(s) and all its dependencies, optionally printing\n"
+            "        them in the specified format.\n\n"
+            "    yanglint [-f { xml | json }] <schema>... <file>...\n"
+            "        Validates the YANG modeled data <file>(s) according to the <schema>(s) optionally\n"
+            "        printing them in the specified format.\n\n"
+            "    yanglint -t (nc-)rpc/notif [-O <operational-file>] <schema>... <file>\n"
+            "        Validates the YANG/NETCONF RPC/notification <file> according to the <schema>(s) using\n"
+            "        <operational-file> with possible references to the operational datastore data.\n\n"
+            "    yanglint -t nc-reply -R <rpc-file> [-O <operational-file>] <schema>... <file>\n"
+            "        Validates the NETCONF rpc-reply <file> of RPC <rpc-file> according to the <schema>(s)\n"
+            "        using <operational-file> with possible references to the operational datastore data.\n\n"
+            "    yanglint\n"
+            "        Starts interactive mode with more features.\n\n");
+
+    if (shortout) {
+        return;
+    }
+    printf("Options:\n"
+            "  -h, --help    Show this help message and exit.\n"
+            "  -v, --version Show version number and exit.\n"
+            "  -V, --verbose Increase libyang verbosity and show verbose messages. If specified\n"
+            "                a second time, show even debug messages.\n"
+            "  -Q, --quiet   Decrease libyang verbosity and hide warnings. If specified a second\n"
+            "                time, hide errors so no libyang messages are printed.\n");
+
+    printf("  -f FORMAT, --format=FORMAT\n"
+            "                Convert input into FORMAT. Supported formats: \n"
+            "                yang, yin, tree, info and feature-param for schemas,\n"
+            "                xml, json, and lyb for data.\n\n");
+
+    printf("  -p PATH, --path=PATH\n"
+            "                Search path for schema (YANG/YIN) modules. The option can be\n"
+            "                used multiple times. The current working directory and the\n"
+            "                path of the module being added is used implicitly.\n\n");
+
+    printf("  -D, --disable-searchdir\n"
+            "                Do not implicitly search in current working directory for\n"
+            "                schema modules. If specified a second time, do not even\n"
+            "                search in the module directory (all modules must be \n"
+            "                explicitly specified).\n\n");
+
+    printf("  -F FEATURES, --features=FEATURES\n"
+            "                Specific module features to support in the form <module-name>:(<feature>,)*\n"
+            "                Use <feature> '*' to enable all features of a module. This option can be\n"
+            "                specified multiple times, to enable features in multiple modules. If this\n"
+            "                option is not specified, all the features in all the implemented modules\n"
+            "                are enabled.\n\n");
+
+    printf("  -i, --make-implemented\n"
+            "                Make the imported modules \"referenced\" from any loaded\n"
+            "                module also implemented. If specified a second time, all the\n"
+            "                modules are set implemented.\n\n");
+
+    printf("  -P PATH, --schema-node=PATH\n"
+            "                Print only the specified subtree of the schema.\n"
+            "                The PATH is the XPath subset mentioned in documentation as\n"
+            "                the Path format. The option can be combined with --single-node\n"
+            "                option to print information only about the specified node.\n"
+            "  -q, --single-node\n"
+            "                Supplement to the --schema-node option to print information\n"
+            "                only about a single node specified as PATH argument.\n\n");
+
+    printf("  -s SUBMODULE, --submodule=SUBMODULE\n"
+            "                Print the specific submodule instead of the main module.\n\n");
+
+    printf("  -x FILE, --ext-data=FILE\n"
+            "                File containing the specific data required by an extension. Required by\n"
+            "                the schema-mount extension, for example, when the operational data are\n"
+            "                expected in the file. File format is guessed.\n\n");
+
+    printf("  -n, --not-strict\n"
+            "                Do not require strict data parsing (silently skip unknown data),\n"
+            "                has no effect for schemas.\n\n");
+
+    printf("  -e, --present Validate only with the schema modules whose data actually\n"
+            "                exist in the provided input data files. Takes effect only\n"
+            "                with the 'data' or 'config' TYPEs. Used to avoid requiring\n"
+            "                mandatory nodes from modules which data are not present in the\n"
+            "                provided input data files.\n\n");
+
+    printf("  -t TYPE, --type=TYPE\n"
+            "                Specify data tree type in the input data file(s):\n"
+            "        data          - Complete datastore with status data (default type).\n"
+            "        config        - Configuration datastore (without status data).\n"
+            "        get           - Data returned by the NETCONF <get> operation.\n"
+            "        getconfig     - Data returned by the NETCONF <get-config> operation.\n"
+            "        edit          - Config content of the NETCONF <edit-config> operation.\n"
+            "        rpc           - Invocation of a YANG RPC/action, defined as input.\n"
+            "        nc-rpc        - Similar to 'rpc' but expect and check also the NETCONF\n"
+            "                        envelopes <rpc> or <action>.\n"
+            "        reply         - Reply to a YANG RPC/action, defined as output. Note that\n"
+            "                        the reply data are expected inside a container representing\n"
+            "                        the original RPC/action invocation.\n"
+            "        nc-reply      - Similar to 'reply' but expect and check also the NETCONF\n"
+            "                        envelope <rpc-reply> with output data nodes as direct\n"
+            "                        descendants. The original RPC/action invocation is expected\n"
+            "                        in a separate parameter '-R' and is parsed as 'nc-rpc'.\n"
+            "        notif         - Notification instance of a YANG notification.\n"
+            "        nc-notif      - Similar to 'notif' but expect and check also the NETCONF\n"
+            "                        envelope <notification> with element <eventTime> and its\n"
+            "                        sibling as the actual notification.\n\n");
+
+    printf("  -d MODE, --default=MODE\n"
+            "                Print data with default values, according to the MODE\n"
+            "                (to print attributes, ietf-netconf-with-defaults model\n"
+            "                must be loaded):\n"
+            "      all             - Add missing default nodes.\n"
+            "      all-tagged      - Add missing default nodes and mark all the default\n"
+            "                        nodes with the attribute.\n"
+            "      trim            - Remove all nodes with a default value.\n"
+            "      implicit-tagged - Add missing nodes and mark them with the attribute.\n\n");
+
+    printf("  -l, --list    Print info about the loaded schemas.\n"
+            "                (i - imported module, I - implemented module)\n"
+            "                In case the '-f' option with data encoding is specified,\n"
+            "                the list is printed as \"ietf-yang-library\" data.\n\n");
+
+    printf("  -L LINE_LENGTH, --tree-line-length=LINE_LENGTH\n"
+            "                The limit of the maximum line length on which the 'tree'\n"
+            "                format will try to be printed.\n\n");
+
+    printf("  -o OUTFILE, --output=OUTFILE\n"
+            "                Write the output to OUTFILE instead of stdout.\n\n");
+
+    printf("  -O FILE, --operational=FILE\n"
+            "                Provide optional data to extend validation of the '(nc-)rpc',\n"
+            "                '(nc-)reply' or '(nc-)notif' TYPEs. The FILE is supposed to contain\n"
+            "                the operational datastore referenced from the operation.\n"
+            "                In case of a nested operation, its parent existence is also\n"
+            "                checked in these operational data.\n\n");
+
+    printf("  -R FILE, --reply-rpc=FILE\n"
+            "                Provide source RPC for parsing of the 'nc-reply' TYPE. The FILE\n"
+            "                is supposed to contain the source 'nc-rpc' operation of the reply.\n\n");
+
+    printf("  -m, --merge   Merge input data files into a single tree and validate at\n"
+            "                once. The option has effect only for 'data' and 'config' TYPEs.\n\n");
+
+    printf("  -y, --yang-library\n"
+            "                Load and implement internal \"ietf-yang-library\" YANG module.\n"
+            "                Note that this module includes definitions of mandatory state\n"
+            "                data that can result in unexpected data validation errors.\n\n");
+
+    printf("  -Y FILE, --yang-library-file=FILE\n"
+            "                Parse FILE with \"ietf-yang-library\" data and use them to\n"
+            "                create an exact YANG schema context. If specified, the '-F'\n"
+            "                parameter (enabled features) is ignored.\n\n");
+
+#ifndef NDEBUG
+    printf("  -G GROUPS, --debug=GROUPS\n"
+            "                Enable printing of specific debugging message group\n"
+            "                (nothing will be printed unless verbosity is set to debug):\n"
+            "                <group>[,<group>]* (dict, xpath, dep-sets)\n\n");
+#endif
+}
+
+static void
+libyang_verbclb(LY_LOG_LEVEL level, const char *msg, const char *path)
+{
+    char *levstr;
+
+    switch (level) {
+    case LY_LLERR:
+        levstr = "err :";
+        break;
+    case LY_LLWRN:
+        levstr = "warn:";
+        break;
+    case LY_LLVRB:
+        levstr = "verb:";
+        break;
+    default:
+        levstr = "dbg :";
+        break;
+    }
+    if (path) {
+        fprintf(stderr, "libyang %s %s (%s)\n", levstr, msg, path);
+    } else {
+        fprintf(stderr, "libyang %s %s\n", levstr, msg);
+    }
+}
+
+static struct schema_features *
+get_features_not_applied(const struct ly_set *fset)
+{
+    for (uint32_t u = 0; u < fset->count; ++u) {
+        struct schema_features *sf = fset->objs[u];
+
+        if (!sf->applied) {
+            return sf;
+        }
+    }
+
+    return NULL;
+}
+
+static LY_ERR
+ext_data_clb(const struct lysc_ext_instance *ext, void *user_data, void **ext_data, ly_bool *ext_data_free)
+{
+    struct ly_ctx *ctx;
+    struct lyd_node *data = NULL;
+
+    ctx = ext->module->ctx;
+    if (user_data) {
+        lyd_parse_data_path(ctx, user_data, LYD_XML, LYD_PARSE_STRICT, LYD_VALIDATE_PRESENT, &data);
+    }
+
+    *ext_data = data;
+    *ext_data_free = 1;
+    return LY_SUCCESS;
+}
+
+static LY_ERR
+searchpath_strcat(char **searchpaths, const char *path)
+{
+    uint64_t len;
+    char *new;
+
+    if (!(*searchpaths)) {
+        *searchpaths = strdup(path);
+        return LY_SUCCESS;
+    }
+
+    len = strlen(*searchpaths) + strlen(path) + strlen(PATH_SEPARATOR);
+    new = realloc(*searchpaths, sizeof(char) * len + 1);
+    if (!new) {
+        return LY_EMEM;
+    }
+    strcat(new, PATH_SEPARATOR);
+    strcat(new, path);
+    *searchpaths = new;
+
+    return LY_SUCCESS;
+}
+
+static int
+fill_context_inputs(int argc, char *argv[], struct context *c)
+{
+    struct ly_in *in = NULL;
+    struct schema_features *sf;
+    struct lys_module *mod;
+    const char *all_features[] = {"*", NULL};
+    char *dir = NULL, *module = NULL;
+
+    /* Create libyang context. */
+    if (c->yang_lib_file) {
+        /* ignore features */
+        ly_set_erase(&c->schema_features, free_features);
+
+        if (ly_ctx_new_ylpath(c->searchpaths, c->yang_lib_file, LYD_UNKNOWN, c->ctx_options, &c->ctx)) {
+            YLMSG_E("Unable to modify libyang context with yang-library data.\n");
+            return -1;
+        }
+    } else {
+        /* set imp feature flag if all should be enabled */
+        c->ctx_options |= !c->schema_features.count ? LY_CTX_ENABLE_IMP_FEATURES : 0;
+
+        if (ly_ctx_new(c->searchpaths, c->ctx_options, &c->ctx)) {
+            YLMSG_E("Unable to create libyang context\n");
+            return -1;
+        }
+    }
+
+    /* set callback providing run-time extension instance data */
+    if (c->schema_context_filename) {
+        ly_ctx_set_ext_data_clb(c->ctx, ext_data_clb, c->schema_context_filename);
+    }
+
+    /* process the operational and/or reply RPC content if any */
+    if (c->data_operational.path) {
+        if (get_input(c->data_operational.path, NULL, &c->data_operational.format, &c->data_operational.in)) {
+            return -1;
+        }
+    }
+    if (c->reply_rpc.path) {
+        if (get_input(c->reply_rpc.path, NULL, &c->reply_rpc.format, &c->reply_rpc.in)) {
+            return -1;
+        }
+    }
+
+    for (int i = 0; i < argc - optind; i++) {
+        LYS_INFORMAT format_schema = LYS_IN_UNKNOWN;
+        LYD_FORMAT format_data = LYD_UNKNOWN;
+
+        if (get_input(argv[optind + i], &format_schema, &format_data, &in)) {
+            goto error;
+        }
+
+        if (format_schema) {
+            LY_ERR ret;
+            uint8_t path_unset = 1; /* flag to unset the path from the searchpaths list (if not already present) */
+            const char **features;
+
+            /* parse the input */
+            if (parse_schema_path(argv[optind + i], &dir, &module)) {
+                goto error;
+            }
+
+            if (c->yang_lib_file) {
+                /* just get the module, it should already be parsed */
+                mod = ly_ctx_get_module_implemented(c->ctx, module);
+                if (!mod) {
+                    YLMSG_E("Schema module \"%s\" not implemented in yang-library data.\n", module);
+                    goto error;
+                }
+            } else {
+                /* add temporarily also the path of the module itself */
+                if (ly_ctx_set_searchdir(c->ctx, dir) == LY_EEXIST) {
+                    path_unset = 0;
+                }
+
+                /* get features list for this module */
+                if (!c->schema_features.count) {
+                    features = all_features;
+                } else {
+                    get_features(&c->schema_features, module, &features);
+                }
+
+                /* parse module */
+                ret = lys_parse(c->ctx, in, format_schema, features, &mod);
+                ly_ctx_unset_searchdir_last(c->ctx, path_unset);
+                if (ret) {
+                    YLMSG_E("Parsing schema module \"%s\" failed.\n", argv[optind + i]);
+                    goto error;
+                }
+            }
+
+            /* temporary cleanup */
+            free(dir);
+            dir = NULL;
+            free(module);
+            module = NULL;
+
+            if (c->schema_out_format || c->feature_param_format) {
+                /* module will be printed */
+                if (ly_set_add(&c->schema_modules, (void *)mod, 1, NULL)) {
+                    YLMSG_E("Storing parsed schema module (%s) for print failed.\n", argv[optind + i]);
+                    goto error;
+                }
+            }
+        } else if (format_data) {
+            if (!fill_cmdline_file(&c->data_inputs, in, argv[optind + i], format_data)) {
+                goto error;
+            }
+            in = NULL;
+        }
+
+        ly_in_free(in, 1);
+        in = NULL;
+    }
+
+    /* check that all specified features were applied, apply now if possible */
+    while ((sf = get_features_not_applied(&c->schema_features))) {
+        /* try to find implemented or the latest revision of this module */
+        mod = ly_ctx_get_module_implemented(c->ctx, sf->mod_name);
+        if (!mod) {
+            mod = ly_ctx_get_module_latest(c->ctx, sf->mod_name);
+        }
+        if (!mod) {
+            YLMSG_E("Specified features not applied, module \"%s\" not loaded.\n", sf->mod_name);
+            goto error;
+        }
+
+        /* we have the module, implement it if needed and enable the specific features */
+        if (lys_set_implemented(mod, (const char **)sf->features)) {
+            YLMSG_E("Implementing module \"%s\" failed.\n", mod->name);
+            goto error;
+        }
+        sf->applied = 1;
+    }
+
+    return 0;
+
+error:
+    ly_in_free(in, 1);
+    free(dir);
+    free(module);
+    return -1;
+}
+
+/**
+ * @brief Process command line options and store the settings into the context.
+ *
+ * return -1 in case of error;
+ * return 0 in case of success and ready to process
+ * return 1 in case of success, but expect to exit.
+ */
+static int
+fill_context(int argc, char *argv[], struct context *c)
+{
+    int ret;
+
+    int opt, opt_index;
+    struct option options[] = {
+        {"help",              no_argument,       NULL, 'h'},
+        {"version",           no_argument,       NULL, 'v'},
+        {"verbose",           no_argument,       NULL, 'V'},
+        {"quiet",             no_argument,       NULL, 'Q'},
+        {"format",            required_argument, NULL, 'f'},
+        {"path",              required_argument, NULL, 'p'},
+        {"disable-searchdir", no_argument,       NULL, 'D'},
+        {"features",          required_argument, NULL, 'F'},
+        {"make-implemented",  no_argument,       NULL, 'i'},
+        {"schema-node",       required_argument, NULL, 'P'},
+        {"single-node",       no_argument,       NULL, 'q'},
+        {"submodule",         required_argument, NULL, 's'},
+        {"ext-data",          required_argument, NULL, 'x'},
+        {"not-strict",        no_argument,       NULL, 'n'},
+        {"present",           no_argument,       NULL, 'e'},
+        {"type",              required_argument, NULL, 't'},
+        {"default",           required_argument, NULL, 'd'},
+        {"list",              no_argument,       NULL, 'l'},
+        {"tree-line-length",  required_argument, NULL, 'L'},
+        {"output",            required_argument, NULL, 'o'},
+        {"operational",       required_argument, NULL, 'O'},
+        {"reply-rpc",         required_argument, NULL, 'R'},
+        {"merge",             no_argument,       NULL, 'm'},
+        {"yang-library",      no_argument,       NULL, 'y'},
+        {"yang-library-file", required_argument, NULL, 'Y'},
+#ifndef NDEBUG
+        {"debug",            required_argument, NULL, 'G'},
+#endif
+        {NULL,               0,                 NULL, 0}
+    };
+    uint8_t data_type_set = 0;
+
+    c->ctx_options = YL_DEFAULT_CTX_OPTIONS;
+    c->data_parse_options = YL_DEFAULT_DATA_PARSE_OPTIONS;
+    c->line_length = 0;
+
+    opterr = 0;
+#ifndef NDEBUG
+    while ((opt = getopt_long(argc, argv, "hvVQf:p:DF:iP:qs:net:d:lL:o:O:R:myY:x:G:", options, &opt_index)) != -1)
+#else
+    while ((opt = getopt_long(argc, argv, "hvVQf:p:DF:iP:qs:net:d:lL:o:O:R:myY:x:", options, &opt_index)) != -1)
+#endif
+    {
+        switch (opt) {
+        case 'h': /* --help */
+            help(0);
+            return 1;
+
+        case 'v': /* --version */
+            version();
+            return 1;
+
+        case 'V': { /* --verbose */
+            LY_LOG_LEVEL verbosity = ly_log_level(LY_LLERR);
+
+            if (verbosity < LY_LLDBG) {
+                ++verbosity;
+            }
+            ly_log_level(verbosity);
+            break;
+        } /* case 'V' */
+
+        case 'Q': { /* --quiet */
+            LY_LOG_LEVEL verbosity = ly_log_level(LY_LLERR);
+
+            if (verbosity == LY_LLERR) {
+                /* turn logging off */
+                ly_log_options(LY_LOSTORE_LAST);
+            } else if (verbosity > LY_LLERR) {
+                --verbosity;
+            }
+            ly_log_level(verbosity);
+            break;
+        } /* case 'Q' */
+
+        case 'f': /* --format */
+            if (!strcasecmp(optarg, "yang")) {
+                c->schema_out_format = LYS_OUT_YANG;
+                c->data_out_format = 0;
+            } else if (!strcasecmp(optarg, "yin")) {
+                c->schema_out_format = LYS_OUT_YIN;
+                c->data_out_format = 0;
+            } else if (!strcasecmp(optarg, "info")) {
+                c->schema_out_format = LYS_OUT_YANG_COMPILED;
+                c->data_out_format = 0;
+            } else if (!strcasecmp(optarg, "tree")) {
+                c->schema_out_format = LYS_OUT_TREE;
+                c->data_out_format = 0;
+            } else if (!strcasecmp(optarg, "xml")) {
+                c->schema_out_format = 0;
+                c->data_out_format = LYD_XML;
+            } else if (!strcasecmp(optarg, "json")) {
+                c->schema_out_format = 0;
+                c->data_out_format = LYD_JSON;
+            } else if (!strcasecmp(optarg, "lyb")) {
+                c->schema_out_format = 0;
+                c->data_out_format = LYD_LYB;
+            } else if (!strcasecmp(optarg, "feature-param")) {
+                c->feature_param_format = 1;
+            } else {
+                YLMSG_E("Unknown output format %s\n", optarg);
+                help(1);
+                return -1;
+            }
+            break;
+
+        case 'p': { /* --path */
+            struct stat st;
+
+            if (stat(optarg, &st) == -1) {
+                YLMSG_E("Unable to use search path (%s) - %s.\n", optarg, strerror(errno));
+                return -1;
+            }
+            if (!S_ISDIR(st.st_mode)) {
+                YLMSG_E("Provided search path is not a directory.\n");
+                return -1;
+            }
+
+            if (searchpath_strcat(&c->searchpaths, optarg)) {
+                YLMSG_E("Storing searchpath failed.\n");
+                return -1;
+            }
+
+            break;
+        } /* case 'p' */
+
+        case 'D': /* --disable-search */
+            if (c->ctx_options & LY_CTX_DISABLE_SEARCHDIRS) {
+                YLMSG_W("The -D option specified too many times.\n");
+            }
+            if (c->ctx_options & LY_CTX_DISABLE_SEARCHDIR_CWD) {
+                c->ctx_options &= ~LY_CTX_DISABLE_SEARCHDIR_CWD;
+                c->ctx_options |= LY_CTX_DISABLE_SEARCHDIRS;
+            } else {
+                c->ctx_options |= LY_CTX_DISABLE_SEARCHDIR_CWD;
+            }
+            break;
+
+        case 'F': /* --features */
+            if (parse_features(optarg, &c->schema_features)) {
+                return -1;
+            }
+            break;
+
+        case 'i': /* --make-implemented */
+            if (c->ctx_options & LY_CTX_REF_IMPLEMENTED) {
+                c->ctx_options &= ~LY_CTX_REF_IMPLEMENTED;
+                c->ctx_options |= LY_CTX_ALL_IMPLEMENTED;
+            } else {
+                c->ctx_options |= LY_CTX_REF_IMPLEMENTED;
+            }
+            break;
+
+        case 'P': /* --schema-node */
+            c->schema_node_path = optarg;
+            break;
+
+        case 'q': /* --single-node */
+            c->schema_print_options |= LYS_PRINT_NO_SUBSTMT;
+            break;
+
+        case 's': /* --submodule */
+            c->submodule = optarg;
+            break;
+
+        case 'x': /* --ext-data */
+            c->schema_context_filename = strdup(optarg);
+            break;
+
+        case 'n': /* --not-strict */
+            c->data_parse_options &= ~LYD_PARSE_STRICT;
+            break;
+
+        case 'e': /* --present */
+            c->data_validate_options |= LYD_VALIDATE_PRESENT;
+            break;
+
+        case 't': /* --type */
+            if (data_type_set) {
+                YLMSG_E("The data type (-t) cannot be set multiple times.\n");
+                return -1;
+            }
+
+            if (!strcasecmp(optarg, "config")) {
+                c->data_parse_options |= LYD_PARSE_NO_STATE;
+                c->data_validate_options |= LYD_VALIDATE_NO_STATE;
+            } else if (!strcasecmp(optarg, "get")) {
+                c->data_parse_options |= LYD_PARSE_ONLY;
+            } else if (!strcasecmp(optarg, "getconfig") || !strcasecmp(optarg, "get-config")) {
+                c->data_parse_options |= LYD_PARSE_ONLY | LYD_PARSE_NO_STATE;
+            } else if (!strcasecmp(optarg, "edit")) {
+                c->data_parse_options |= LYD_PARSE_ONLY;
+            } else if (!strcasecmp(optarg, "rpc")) {
+                c->data_type = LYD_TYPE_RPC_YANG;
+            } else if (!strcasecmp(optarg, "nc-rpc")) {
+                c->data_type = LYD_TYPE_RPC_NETCONF;
+            } else if (!strcasecmp(optarg, "reply")) {
+                c->data_type = LYD_TYPE_REPLY_YANG;
+            } else if (!strcasecmp(optarg, "nc-reply")) {
+                c->data_type = LYD_TYPE_REPLY_NETCONF;
+            } else if (!strcasecmp(optarg, "notif")) {
+                c->data_type = LYD_TYPE_NOTIF_YANG;
+            } else if (!strcasecmp(optarg, "nc-notif")) {
+                c->data_type = LYD_TYPE_NOTIF_NETCONF;
+            } else if (!strcasecmp(optarg, "data")) {
+                /* default option */
+            } else {
+                YLMSG_E("Unknown data tree type %s\n", optarg);
+                help(1);
+                return -1;
+            }
+
+            data_type_set = 1;
+            break;
+
+        case 'd': /* --default */
+            if (!strcasecmp(optarg, "all")) {
+                c->data_print_options = (c->data_print_options & ~LYD_PRINT_WD_MASK) | LYD_PRINT_WD_ALL;
+            } else if (!strcasecmp(optarg, "all-tagged")) {
+                c->data_print_options = (c->data_print_options & ~LYD_PRINT_WD_MASK) | LYD_PRINT_WD_ALL_TAG;
+            } else if (!strcasecmp(optarg, "trim")) {
+                c->data_print_options = (c->data_print_options & ~LYD_PRINT_WD_MASK) | LYD_PRINT_WD_TRIM;
+            } else if (!strcasecmp(optarg, "implicit-tagged")) {
+                c->data_print_options = (c->data_print_options & ~LYD_PRINT_WD_MASK) | LYD_PRINT_WD_IMPL_TAG;
+            } else {
+                YLMSG_E("Unknown default mode %s\n", optarg);
+                help(1);
+                return -1;
+            }
+            break;
+
+        case 'l': /* --list */
+            c->list = 1;
+            break;
+
+        case 'L': /* --tree-line-length */
+            c->line_length = atoi(optarg);
+            break;
+
+        case 'o': /* --output */
+            if (c->out) {
+                YLMSG_E("Only a single output can be specified.\n");
+                return -1;
+            } else {
+                if (ly_out_new_filepath(optarg, &c->out)) {
+                    YLMSG_E("Unable open output file %s (%s)\n", optarg, strerror(errno));
+                    return -1;
+                }
+            }
+            break;
+
+        case 'O': /* --operational */
+            if (c->data_operational.path) {
+                YLMSG_E("The operational datastore (-O) cannot be set multiple times.\n");
+                return -1;
+            }
+            c->data_operational.path = optarg;
+            break;
+
+        case 'R': /* --reply-rpc */
+            if (c->reply_rpc.path) {
+                YLMSG_E("The PRC of the reply (-R) cannot be set multiple times.\n");
+                return -1;
+            }
+            c->reply_rpc.path = optarg;
+            break;
+
+        case 'm': /* --merge */
+            c->data_merge = 1;
+            break;
+
+        case 'y': /* --yang-library */
+            c->ctx_options &= ~LY_CTX_NO_YANGLIBRARY;
+            break;
+
+        case 'Y': /* --yang-library-file */
+            c->ctx_options &= ~LY_CTX_NO_YANGLIBRARY;
+            c->yang_lib_file = optarg;
+            break;
+
+#ifndef NDEBUG
+        case 'G': { /* --debug */
+            uint32_t dbg_groups = 0;
+            const char *ptr = optarg;
+
+            while (ptr[0]) {
+                if (!strncasecmp(ptr, "dict", sizeof "dict" - 1)) {
+                    dbg_groups |= LY_LDGDICT;
+                    ptr += sizeof "dict" - 1;
+                } else if (!strncasecmp(ptr, "xpath", sizeof "xpath" - 1)) {
+                    dbg_groups |= LY_LDGXPATH;
+                    ptr += sizeof "xpath" - 1;
+                } else if (!strncasecmp(ptr, "dep-sets", sizeof "dep-sets" - 1)) {
+                    dbg_groups |= LY_LDGDEPSETS;
+                    ptr += sizeof "dep-sets" - 1;
+                }
+
+                if (ptr[0]) {
+                    if (ptr[0] != ',') {
+                        YLMSG_E("Unknown debug group string \"%s\"\n", optarg);
+                        return -1;
+                    }
+                    ++ptr;
+                }
+            }
+            ly_log_dbg_groups(dbg_groups);
+            break;
+        } /* case 'G' */
+#endif
+        default:
+            YLMSG_E("Invalid option or missing argument: -%c\n", optopt);
+            return -1;
+        } /* switch */
+    }
+
+    /* additional checks for the options combinations */
+    if (!c->list && (optind >= argc)) {
+        help(1);
+        YLMSG_E("Missing <schema> to process.\n");
+        return 1;
+    }
+
+    if (c->data_merge) {
+        if (c->data_type || (c->data_parse_options & LYD_PARSE_ONLY)) {
+            /* switch off the option, incompatible input data type */
+            c->data_merge = 0;
+        } else {
+            /* postpone validation after the merge of all the input data */
+            c->data_parse_options |= LYD_PARSE_ONLY;
+        }
+    }
+
+    if (c->data_operational.path && !c->data_type) {
+        YLMSG_E("Operational datastore takes effect only with RPCs/Actions/Replies/Notification input data types.\n");
+        c->data_operational.path = NULL;
+    }
+
+    if (c->reply_rpc.path && (c->data_type != LYD_TYPE_REPLY_NETCONF)) {
+        YLMSG_E("Source RPC is needed only for NETCONF Reply input data type.\n");
+        c->data_operational.path = NULL;
+    } else if (!c->reply_rpc.path && (c->data_type == LYD_TYPE_REPLY_NETCONF)) {
+        YLMSG_E("Missing source RPC (-R) for NETCONF Reply input data type.\n");
+        return -1;
+    }
+
+    if ((c->schema_out_format != LYS_OUT_TREE) && c->line_length) {
+        YLMSG_E("--tree-line-length take effect only in case of the tree output format.\n");
+    }
+
+    /* default output stream */
+    if (!c->out) {
+        if (ly_out_new_file(stdout, &c->out)) {
+            YLMSG_E("Unable to set stdout as output.\n");
+            return -1;
+        }
+    }
+
+    if (c->schema_out_format == LYS_OUT_TREE) {
+        /* print tree from lysc_nodes */
+        c->ctx_options |= LY_CTX_SET_PRIV_PARSED;
+    }
+
+    /* process input files provided as standalone command line arguments,
+     * schema modules are parsed and inserted into the context,
+     * data files are just checked and prepared into internal structures for further processing */
+    ret = fill_context_inputs(argc, argv, c);
+    if (ret) {
+        return ret;
+    }
+
+    /* the second batch of checks */
+    if (c->schema_print_options && !c->schema_out_format) {
+        YLMSG_W("Schema printer options specified, but the schema output format is missing.\n");
+    }
+    if (c->schema_parse_options && !c->schema_modules.count) {
+        YLMSG_W("Schema parser options specified, but no schema input file provided.\n");
+    }
+    if (c->data_print_options && !c->data_out_format) {
+        YLMSG_W("data printer options specified, but the data output format is missing.\n");
+    }
+    if (((c->data_parse_options != YL_DEFAULT_DATA_PARSE_OPTIONS) || c->data_type) && !c->data_inputs.count) {
+        YLMSG_W("Data parser options specified, but no data input file provided.\n");
+    }
+
+    if (c->schema_node_path) {
+        c->schema_node = lys_find_path(c->ctx, NULL, c->schema_node_path, 0);
+        if (!c->schema_node) {
+            c->schema_node = lys_find_path(c->ctx, NULL, c->schema_node_path, 1);
+
+            if (!c->schema_node) {
+                YLMSG_E("Invalid schema path.\n");
+                return -1;
+            }
+        }
+    }
+
+    return 0;
+}
+
+int
+main_ni(int argc, char *argv[])
+{
+    int ret = EXIT_SUCCESS, r;
+    struct context c = {0};
+    char *features_output = NULL;
+    struct ly_set set = {0};
+    uint32_t u;
+
+    /* set callback for printing libyang messages */
+    ly_set_log_clb(libyang_verbclb, 1);
+
+    r = fill_context(argc, argv, &c);
+    if (r < 0) {
+        ret = EXIT_FAILURE;
+    }
+    if (r) {
+        goto cleanup;
+    }
+
+    /* do the required job - parse, validate, print */
+
+    if (c.list) {
+        /* print the list of schemas */
+        print_list(c.out, c.ctx, c.data_out_format);
+    } else {
+        if (c.feature_param_format) {
+            for (u = 0; u < c.schema_modules.count; u++) {
+                if (collect_features(c.schema_modules.objs[u], &set)) {
+                    YLMSG_E("Unable to read features from a module.\n");
+                    goto cleanup;
+                }
+                if (generate_features_output(c.schema_modules.objs[u], &set, &features_output)) {
+                    YLMSG_E("Unable to generate feature command output.\n");
+                    goto cleanup;
+                }
+                ly_set_erase(&set, NULL);
+            }
+            ly_print(c.out, "%s\n", features_output);
+        } else if (c.schema_out_format) {
+            if (c.schema_node) {
+                ret = lys_print_node(c.out, c.schema_node, c.schema_out_format, 0, c.schema_print_options);
+                if (ret) {
+                    YLMSG_E("Unable to print schema node %s.\n", c.schema_node_path);
+                    goto cleanup;
+                }
+            } else if (c.submodule) {
+                const struct lysp_submodule *submod = ly_ctx_get_submodule_latest(c.ctx, c.submodule);
+
+                if (!submod) {
+                    YLMSG_E("Unable to find submodule %s.\n", c.submodule);
+                    goto cleanup;
+                }
+
+                ret = lys_print_submodule(c.out, submod, c.schema_out_format, c.line_length, c.schema_print_options);
+                if (ret) {
+                    YLMSG_E("Unable to print submodule %s.\n", submod->name);
+                    goto cleanup;
+                }
+            } else {
+                for (u = 0; u < c.schema_modules.count; ++u) {
+                    ret = lys_print_module(c.out, (struct lys_module *)c.schema_modules.objs[u], c.schema_out_format,
+                            c.line_length, c.schema_print_options);
+                    /* for YANG Tree Diagrams printing it's more readable to print a blank line between modules. */
+                    if ((c.schema_out_format == LYS_OUT_TREE) && (u + 1 < c.schema_modules.count)) {
+                        ly_print(c.out, "\n");
+                    }
+                    if (ret) {
+                        YLMSG_E("Unable to print module %s.\n", ((struct lys_module *)c.schema_modules.objs[u])->name);
+                        goto cleanup;
+                    }
+                }
+            }
+        }
+
+        /* do the data validation despite the schema was printed */
+        if (c.data_inputs.size) {
+            ret = process_data(c.ctx, c.data_type, c.data_merge, c.data_out_format, c.out, c.data_parse_options,
+                    c.data_validate_options, c.data_print_options, &c.data_operational, &c.reply_rpc, &c.data_inputs, NULL);
+            if (ret) {
+                goto cleanup;
+            }
+        }
+    }
+
+cleanup:
+    /* cleanup */
+    erase_context(&c);
+    free(features_output);
+    ly_set_erase(&set, NULL);
+
+    return ret;
+}
diff --git a/tools/lint/main_ni_only.c b/tools/lint/main_ni_only.c
new file mode 100644
index 0000000..d55f2c2
--- /dev/null
+++ b/tools/lint/main_ni_only.c
@@ -0,0 +1,22 @@
+/**
+ * @file main_ni_only.c
+ * @brief non-interactive implementation of main() for those platforms without the linenoise library
+ *
+ * Copyright (c) 2015-2021 CESNET, z.s.p.o.
+ *
+ * This source code is licensed under BSD 3-Clause License (the "License").
+ * You may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://opensource.org/licenses/BSD-3-Clause
+ */
+
+int main_ni(int argc, char *argv[]);
+
+int done; /* for cmd.c */
+
+int
+main(int argc, char *argv[])
+{
+    return main_ni(argc, argv);
+}
diff --git a/tools/lint/tests/expect/common.exp b/tools/lint/tests/expect/common.exp
new file mode 100644
index 0000000..0381e6c
--- /dev/null
+++ b/tools/lint/tests/expect/common.exp
@@ -0,0 +1,68 @@
+# detect the path to the yanglint binary
+if { [info exists ::env(YANGLINT)] } {
+    set yanglint "$env(YANGLINT)"
+} else {
+    set yanglint "../../../../build/yanglint"
+}
+
+# set the timeout to 1 second
+set timeout 1
+
+# expect a single line of anchored regex output
+proc expect_output {output} {
+    expect {
+        -re "^${output}$" {}
+        timeout {exit 1}
+    }
+}
+
+# send a command and either expect some anchored regex output if specified or just an empty line
+proc expect_command {command has_output output} {
+    send -- "${command}\r"
+
+    if ($has_output==1) {
+        expect {
+            -re "^${command}\r\n${output}$" {}
+            timeout {exit 1}
+        }
+    } else {
+        # input echoes
+        expect {
+            -re "^${command}\r\n$" {}
+            timeout {exit 1}
+        }
+        expect {
+            -re "^> $" {}
+            timeout {exit 1}
+        }
+    }
+}
+
+# send a completion request and check if the anchored regex output matches
+proc expect_completion {input output} {
+    send -- "${input}\t"
+
+    expect {
+        # expecting echoing input, output and 10 terminal control characters
+        -re "^${input}\r> ${output}.*\r.*$" {}
+        timeout {exit 1}
+    }
+}
+
+# send a completion request and check if the anchored regex hint options match
+proc expect_hint {input prev_input hints} {
+    set output {}
+    foreach i $hints {
+        # each element might have some number of spaces and CRLF around it
+        append output "${i} *(?:\\r\\n)?"
+    }
+
+    send -- "${input}\t"
+
+    expect {
+        # expecting the hints, previous input from which the hints were generated
+        # and some number of terminal control characters
+        -re "^\r\n${output}\r> ${prev_input}.*\r.*$" {}
+        timeout {exit 1}
+    }
+}
diff --git a/tools/lint/tests/expect/completion.exp b/tools/lint/tests/expect/completion.exp
new file mode 100755
index 0000000..ed4f6bd
--- /dev/null
+++ b/tools/lint/tests/expect/completion.exp
@@ -0,0 +1,60 @@
+#!/usr/bin/expect -f
+
+if { [info exists ::env(CURRENT_SOURCE_DIR)] } {
+    source "$env(CURRENT_SOURCE_DIR)/tests/expect/common.exp"
+    set yang_dir "$env(CURRENT_SOURCE_DIR)/examples"
+} else {
+    source "common.exp"
+    set yang_dir "../../examples"
+}
+
+spawn $yanglint
+
+# skip no dir and/or no history warnings
+expect_output "(YANGLINT.*)*> "
+
+expect_command "clear -ii" 0 ""
+
+expect_command "add ${yang_dir}/ietf-ip.yang" 0 ""
+
+expect_completion "print -f info -P " "print -f info -P /ietf-"
+
+set hints {"/ietf-yang-schema-mount:schema-mounts" "/ietf-interfaces:interfaces" "/ietf-interfaces:interfaces-state"}
+
+expect_hint "" "print -f info -P /ietf-" $hints
+
+expect_completion "i" "print -f info -P /ietf-interfaces:interfaces"
+
+expect_completion "/" "print -f info -P /ietf-interfaces:interfaces/interface"
+
+set hints {"/ietf-interfaces:interfaces/interface"
+"/ietf-interfaces:interfaces/interface/name" "/ietf-interfaces:interfaces/interface/description"
+"/ietf-interfaces:interfaces/interface/type" "/ietf-interfaces:interfaces/interface/enabled"
+"/ietf-interfaces:interfaces/interface/link-up-down-trap-enable"
+"/ietf-interfaces:interfaces/interface/ietf-ip:ipv4" "/ietf-interfaces:interfaces/interface/ietf-ip:ipv6"}
+
+expect_hint "" "print -f info -P /ietf-interfaces:interfaces/interface" $hints
+
+expect_completion "/i" "print -f info -P /ietf-interfaces:interfaces/interface/ietf-ip:ipv"
+
+expect_completion "4" "print -f info -P /ietf-interfaces:interfaces/interface/ietf-ip:ipv4"
+
+set hints { "/ietf-interfaces:interfaces/interface/ietf-ip:ipv4" "/ietf-interfaces:interfaces/interface/ietf-ip:ipv4/enabled"
+"/ietf-interfaces:interfaces/interface/ietf-ip:ipv4/forwarding" "/ietf-interfaces:interfaces/interface/ietf-ip:ipv4/mtu"
+"/ietf-interfaces:interfaces/interface/ietf-ip:ipv4/address" "/ietf-interfaces:interfaces/interface/ietf-ip:ipv4/neighbor"
+}
+
+expect_hint "\t" "print -f info -P /ietf-interfaces:interfaces/interface/ietf-ip:ipv" $hints
+
+expect_completion "/e" "print -f info -P /ietf-interfaces:interfaces/interface/ietf-ip:ipv4/enabled "
+
+send -- "\r"
+
+expect {
+    -re ".*\r\n> " {}
+    timeout {exit 1}
+}
+
+send -- "exit\r"
+
+expect eof
diff --git a/tools/lint/tests/expect/feature.exp b/tools/lint/tests/expect/feature.exp
new file mode 100755
index 0000000..37680b0
--- /dev/null
+++ b/tools/lint/tests/expect/feature.exp
@@ -0,0 +1,20 @@
+#!/usr/bin/expect -f
+
+if { [info exists ::env(CURRENT_SOURCE_DIR)] } {
+    source "$env(CURRENT_SOURCE_DIR)/tests/expect/common.exp"
+    set yang_dir "$env(CURRENT_SOURCE_DIR)/examples"
+} else {
+    source "common.exp"
+    set yang_dir "../../examples"
+}
+
+spawn $yanglint
+
+# skip no dir and/or no history warnings
+expect_output "(YANGLINT.*)*> "
+
+expect_command "feature -a" 1 "yang:\r\n\t\\(none\\)\r\n\r\nietf-yang-schema-mount:\r\n\t\\(none\\)\r\n\r\n> "
+
+send -- "exit\r"
+
+expect eof
diff --git a/tools/lint/tests/expect/list.exp b/tools/lint/tests/expect/list.exp
new file mode 100755
index 0000000..ec3cdba
--- /dev/null
+++ b/tools/lint/tests/expect/list.exp
@@ -0,0 +1,20 @@
+#!/usr/bin/expect -f
+
+if { [info exists ::env(CURRENT_SOURCE_DIR)] } {
+    source "$env(CURRENT_SOURCE_DIR)/tests/expect/common.exp"
+    set yang_dir "$env(CURRENT_SOURCE_DIR)/examples"
+} else {
+    source "common.exp"
+    set yang_dir "../../examples"
+}
+
+spawn $yanglint
+
+# skip no dir and/or no history warnings
+expect_output "(YANGLINT.*)*> "
+
+expect_command "list" 1 "List of the loaded models:\r\n *i ietf-yang-metadata@2016-08-05\r\n *I yang@2022-06-16\r\n *i ietf-inet-types@2013-07-15\r\n *i ietf-yang-types@2013-07-15\r\n *I ietf-yang-schema-mount@2019-01-14\r\n *i ietf-yang-structure-ext@2020-06-17\r\n> "
+
+send -- "exit\r"
+
+expect eof
diff --git a/tools/lint/tests/shunit2/feature.sh b/tools/lint/tests/shunit2/feature.sh
new file mode 100755
index 0000000..fb2ee88
--- /dev/null
+++ b/tools/lint/tests/shunit2/feature.sh
@@ -0,0 +1,19 @@
+#!/usr/bin/env bash
+
+testFeature() {
+	models=( "iana-if-type@2014-05-08.yang" "ietf-netconf@2011-06-01.yang" "ietf-netconf-with-defaults@2011-06-01.yang"
+	 		"sm.yang" "ietf-interfaces@2014-05-08.yang" "ietf-netconf-acm@2018-02-14.yang" "ietf-origin@2018-02-14.yang"
+	 		"ietf-ip@2014-06-16.yang" "ietf-restconf@2017-01-26.yang" )
+	features=( " -F iana-if-type:"
+			  " -F ietf-netconf:writable-running,candidate,confirmed-commit,rollback-on-error,validate,startup,url,xpath"
+			  " -F ietf-netconf-with-defaults:" " -F sm:" " -F ietf-interfaces:arbitrary-names,pre-provisioning,if-mib"
+			  " -F ietf-netconf-acm:" " -F ietf-origin:" " -F ietf-ip:ipv4-non-contiguous-netmasks,ipv6-privacy-autoconf"
+			  " -F ietf-restconf:" )
+
+	for i in ${!models[@]}; do
+		output=`${YANGLINT} -f feature-param ${YANG_MODULES_DIR}/${models[$i]}`
+		assertEquals "Unexpected features of module ${models[$i]}." "${features[$i]}" "${output}"
+	done
+}
+
+. shunit2
diff --git a/tools/lint/tests/shunit2/list.sh b/tools/lint/tests/shunit2/list.sh
new file mode 100755
index 0000000..d64503a
--- /dev/null
+++ b/tools/lint/tests/shunit2/list.sh
@@ -0,0 +1,28 @@
+#!/usr/bin/env bash
+
+LIST_BASE="List of the loaded models:
+    i ietf-yang-metadata@2016-08-05
+    I yang@2022-06-16
+    i ietf-inet-types@2013-07-15
+    i ietf-yang-types@2013-07-15
+    I ietf-yang-schema-mount@2019-01-14
+    i ietf-yang-structure-ext@2020-06-17"
+
+testListEmptyContext() {
+  output=`${YANGLINT} -l`
+  assertEquals "Unexpected list of modules in empty context." "${LIST_BASE}" "${output}"
+}
+
+testListAllImplemented() {
+  LIST_BASE_ALLIMPLEMENTED="List of the loaded models:
+    I ietf-yang-metadata@2016-08-05
+    I yang@2022-06-16
+    I ietf-inet-types@2013-07-15
+    I ietf-yang-types@2013-07-15
+    I ietf-yang-schema-mount@2019-01-14
+    I ietf-yang-structure-ext@2020-06-17"
+  output=`${YANGLINT} -lii`
+  assertEquals "Unexpected list of modules in empty context with -ii." "${LIST_BASE_ALLIMPLEMENTED}" "${output}"
+}
+
+. shunit2
diff --git a/tools/lint/yanglint.1 b/tools/lint/yanglint.1
new file mode 100644
index 0000000..4b7060d
--- /dev/null
+++ b/tools/lint/yanglint.1
@@ -0,0 +1,136 @@
+.\" Manpage for yanglint.
+.\" Process this file with
+.\" groff -man -Tascii yanglint.1
+.\"
+
+.TH YANGLINT 1 "2016-10-27" "libyang"
+.SH NAME
+yanglint \- YANG lint tool
+.
+.SH SYNOPSIS
+.B yanglint
+.br
+.B yanglint
+[\fIOPTIONS\fP]
+[\-f { \fByang\fP | \fByin\fP | \fBtree\fP } ]
+.I FILE ...
+.br
+.B yanglint
+[\fIOPTIONS\fP]
+[\-f { \fBxml\fP | \fBjson\fP } ]
+\fISCHEMA\fP...
+\fIFILE\fP...
+.
+.SH DESCRIPTION
+\fByanglint\fP is a command-line tool for validating and converting YANG
+schemas and the YANG modeled data. For a simple use, it validates the provided
+file and if the output format specified, it converts input data into the output
+format. If started with no argument, \fByanglint\fP opens interactive
+environment where the user is allowed to work with schemas and data in a more
+complex way.
+.
+.SH OPTIONS
+.TP
+.BR "\-h\fR,\fP \-\^\-help"
+Outputs usage help and exits.
+.TP
+.BR "\-v\fR,\fP \-\^\-version"
+Outputs the version number and exits.
+.TP
+.BR "\-V\fR,\fP \-\^\-verbose"
+Increases the verbosity level. If not specified, only errors are printed, with
+each appearance it adds: warnings, verbose messages, debug messages (if compiled
+with debug information).
+.TP
+.BR "\-p \fIPATH\fP\fR,\fP \-\^\-path=\fIPATH\fP"
+Specifies search path for getting imported modules or included submodules. The option
+can be used multiple times. The current working directory and path of the module
+being added is used implicitly.
+.TP
+.BR "\-s\fR,\fP \-\^\-strict"
+Changes handling of unknown data nodes - instead of silently ignoring unknown data,
+error is printed and data parsing fails. This option applies only on data parsing.
+.TP
+.BR "\-f \fIFORMAT\fP\fR,\fP \-\^\-format=\fIFORMAT\fP"
+Converts the content of the input \fIFILE\fPs into the specified \fIFORMAT\fP. If no
+\fIOUTFILE\fP is specified, the data are printed on the standard output. Only the
+compatible formats for the input \fIFILE\fPs are allowed, see the section \fBFORMATS\fP.
+.TP
+.BR "\-o \fIOUTFILE\fP\fR,\fP \-\^\-output=\fIOUTFILE\fP"
+Writes the output data into the specified \fIOUTFILE\fP. The option can be used
+only in combination with \fB--format\fR option. In case of converting schema, only
+a single input schema \fIFILE\fP is allowed. In case of data input \fIFILE\fPs,
+input is merged and printed into a single \fIOUTFILE\fP.
+.TP
+.BR "\-F \fIFEATURES\fP\fR,\fP \-\^\-features=\fIFEATURES\fP"
+Specifies the list of enabled features in the format
+\fIMODULE\fP:[\fIFEATURE\fP,...]. In case of processing multiple modules, the
+option can be used repeatedly. To disable all the features, use an empty list
+specified for the particular module.
+.TP
+.BR "\-d \fIMODE\fP\fR,\fP \-\^\-default=\fIMODE\fP"
+Print data with default values, according to the \fIMODE\fP (to print attributes,
+the ietf-netconf-with-defaults model must be loaded). The \fIMODE\fP is one of the following:
+ \[bu] \fBall\fP             - add missing default nodes
+ \[bu] \fBall-tagged\fP      - add missing default nodes and mark all the default nodes with the attribute
+ \[bu] \fBtrim\fP            - remove all nodes with a default value
+ \[bu] \fBimplicit-tagged\fP - add missing nodes and mark them with the attribute
+.TP
+.BR "\-t \fITYPE\fP\fR,\fP \-\^\-type=\fITYPE\fP"
+Specify data tree type in the input data \fIFILE\fPs. The \fITYPE\fP is one of the following:
+ \[bu] \fBauto\fP            - Resolve data type (one of the following) automatically (as pyang does). Applicable only on XML input data.
+ \[bu] \fBdata\fP            - Complete datastore with status data (default type).
+ \[bu] \fBconfig\fP          - Configuration datastore (without status data).
+ \[bu] \fBget\fP             - Result of the NETCONF <get> operation.
+ \[bu] \fBgetconfig\fP       - Result of the NETCONF <get-config> operation.
+ \[bu] \fBedit\fP            - Content of the NETCONF <edit-config> operation.
+ \[bu] \fBrpc\fP             - Content of the NETCONF <rpc> message, defined as YANG's rpc input statement.
+ \[bu] \fBrpcreply\fP        - Reply to the RPC. This is just a virtual \fITYPE\fP, for parsing replies, '\fBauto\fP' must be used since the data \fIFILE\fPs are expected in pairs.
+.br
+                     The first input data \fIFILE\fP is expected as '\fBrpc\fP' \fITYPE\fP, the second \fIFILE\fP is expected as reply to the previous RPC.
+ \[bu] \fBnotif\fP           - Notification instance (content of the <notification> element without <eventTime>.
+.TP
+.BR "\-O \fIFILE\fP\fR,\fP \-\^\-operational=\fIFILE\fP]
+Optional parameter for '\fBrpc\fP' and '\fBnotif\fP' \fITYPE\fPs, the \fIFILE\fP contains running configuration datastore and
+state data referenced from the RPC/Notification. The same data apply to all input data \fIFILE\fPs. Note that the file
+is validated as '\fBdata\fP' \fITYPE\fP. Special value '\fB!\fP' can be used as \fIFILE\fP argument to ignore the external references.
+.TP
+.BR "\-y \fIYANGLIB_PATH\fP"
+Specify path to a yang-library data file (XML or JSON) describing the initial context.
+If provided, yanglint loads the modules according to the content of the yang-library data tree.
+Otherwise, an empty content with only the internal libyang modules is used. This does
+not limit user to load another modules explicitly specified as command line parameters.
+.
+.SH FORMATS
+There are two types of formats to use.
+.TP
+.I Schemas
+In case of schemas, the content can be converted into the '\fByang\fP', '\fByin\fP'
+and '\fBtree\fP' formats. As input, only YANG and YIN files are
+accepted. Note, that the corresponding file extension is required.
+.TP
+.I Data\ \ \
+In case of YANG modeled data, the content can be converted between '\fBxml\fP'
+and '\fBjson\fP' formats. Remember that the corresponding file extension of the
+input file is required.
+.
+
+.SH EXAMPLES
+.IP \[bu] 2
+Open interactive environment:
+    yanglint
+.IP \[bu]
+Convert YANG model into YIN and print it to the stdout:
+    yanglint --format=yin ./ietf-system.yang
+.IP \[bu]
+Convert ietf-system configuration data from XML to JSON:
+    yanglint --format=json --type=config --output=data.json ./ietf-system.yang ./data.xml
+
+.SH SEE ALSO
+https://github.com/CESNET/libyang (libyang homepage and Git repository)
+.
+.SH AUTHORS
+Radek Krejci <rkrejci@cesnet.cz>, Michal Vasko <mvasko@cesnet.cz>
+.
+.SH COPYRIGHT
+Copyright \(co 2015-2017 CESNET, a.l.e.