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diff --git a/src/readlink.c b/src/readlink.c
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+/* readlink -- display value of a symbolic link.
+ Copyright (C) 2002-2022 Free Software Foundation, Inc.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Dmitry V. Levin */
+
+#include <config.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <sys/types.h>
+
+#include "system.h"
+#include "canonicalize.h"
+#include "error.h"
+#include "areadlink.h"
+
+/* The official name of this program (e.g., no 'g' prefix). */
+#define PROGRAM_NAME "readlink"
+
+#define AUTHORS proper_name ("Dmitry V. Levin")
+
+/* If true, do not output the trailing newline. */
+static bool no_newline;
+
+/* If true, report error messages. */
+static bool verbose;
+
+static struct option const longopts[] =
+{
+ {"canonicalize", no_argument, NULL, 'f'},
+ {"canonicalize-existing", no_argument, NULL, 'e'},
+ {"canonicalize-missing", no_argument, NULL, 'm'},
+ {"no-newline", no_argument, NULL, 'n'},
+ {"quiet", no_argument, NULL, 'q'},
+ {"silent", no_argument, NULL, 's'},
+ {"verbose", no_argument, NULL, 'v'},
+ {"zero", no_argument, NULL, 'z'},
+ {GETOPT_HELP_OPTION_DECL},
+ {GETOPT_VERSION_OPTION_DECL},
+ {NULL, 0, NULL, 0}
+};
+
+void
+usage (int status)
+{
+ if (status != EXIT_SUCCESS)
+ emit_try_help ();
+ else
+ {
+ printf (_("Usage: %s [OPTION]... FILE...\n"), program_name);
+ fputs (_("Print value of a symbolic link or canonical file name\n\n"),
+ stdout);
+ fputs (_("\
+ -f, --canonicalize canonicalize by following every symlink in\n\
+ every component of the given name recursively;\
+\n\
+ all but the last component must exist\n\
+ -e, --canonicalize-existing canonicalize by following every symlink in\n\
+ every component of the given name recursively,\
+\n\
+ all components must exist\n\
+"), stdout);
+ fputs (_("\
+ -m, --canonicalize-missing canonicalize by following every symlink in\n\
+ every component of the given name recursively,\
+\n\
+ without requirements on components existence\n\
+ -n, --no-newline do not output the trailing delimiter\n\
+ -q, --quiet\n\
+ -s, --silent suppress most error messages (on by default)\n\
+ -v, --verbose report error messages\n\
+ -z, --zero end each output line with NUL, not newline\n\
+"), stdout);
+ fputs (HELP_OPTION_DESCRIPTION, stdout);
+ fputs (VERSION_OPTION_DESCRIPTION, stdout);
+ emit_ancillary_info (PROGRAM_NAME);
+ }
+ exit (status);
+}
+
+int
+main (int argc, char **argv)
+{
+ /* If not -1, use this method to canonicalize. */
+ int can_mode = -1;
+ int status = EXIT_SUCCESS;
+ int optc;
+ bool use_nuls = false;
+
+ initialize_main (&argc, &argv);
+ set_program_name (argv[0]);
+ setlocale (LC_ALL, "");
+ bindtextdomain (PACKAGE, LOCALEDIR);
+ textdomain (PACKAGE);
+
+ atexit (close_stdout);
+
+ while ((optc = getopt_long (argc, argv, "efmnqsvz", longopts, NULL)) != -1)
+ {
+ switch (optc)
+ {
+ case 'e':
+ can_mode = CAN_EXISTING;
+ break;
+ case 'f':
+ can_mode = CAN_ALL_BUT_LAST;
+ break;
+ case 'm':
+ can_mode = CAN_MISSING;
+ break;
+ case 'n':
+ no_newline = true;
+ break;
+ case 'q':
+ case 's':
+ verbose = false;
+ break;
+ case 'v':
+ verbose = true;
+ break;
+ case 'z':
+ use_nuls = true;
+ break;
+ case_GETOPT_HELP_CHAR;
+ case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
+ default:
+ usage (EXIT_FAILURE);
+ }
+ }
+
+ if (optind >= argc)
+ {
+ error (0, 0, _("missing operand"));
+ usage (EXIT_FAILURE);
+ }
+
+ if (argc - optind > 1)
+ {
+ if (no_newline)
+ error (0, 0, _("ignoring --no-newline with multiple arguments"));
+ no_newline = false;
+ }
+
+ for (; optind < argc; ++optind)
+ {
+ char const *fname = argv[optind];
+ char *value = (can_mode != -1
+ ? canonicalize_filename_mode (fname, can_mode)
+ : areadlink_with_size (fname, 63));
+ if (value)
+ {
+ fputs (value, stdout);
+ if (! no_newline)
+ putchar (use_nuls ? '\0' : '\n');
+ free (value);
+ }
+ else
+ {
+ status = EXIT_FAILURE;
+ if (verbose)
+ error (0, errno, "%s", quotef (fname));
+ }
+ }
+
+ return status;
+}