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diff --git a/src/tty.c b/src/tty.c
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+/* tty -- print the name of the terminal connected to standard input
+ Copyright (C) 1990-2022 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/>. */
+
+/* Displays "not a tty" if stdin is not a terminal.
+ Displays nothing if -s option is given.
+ Exit status 0 if stdin is a tty, 1 if not a tty, 2 if usage error,
+ 3 if write error.
+
+ Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
+
+#include <config.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <sys/types.h>
+
+#include "system.h"
+#include "error.h"
+#include "quote.h"
+
+/* Exit statuses. */
+enum
+ {
+ TTY_STDIN_NOTTY = 1,
+ TTY_FAILURE = 2,
+ TTY_WRITE_ERROR = 3
+ };
+
+/* The official name of this program (e.g., no 'g' prefix). */
+#define PROGRAM_NAME "tty"
+
+#define AUTHORS proper_name ("David MacKenzie")
+
+/* If true, return an exit status but produce no output. */
+static bool silent;
+
+static struct option const longopts[] =
+{
+ {"silent", no_argument, NULL, 's'},
+ {"quiet", no_argument, NULL, 's'},
+ {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]...\n"), program_name);
+ fputs (_("\
+Print the file name of the terminal connected to standard input.\n\
+\n\
+ -s, --silent, --quiet print nothing, only return an exit status\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)
+{
+ int optc;
+
+ initialize_main (&argc, &argv);
+ set_program_name (argv[0]);
+ setlocale (LC_ALL, "");
+ bindtextdomain (PACKAGE, LOCALEDIR);
+ textdomain (PACKAGE);
+
+ initialize_exit_failure (TTY_WRITE_ERROR);
+ atexit (close_stdout);
+
+ silent = false;
+
+ while ((optc = getopt_long (argc, argv, "s", longopts, NULL)) != -1)
+ {
+ switch (optc)
+ {
+ case 's':
+ silent = true;
+ break;
+
+ case_GETOPT_HELP_CHAR;
+
+ case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
+
+ default:
+ usage (TTY_FAILURE);
+ }
+ }
+
+ if (optind < argc)
+ {
+ error (0, 0, _("extra operand %s"), quote (argv[optind]));
+ usage (TTY_FAILURE);
+ }
+
+ errno = ENOENT;
+
+ if (silent)
+ return isatty (STDIN_FILENO) ? EXIT_SUCCESS : TTY_STDIN_NOTTY;
+
+ int status = EXIT_SUCCESS;
+ char const *tty = ttyname (STDIN_FILENO);
+
+ if (! tty)
+ {
+ tty = _("not a tty");
+ status = TTY_STDIN_NOTTY;
+ }
+
+ puts (tty);
+ return status;
+}