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/* tty -- print the path of the terminal connected to standard input
Copyright (C) 1990-2000 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 2, 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, write to the Free Software Foundation,
Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* 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, 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 "closeout.h"
#include "error.h"
/* The official name of this program (e.g., no `g' prefix). */
#define PROGRAM_NAME "tty"
#define AUTHORS "David MacKenzie"
/* The name under which this program was run. */
char *program_name;
/* If nonzero, return an exit status but produce no output. */
static int 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 != 0)
fprintf (stderr, _("Try `%s --help' for more information.\n"),
program_name);
else
{
printf (_("Usage: %s [OPTION]...\n"), program_name);
printf (_("\
Print the file name of the terminal connected to standard input.\n\
\n\
-s, --silent, --quiet print nothing, only return an exit status\n\
--help display this help and exit\n\
--version output version information and exit\n\
"));
puts (_("\nReport bugs to <bug-sh-utils@gnu.org>."));
}
exit (status);
}
int
main (int argc, char **argv)
{
char *tty;
int optc;
program_name = argv[0];
setlocale (LC_ALL, "");
bindtextdomain (PACKAGE, LOCALEDIR);
textdomain (PACKAGE);
close_stdout_set_status (3);
atexit (close_stdout);
silent = 0;
while ((optc = getopt_long (argc, argv, "s", longopts, NULL)) != -1)
{
switch (optc)
{
case 0:
break;
case 's':
silent = 1;
break;
case_GETOPT_HELP_CHAR;
case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
default:
usage (2);
}
}
if (optind != argc)
error (0, 0, _("ignoring all arguments"));
tty = ttyname (0);
if (!silent)
{
if (tty)
puts (tty);
else
puts (_("not a tty"));
}
exit (isatty (0) ? 0 : 1);
}
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