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author | Lorry Tar Creator <lorry-tar-importer@lorry> | 2007-03-22 21:23:21 +0000 |
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committer | Lorry Tar Creator <lorry-tar-importer@lorry> | 2007-03-22 21:23:21 +0000 |
commit | cbf5993c43f49281173f185863577d86bfac6eae (patch) | |
tree | 90737c96cf15b97273a2bdc5950b3cf09f1d94ca /src/tty.c | |
download | coreutils-tarball-cbf5993c43f49281173f185863577d86bfac6eae.tar.gz |
coreutils-6.9coreutils-6.9
Diffstat (limited to 'src/tty.c')
-rw-r--r-- | src/tty.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/src/tty.c b/src/tty.c new file mode 100644 index 0000000..5228e7a --- /dev/null +++ b/src/tty.c @@ -0,0 +1,129 @@ +/* tty -- print the name of the terminal connected to standard input + Copyright (C) 1990-2005 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 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 "error.h" +#include "quote.h" + +/* Exit statuses. */ +enum + { + TTY_FAILURE = 2, + TTY_WRITE_ERROR = 3 + }; + +/* 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 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) + fprintf (stderr, _("Try `%s --help' for more information.\n"), + program_name); + 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); + printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT); + } + exit (status); +} + +int +main (int argc, char **argv) +{ + char *tty; + int optc; + + initialize_main (&argc, &argv); + 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])); + + tty = ttyname (STDIN_FILENO); + if (!silent) + { + if (tty) + puts (tty); + else + puts (_("not a tty")); + } + + exit (isatty (STDIN_FILENO) ? EXIT_SUCCESS : EXIT_FAIL); +} |