utils/src/tty.c

71 lines
1.4 KiB
C

/* $Id$ */
/* Copyright (c) 2009 Pierre Pronchery <khorben@defora.org> */
/* This file is part of DeforaOS Unix utils */
/* 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, version 3 of the License.
*
* 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 <http://www.gnu.org/licenses/>. */
#include <unistd.h>
#include <stdio.h>
/* tty */
static int _tty_error(char const * message, int ret);
static int _tty(void)
{
char * tty;
if(isatty(0) == 1)
{
if((tty = ttyname(0)) == NULL)
return _tty_error("ttyname", 2);
puts(tty);
return 0;
}
puts("not a tty");
return 1;
}
static int _tty_error(char const * message, int ret)
{
fputs("tty: ", stderr);
perror(message);
return ret;
}
/* usage */
static int _usage(void)
{
fputs("Usage: tty\n", stderr);
return 1;
}
/* main */
int main(int argc, char * argv[])
{
int o;
while((o = getopt(argc, argv, "")) != -1)
switch(o)
{
default:
return _usage();
}
if(optind != argc)
return _usage();
return _tty();
}