freebsd-dev/usr.bin/nohup/nohup.c
1999-08-28 01:08:13 +00:00

124 lines
3.6 KiB
C

/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1989, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)nohup.c 8.1 (Berkeley) 6/6/93";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
void dofile __P((void));
static void usage __P((void));
int
main(argc, argv)
int argc;
char *argv[];
{
if (argc < 2)
usage();
if (isatty(STDOUT_FILENO))
dofile();
if (isatty(STDERR_FILENO) && dup2(STDOUT_FILENO, STDERR_FILENO) == -1) {
/* may have just closed stderr */
(void)fprintf(stdin, "nohup: %s\n", strerror(errno));
exit(1);
}
(void)signal(SIGHUP, SIG_IGN);
(void)signal(SIGQUIT, SIG_IGN);
execvp(argv[1], &argv[1]);
err(1, "%s", argv[1]);
}
void
dofile()
{
int append;
int fd;
char *p, path[MAXPATHLEN];
#define FILENAME "nohup.out"
p = FILENAME;
append = !access(p, F_OK);
if ((fd = open(p, O_RDWR|O_CREAT, S_IRUSR | S_IWUSR)) >= 0)
goto dupit;
if ((p = getenv("HOME"))) {
(void)strcpy(path, p);
(void)strcat(path, "/");
(void)strcat(path, FILENAME);
append = !access(path, F_OK);
if ((fd = open(p = path,
O_RDWR|O_CREAT, S_IRUSR | S_IWUSR)) >= 0)
goto dupit;
}
errx(1, "can't open a nohup.out file");
dupit: (void)lseek(fd, (off_t)0, SEEK_END);
if (dup2(fd, STDOUT_FILENO) == -1)
err(1, NULL);
if (append)
(void)fprintf(stderr, "appending output to existing %s\n", p);
else
(void)fprintf(stderr, "sending output to %s\n", p);
}
void
usage()
{
(void)fprintf(stderr, "usage: nohup command\n");
exit(1);
}