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/*
* Copyright (c) 1988, 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)system.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include <stdlib.h>
#include <stddef.h>
#include <unistd.h>
#include <paths.h>
#include <errno.h>
int system(command)
const char *command;
{
pid_t pid;
int pstat;
struct sigaction ign, intact, quitact;
sigset_t newsigblock, oldsigblock;
if (!command) /* just checking... */
return(1);
/*
* Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save
* existing signal dispositions.
*/
ign.sa_handler = SIG_IGN;
(void)sigemptyset(&ign.sa_mask);
ign.sa_flags = 0;
(void)sigaction(SIGINT, &ign, &intact);
(void)sigaction(SIGQUIT, &ign, &quitact);
(void)sigemptyset(&newsigblock);
(void)sigaddset(&newsigblock, SIGCHLD);
(void)sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock);
switch(pid = fork()) {
case -1: /* error */
break;
case 0: /* child */
/*
* Restore original signal dispositions and exec the command.
*/
(void)sigaction(SIGINT, &intact, NULL);
(void)sigaction(SIGQUIT, &quitact, NULL);
(void)sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL);
_exit(127);
default: /* parent */
do {
pid = waitpid(pid, &pstat, 0);
} while (pid == -1 && errno == EINTR);
break;
}
(void)sigaction(SIGINT, &intact, NULL);
(void)sigaction(SIGQUIT, &quitact, NULL);
(void)sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
return(pid == -1 ? -1 : pstat);
}
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