/* * 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. */ #include <sys/types.h>#include <sys/wait.h>#include <signal.h>#include <stdlib.h>#include <stddef.h>#include <unistd.h>#include <errno.h> intsystem(command)	const char *command;{	pid_t pid, savedpid;	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("/bin/sh", "sh", "-c", command, (char *)NULL);		_exit(127);	default:			/* parent */		savedpid = pid;		do {			pid = waitpid(savedpid, &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);}