macro and text revision (-mdoc version 3)

[unix-history] / usr / src / lib / libc / stdlib / system.c

/*
* Copyright (c) 1988 The Regents of the University of California.
* All rights reserved.
*
* %sccs.include.redist.c%
*/

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)system.c    5.10 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */

#include <sys/types.h>
#include <sys/signal.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <stddef.h>
#include <unistd.h>
#include <paths.h>

system(command)
       const char *command;
{
       union wait pstat;
       pid_t pid;
       int omask;
       sig_t intsave, quitsave;

       if (!command)           /* just checking... */
               return(1);

       omask = sigblock(sigmask(SIGCHLD));
       switch(pid = vfork()) {
       case -1:                        /* error */
               (void)sigsetmask(omask);
               pstat.w_status = 0;
               pstat.w_retcode = 127;
               return(pstat.w_status);
       case 0:                         /* child */
               (void)sigsetmask(omask);
               execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL);
               _exit(127);
       }
       intsave = signal(SIGINT, SIG_IGN);
       quitsave = signal(SIGQUIT, SIG_IGN);
       pid = waitpid(pid, (int *)&pstat, 0);
       (void)sigsetmask(omask);
       (void)signal(SIGINT, intsave);
       (void)signal(SIGQUIT, quitsave);
       return(pid == -1 ? -1 : pstat.w_status);
}