2.11BSD#431 - /usr/src/lib/libc/gen/system.c

   1: /*
   2:  * Copyright (c) 1988 The Regents of the University of California.
   3:  * All rights reserved.
   4:  *
   5:  * Redistribution and use in source and binary forms, with or without
   6:  * modification, are permitted provided that the following conditions
   7:  * are met:
   8:  * 1. Redistributions of source code must retain the above copyright
   9:  *    notice, this list of conditions and the following disclaimer.
  10:  * 2. Redistributions in binary form must reproduce the above copyright
  11:  *    notice, this list of conditions and the following disclaimer in the
  12:  *    documentation and/or other materials provided with the distribution.
  13:  * 3. All advertising materials mentioning features or use of this software
  14:  *    must display the following acknowledgement:
  15:  *	This product includes software developed by the University of
  16:  *	California, Berkeley and its contributors.
  17:  * 4. Neither the name of the University nor the names of its contributors
  18:  *    may be used to endorse or promote products derived from this software
  19:  *    without specific prior written permission.
  20:  *
  21:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31:  * SUCH DAMAGE.
  32:  */
  33: 
  34: #if defined(LIBC_SCCS) && !defined(lint)
  35: static char sccsid[] = "@(#)system.c	5.10.1 (2.11BSD) 1999/10/24";
  36: #endif /* LIBC_SCCS and not lint */
  37: 
  38: #include <stdio.h>
  39: #include <sys/types.h>
  40: #include <sys/signal.h>
  41: #include <sys/wait.h>
  42: 
  43: system(command)
  44:     char *command;
  45: {
  46:     union wait pstat;
  47:     register int pid;
  48:     sigset_t omask, nmask;
  49:     int (*intsave)(), (*quitsave)();
  50: 
  51:     if (!command)       /* just checking... */
  52:         return(1);
  53: 
  54:     sigemptyset(&nmask);
  55:     sigaddset(&nmask, SIGCHLD);
  56:     (void)sigprocmask(SIG_BLOCK, &nmask, &omask);
  57:     switch(pid = vfork()) {
  58:     case -1:            /* error */
  59:         (void)sigprocmask(SIG_SETMASK, &omask, NULL);
  60:         pstat.w_status = 0;
  61:         pstat.w_retcode = 127;
  62:         return(pstat.w_status);
  63:     case 0:             /* child */
  64:         (void)sigprocmask(SIG_SETMASK, &omask, NULL);
  65:         execl("/bin/sh", "sh", "-c", command, (char *)NULL);
  66:         _exit(127);
  67:     }
  68:     intsave = signal(SIGINT, SIG_IGN);
  69:     quitsave = signal(SIGQUIT, SIG_IGN);
  70:     pid = waitpid(pid, (int *)&pstat, 0);
  71:     (void)sigprocmask(SIG_SETMASK, &omask, NULL);
  72:     (void)signal(SIGINT, intsave);
  73:     (void)signal(SIGQUIT, quitsave);
  74:     return(pid == -1 ? -1 : pstat.w_status);
  75: }

Defined functions

Defined variables