diplodocus.org Git - nmh/blob - sbr/push.c

   1 /* push.c -- push a fork into the background
   2  *
   3  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   4  * COPYRIGHT file in the root directory of the nmh distribution for
   5  * complete copyright information.
   6  */
   7
   8 #include <h/mh.h>
   9 #include <h/signals.h>
  10 #include "m_mktemp.h"
  11
  12
  13 void
  14 push(void)
  15 {
  16     pid_t pid;
  17
  18     pid = fork();
  19     switch (pid) {
  20         case -1:
  21             /* fork error */
  22             inform("unable to fork, so can't push...");
  23             break;
  24
  25         case 0:
  26             /* child, block a few signals and continue */
  27             SIGNAL (SIGHUP, SIG_IGN);
  28             SIGNAL (SIGINT, SIG_IGN);
  29             SIGNAL (SIGQUIT, SIG_IGN);
  30             SIGNAL (SIGTERM, SIG_IGN);
  31 #ifdef SIGTSTP
  32             SIGNAL (SIGTSTP, SIG_IGN);
  33             SIGNAL (SIGTTIN, SIG_IGN);
  34             SIGNAL (SIGTTOU, SIG_IGN);
  35 #endif
  36
  37             unregister_for_removal(0);
  38
  39             if (freopen ("/dev/null", "r", stdin) == NULL) {
  40                 advise ("stdin", "freopen");
  41             }
  42             if (freopen ("/dev/null", "w", stdout) == NULL) {
  43                 advise ("stdout", "freopen");
  44             }
  45             break;
  46
  47         default:
  48             /* parent, just exit */
  49             done (0);
  50     }
  51 }