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 "h/done.h"
  11 #include "m_mktemp.h"
  12
  13
  14 void
  15 push(void)
  16 {
  17     pid_t pid;
  18
  19     pid = fork();
  20     switch (pid) {
  21         case -1:
  22             /* fork error */
  23             inform("unable to fork, so can't push...");
  24             break;
  25
  26         case 0:
  27             /* child, block a few signals and continue */
  28             SIGNAL (SIGHUP, SIG_IGN);
  29             SIGNAL (SIGINT, SIG_IGN);
  30             SIGNAL (SIGQUIT, SIG_IGN);
  31             SIGNAL (SIGTERM, SIG_IGN);
  32 #ifdef SIGTSTP
  33             SIGNAL (SIGTSTP, SIG_IGN);
  34             SIGNAL (SIGTTIN, SIG_IGN);
  35             SIGNAL (SIGTTOU, SIG_IGN);
  36 #endif
  37
  38             unregister_for_removal(0);
  39
  40             if (freopen ("/dev/null", "r", stdin) == NULL) {
  41                 advise ("stdin", "freopen");
  42             }
  43             if (freopen ("/dev/null", "w", stdout) == NULL) {
  44                 advise ("stdout", "freopen");
  45             }
  46             break;
  47
  48         default:
  49             /* parent, just exit */
  50             done (0);
  51     }
  52 }