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/*
* push.c -- push a fork into the background
*
* This code is Copyright (c) 2002, by the authors of nmh. See the
* COPYRIGHT file in the root directory of the nmh distribution for
* complete copyright information.
*/
#include <h/mh.h>
#include <h/signals.h>
void
push(void)
{
pid_t pid;
int i;
for (i = 0; (pid = fork()) == -1 && i < 5; i++)
sleep (5);
switch (pid) {
case -1:
/* fork error */
advise (NULL, "unable to fork, so can't push...");
break;
case 0:
/* child, block a few signals and continue */
SIGNAL (SIGHUP, SIG_IGN);
SIGNAL (SIGINT, SIG_IGN);
SIGNAL (SIGQUIT, SIG_IGN);
SIGNAL (SIGTERM, SIG_IGN);
#ifdef SIGTSTP
SIGNAL (SIGTSTP, SIG_IGN);
SIGNAL (SIGTTIN, SIG_IGN);
SIGNAL (SIGTTOU, SIG_IGN);
#endif
unregister_for_removal(0);
freopen ("/dev/null", "r", stdin);
freopen ("/dev/null", "w", stdout);
break;
default:
/* parent, just exit */
done (0);
}
}
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