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#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <errno.h>
#include <sys/param.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include "daemon.h"
int daemon_start(int ignsigcld)
{
/* Code to initialiaze a daemon process. Taken from _UNIX Network */
/* Programming_ pp.72-85, by W. Richard Stephens, Prentice */
/* Hall PTR, 1990 */
register int childpid, fd;
/* If started by init, don't bother */
if (getppid() == 1)
goto out;
/* Ignore the terminal stop signals */
signal(SIGTTOU, SIG_IGN);
signal(SIGTTIN, SIG_IGN);
signal(SIGTSTP, SIG_IGN);
/* Fork and let parent exit, insures we're not a process group leader */
if ((childpid = fork()) < 0) {
return 0;
} else if (childpid > 0) {
exit(0);
}
/* Disassociate from controlling terminal and process group. */
/* Ensure the process can't reacquire a new controlling terminal. */
if (setpgrp() == -1)
return 0;
if ((fd = open("/dev/tty", O_RDWR)) >= 0) {
/* loose controlling tty */
ioctl(fd, TIOCNOTTY, NULL);
close(fd);
}
out:
/* Move the current directory to root, to make sure we aren't on a */
/* mounted filesystem. */
chdir("/");
/* Clear any inherited file mode creation mask. */
umask(0);
if (ignsigcld)
signal(SIGCHLD, SIG_IGN);
/* That's it, we're a "daemon" process now */
return 1;
}
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