daemonize.h

#ifndef WIN32
#include <errno.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#endif

void daemonize()
{
#ifndef WIN32
	pid_t pid, sid;

	/* already a daemon */
	if ( getppid() == 1 ) return;

	/* Fork off the parent process */
	pid = fork();
	if (pid < 0) {
		exit(EXIT_FAILURE);
	}
	/* If we got a good PID, then we can exit the parent process. */
	if (pid > 0) {
		exit(EXIT_SUCCESS);
	}

	/* At this point we are executing as the child process */

	/* Change the file mode mask */
	umask(0);

	/* Create a new SID for the child process */
	sid = setsid();
	if (sid < 0) {
		exit(EXIT_FAILURE);
	}

	/* Redirect standard files to /dev/null */
	freopen( "/dev/null", "r", stdin);
	freopen( "/dev/null", "w", stdout);
	freopen( "/dev/null", "w", stderr);
#endif 
}