How to create a daemon process in linux using C

A good tutorial about this topic can be found here.

After creating it, compile it using gcc and run(eg:./a.out). U can see this daemon running as a child of init(see using pstree command). U can see the pid of this process using ps -e command.

Another one can be found here
Code:
#include "sys/types.h"
#include "sys/stat.h"
#include "stdio.h"
#include "stdlib.h"
#include "fcntl.h"
#include "errno.h"
#include "unistd.h"
#include "syslog.h"
#include "string.h"

int main(void) {

/* Our process ID and Session ID */
pid_t pid, sid;

/* 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);
}

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

/* Open any logs here */

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



/* Change the current working directory */
if ((chdir("/")) < 0) {
/* Log the failure */
exit(EXIT_FAILURE);
}

/* Close out the standard file descriptors */
close(STDIN_FILENO);
close(STDOUT_FILENO);
close(STDERR_FILENO);

/* Daemon-specific initialization goes here */

/* The Big Loop */
while (1) {
/* Do some task here ... */

sleep(30); /* wait 30 seconds */
}
exit(EXIT_SUCCESS);
}