go-daemon/c-daemon/daemon/daemon.c
2023-07-27 12:22:51 +03:00

58 lines
No EOL
1.2 KiB
C

#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/fs.h>
#include <linux/limits.h>
#define NR_OPEN 1024
void logg(int num){
printf("You are in: %d\n",num);
}
int _daemon(int nochdir, int noclose){
pid_t pid, sid;
// pid_t defined in sys/types.h
// pid_t is a signed int data type
pid = fork(); // fork of the parent process
// fork() function defined in unistd.h
if (pid < 0){
exit(EXIT_FAILURE); // exit and EXIT_FAILURE defined in stdlib.h
}
else if (pid > 0){
exit(EXIT_SUCCESS);
}
sid = setsid();
if (sid < 0) {
exit(EXIT_FAILURE);
}
if ((chdir("/")) < 0) {
exit(EXIT_FAILURE);
}
if (!noclose) {
for (int i = 0; i < NR_OPEN; i++){
close(i);
// close(STDOUT_FILENO); => close(1);
// close(STDERR_FILENO); => close(2);
}
open("/dev/null", O_RDWR);
dup(0);
dup(0);
}
while (1) {
int status = system("/usr/lib/cdaemontmp/info");
// TODO SECURITY ISSUE
// LINK https://stackoverflow.com/questions/5237482/how-do-i-execute-an-external-program-within-c-code-in-linux-with-arguments#
sleep(1);
}
exit(EXIT_SUCCESS);
}