Files
infnoise/software/daemon.c
2019-03-21 22:14:15 +01:00

43 lines
945 B
C

// Functions used when running in the background
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <errno.h>
#include <unistd.h>
#include "infnoise.h"
// Write PID in a file
static bool writePid(int32_t pid, char *fileName) {
FILE *pidFile = fopen(fileName, "w");
if(pidFile == NULL) {
return false;
}
int ret = fprintf(pidFile, "%d\n", pid);
fclose(pidFile);
return (ret >= 0);
}
void startDaemon(struct opt_struct* opts) {
if(!opts->daemon) {
// No backgrounding, optionally write current PID
if(opts->pidFileName != NULL) {
writePid(getpid(), opts->pidFileName);
}
return;
}
int32_t pid = fork();
if(pid < 0) {
fputs("fork() failed\n", stderr);
exit(1);
}
if(pid > 0) {
// Parent
exit(opts->pidFileName != NULL
&& !writePid(pid, opts->pidFileName));
}
// Child
}