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/*
* Copyright (C) 2011- The University of Notre Dame
* This software is distributed under the GNU General Public License.
* See the file COPYING for details.
*/
#include "daemon.h"
#include "debug.h"
#include "fd.h"
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
void daemonize (int cdroot, const char *pidfile)
{
/* Become session leader and lose controlling terminal */
pid_t pid = fork();
if (pid < 0) {
fatal("could not fork: %s", strerror(errno));
} else if (pid > 0) {
exit(EXIT_SUCCESS); /* exit parent */
}
pid_t group = setsid();
if (group == (pid_t) -1) {
fatal("could not create session: %s", strerror(errno));
}
/* Second fork ensures process cannot acquire controlling terminal */
pid = fork();
if (pid < 0) {
fatal("could not fork: %s", strerror(errno));
} else if (pid > 0) {
exit(EXIT_SUCCESS); /* exit parent */
}
if (pidfile && strlen(pidfile)) {
FILE *file = fopen(pidfile, "w");
if (file) {
fprintf(file, "%ld", (long)getpid());
fclose(file);
} else {
fatal("could not open `%s' for writing: %s", pidfile, strerror(errno));
}
}
if (cdroot){
int status = chdir("/");
if (status == -1) {
fatal("could not chdir to `/': %s", strerror(errno));
}
}
umask(0);
fd_nonstd_close();
FILE *file0 = freopen("/dev/null", "r", stdin);
if (file0 == NULL) {
fatal("could not reopen stdin: %s", strerror(errno));
}
FILE *file1 = freopen("/dev/null", "w", stdout);
if (file1 == NULL) {
fatal("could not reopen stdout: %s", strerror(errno));
}
FILE *file2 = freopen("/dev/null", "w", stderr);
if (file2 == NULL) {
fatal("could not reopen stderr: %s", strerror(errno));
}
debug_reopen();
}
/* vim: set noexpandtab tabstop=4: */
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