blob: dcc566947b78fdcef4547828f5375ecb93a84233 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <errno.h>
#include <sys/param.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <netax25/daemon.h>
int daemon_start(int ignsigcld)
{
/* Code to initialize a daemon process. Taken from _UNIX Network */
/* Programming_ pp.72-85, by W. Richard Stephens, Prentice */
/* Hall PTR, 1990 */
int childpid;
/* If started by init, don't bother */
if (getppid() == 1)
goto out;
/* Ignore the terminal stop signals */
signal(SIGTTOU, SIG_IGN);
signal(SIGTTIN, SIG_IGN);
signal(SIGTSTP, SIG_IGN);
/* Fork and let parent exit, insures we're not a process group leader */
if ((childpid = fork()) < 0) {
return 0;
} else if (childpid > 0) {
exit(0);
}
/*
* Disassociate from controlling terminal and process group and
* ensure the process can't reacquire a new controlling terminal.
* We're freshly forked, so setsid can't fail.
*/
(void) setsid();
out:
/* Move the current directory to root, to make sure we aren't on a */
/* mounted filesystem. */
if (chdir("/") < 0)
return 0;
/* Clear any inherited file mode creation mask. */
umask(0);
if (ignsigcld)
signal(SIGCHLD, SIG_IGN);
/* That's it, we're a "daemon" process now */
return 1;
}
|