chiark / gitweb /
Commit as 2.1.0.
[mLib] / daemonize.c
CommitLineData
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1/* -*-c-*-
2 *
3 * $Id$
4 *
5 * Become a daemon, detaching from terminals
6 *
7 * (c) 2007 Straylight/Edgeware
8 */
9
d4efbcd9 10/*----- Licensing notice --------------------------------------------------*
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11 *
12 * This file is part of the mLib utilities library.
13 *
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
d4efbcd9 18 *
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19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
d4efbcd9 23 *
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24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
27 * MA 02111-1307, USA.
28 */
29
30/*----- Header files ------------------------------------------------------*/
31
32#include <sys/types.h>
33#include <unistd.h>
34#include <fcntl.h>
35#include <sys/ioctl.h>
36
37#include "daemonize.h"
38
39/*----- Main code ---------------------------------------------------------*/
40
41/* --- @detachtty@ --- *
42 *
43 * Arguments: ---
44 *
45 * Returns: ---
46 *
47 * Use: Detaches from the current terminal and ensures it can never
48 * acquire a new one. Calls @fork@.
49 */
50
51void detachtty(void)
52{
53#ifdef TIOCNOTTY
54 {
55 int fd;
56 if ((fd = open("/dev/tty", O_RDONLY)) >= 0) {
57 ioctl(fd, TIOCNOTTY);
58 close(fd);
59 }
60 }
61#endif
62 setsid();
63 if (fork() > 0)
64 _exit(0);
65}
66
67/* --- @daemonize@ --- *
68 *
69 * Arguments: ---
70 *
71 * Returns: Zero if OK, nonzero on failure.
72 *
73 * Use: Becomes a daemon.
74 */
75
76int daemonize(void)
77{
78 pid_t kid;
79
80 if ((kid = fork()) < 0)
81 return (-1);
82 if (kid)
83 _exit(0);
84 detachtty();
85 return (0);
86}
87
88/*----- That's all, folks -------------------------------------------------*/