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
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
#ifndef foodaemonforkhfoo
#define foodaemonforkhfoo
/*
* This file is part of libdaemon.
*
* libdaemon is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* libdaemon is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with libdaemon; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
#include <sys/types.h>
/** \mainpage
*
* For a brief explanation of libdaemons's purpose, have a look on <a
* href="../../README.html">the README file</a>. Thank you!
*
*/
/** \example testd.c
* This is an example for the usage of libdaemon
*/
/** \file
*
* Contains an API for doing a daemonizing fork().
*
* You may daemonize by calling daemon_fork(), a function similar to
* the plain fork(). If you want to return a return value of the
* initialization procedure of the child from the parent, you may use
* the daemon_retval_xxx() functions.
*/
/** Does a daemonizing fork(). For the new daemon process STDIN,
* STDOUT, STDERR are connected to /dev/null, the process is a session
* leader, the current directory is changed to /, the umask is set to
* 777.
* @return zero on success in the child, the PID of the new
* daemon process in the parent, nonzero on failure
*/
pid_t daemon_fork(void);
/** Initializes the library for allowing the passing of a return value
* from the daemon initialization to the parent process. Call this
* before calling any of the other daemon_retval_xxx() functions in
* the parent, before forking.
* @return zero on success, nonzero on failure.
*/
int daemon_retval_init(void);
/** Frees the resources allocated by daemon_retval_init(). This should
* be called if neither daemon_retval_wait() nor daemon_retval_send()
* is used. If a fork took place, the function should be called in
* both the parent and the daemon. */
void daemon_retval_done(void);
/** Wait the specified amount of seconds for the response of the
* daemon process and return the integer passed to
* daemon_retval_send() in the daemon process. Should be called just
* once from the parent process only. A subsequent call to
* daemon_retval_done() in the parent is ignored.
* @param timeout The timeout in seconds
* @return The integer passed daemon_retval_send() in the daemon
* process, or negative on failure.
*/
int daemon_retval_wait(int timeout);
/** Send the specified integer to the parent process. Should be called
* just once from the daemon process only. A subsequent call to
* daemon_retval_done() in the daemon is ignored.
* @param s The integer to pass to daemon_retval_wait() in the parent process
* @return Zero on success, nonzero on failure.
*/
int daemon_retval_send(int s);
#endif
|