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gdaemon.h
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1//
2// Copyright (C) 2001-2021 Graeme Walker <graeme_walker@users.sourceforge.net>
3//
4// This program is free software: you can redistribute it and/or modify
5// it under the terms of the GNU General Public License as published by
6// the Free Software Foundation, either version 3 of the License, or
7// (at your option) any later version.
8//
9// This program is distributed in the hope that it will be useful,
10// but WITHOUT ANY WARRANTY; without even the implied warranty of
11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12// GNU General Public License for more details.
13//
14// You should have received a copy of the GNU General Public License
15// along with this program. If not, see <http://www.gnu.org/licenses/>.
16// ===
17///
18/// \file gdaemon.h
19///
20
21#ifndef G_DAEMON_H
22#define G_DAEMON_H
23
24#include "gdef.h"
25#include "gexception.h"
26#include "gpidfile.h"
27#include "gpath.h"
28#include <sys/types.h>
29#include <string>
30
31 namespace G
32{
33 class Daemon ;
34}
35
36//| \class G::Daemon
37/// A static interface for daemonising the calling process. Daemonisation
38/// includes fork()ing, detaching from the controlling terminal, setting
39/// the process umask, etc. The windows implementation does nothing.
40/// \see G::Process
41///
42 class G::Daemon
43{
44 public:
45 static void detach() ;
46 ///< Detaches from the parent environment. This typically
47 ///< involves fork()ing, std::_Exit()ing the parent, and calling
48 ///< setsid() in the child.
49
50 static void detach( PidFile & pid_file ) ;
51 ///< An overload which allows for a delayed write of the
52 ///< new process-id to a file.
53 ///<
54 ///< A delayed write is useful for network daemons that open
55 ///< a listening port. A second instance of the process will
56 ///< fail on startup, and should not overwrite the pid file
57 ///< of the running server. In this situation PidFile::commit()
58 ///< should be called just before entering the event loop.
59 ///<
60 ///< Throws PidFile::Error on error.
61
62 public:
63 Daemon() = delete ;
64
65 private:
66 static void setsid() ;
67} ;
68
69#endif
G::Daemon
A static interface for daemonising the calling process.
Definition: gdaemon.h:43
G::Daemon::detach
static void detach()
Detaches from the parent environment.
Definition: gdaemon_unix.cpp:32
G::PidFile
A class for creating pid files.
Definition: gpidfile.h:57
gexception.h
gpath.h
gpidfile.h
G
Low-level classes.
Definition: galign.h:28