gdaemon_unix.cpp

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//
// Copyright (C) 2017 Graeme Walker
// 
// This program 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 3 of the License, or
// (at your option) any later version.
// 
// This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
// ===
//
// gdaemon_unix.cpp
//

#include "gdef.h"
#include "gdaemon.h"
#include "gprocess.h"
#include "gnewprocess.h"

void G::Daemon::detach( PidFile & pid_file )
{
    pid_file.check() ; // absolute path
    detach() ;
}

void G::Daemon::detach()
{
    // see Stevens, ISBN 0-201-563137-7, ch 13.

    if( !NewProcess::fork().first )
        ::_exit( 0 ) ; // exit from parent

    setsid() ;
    bool rc = Process::cd( "/" , Process::NoThrow() ) ; G_IGNORE_VARIABLE(rc) ;

    if( !NewProcess::fork().first )
        ::_exit( 0 ) ; // exit from parent
}

void G::Daemon::setsid()
{
    pid_t rc = ::setsid() ; G_IGNORE_VARIABLE(rc) ;
}

/// \file gdaemon_unix.cpp