vncinsthandler.cpp
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// Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
//
// This file is part of the VNC system.
//
// The VNC system 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.
//
// 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, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
//
// If the source code for the VNC system is not available from the place
// whence you received this file, check http://www.uk.research.att.com/vnc or contact
// the authors on vnc@uk.research.att.com for information on obtaining it.
// vncInstHandler.cpp
// Implementation of the class used to ensure that only
// one instance is running
#include "stdhdrs.h"
#include "vncInstHandler.h"
// Name of the mutex
const char mutexname [] = "WinVNC_Win32_SC_Instance_Mutex";
// The class methods
vncInstHandler::vncInstHandler()
{
mutex=NULL;
}
vncInstHandler::~vncInstHandler()
{
if (mutex)
ReleaseMutex(mutex);
}
BOOL
vncInstHandler::Init()
{
// Create the named mutex
mutex = CreateMutex(NULL, FALSE, mutexname);
if (mutex == NULL)
return FALSE;
// Check that the mutex didn't already exist
if (GetLastError() == ERROR_ALREADY_EXISTS)
return FALSE;
return TRUE;
}