    // ------------------------------- //
    // -------- Start of File -------- //
    // ------------------------------- //
    // ----------------------------------------------------------- //
    // C++ Source Code File Name: testprog.cpp
    // Compiler Used: MSVC, BCC32, GCC, HPUX aCC, SOLARIS CC
    // Produced By: DataReel Software Development Team
    // File Creation Date: 03/25/2000
    // Date Last Modified: 06/17/2016
    // Copyright (c) 2001-2025 DataReel Software Development
    // ----------------------------------------------------------- //
    // ------------- Program Description and Details ------------- //
    // ----------------------------------------------------------- //
    /*
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library 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
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
    USA

    Simple test program demonstrating the basic operation of the
    gxThread class using condition variables.
    */
    // ----------------------------------------------------------- //
    #include "gxdlcode.h"

    #if defined (__USE_ANSI_CPP__) // Use the ANSI Standard C++ library
    #include <iostream>
    using namespace std; // Use unqualified names for Standard C++ library
    #else // Use the old iostream library by default
    #include <iostream.h>
    #endif // __USE_ANSI_CPP__

    #include "gxthread.h"
    #include "gxcond.h"
    #include "gxmutex.h"

    #ifdef __MSVC_DEBUG__
    #include "leaktest.h"
    #endif

    // For safe condition variable usage, must use a Boolean predicate and
    // a mutex with the condition.
    int is_locked = 0;
    gxCondition cond;
    gxMutex mutex;

    class SimpleThread : public gxThread
    {
    private: // Base class interface
      void *ThreadEntryRoutine(gxThread_t *thread);
    };

    void *SimpleThread::ThreadEntryRoutine(gxThread_t *thread)
    // Thread's entry function
    {
      int num = *((int *)thread->GetThreadParm());

      // Serialize access to the shared resource.
      mutex.MutexLock();

      int num_try = 0;
      while(is_locked != 0) {
        if(++num_try < 255) {
          cout << "Thread " << num << " execution blocked..." << "\n" << flush;
          cond.ConditionWait(&mutex);
        }
        else {
          cout << "Thread " << num << " could not wait for condition"
    	   << "\n" << flush;
          mutex.MutexUnlock();
          return 0;
        }
      }

      // Tell other threads to wait until shared resource is available
      is_locked = 1;

      // ********** Enter Critical Section ******************* //
      cout << "Thread " << num << " accesing shared resource" << "\n" << flush;
      // ...
      // ...
      // ...
      cout << "Thread " << num << " releasing shared resource" << "\n" << flush;
      // ********** Leave Critical Section ******************* //

      // Tell other threads shared resource is available
      is_locked = 0;

      // Wake up the next thread waiting on this condition
      cond.ConditionSignal();
      mutex.MutexUnlock();

      return 0;
    }

    int main(int argc, char **argv)
    {
    #ifdef __MSVC_DEBUG__
      InitLeakTest();
    #endif

      const int NUM_THREADS = 5;
      SimpleThread t;
      gxThread_t *thread[NUM_THREADS];

      cout << "Create " << NUM_THREADS << " threads" << "\n" << flush;
      int i;
      for(i = 0; i < NUM_THREADS; i++) thread[i] = t.CreateThread((void *)&i);

      // Wait for the all the threads to finish before exiting
      cout << "Waiting for all threads before exiting" << "\n" << flush;
      for(i = 0; i < NUM_THREADS; ++i) t.JoinThread(thread[i]);

      // Release the memory allocated for each thread
      for(i = 0; i < NUM_THREADS; ++i) delete thread[i];

      cout << "Exiting program" << "\n" << flush;
      return 0;
    }
    // ----------------------------------------------------------- //
    // ------------------------------- //
    // --------- End of File --------- //
    // ------------------------------- //