108 lines
3 KiB
C++
108 lines
3 KiB
C++
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#include "stlexam.h"
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#pragma hdrstop
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/**************************************************************************
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*
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* mutex.cpp - Example program for mutex. See Class Reference Section
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*
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***************************************************************************
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*
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* (c) Copyright 1994, 1998 Rogue Wave Software, Inc.
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* ALL RIGHTS RESERVED
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*
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* The software and information contained herein are proprietary to, and
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* comprise valuable trade secrets of, Rogue Wave Software, Inc., which
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* intends to preserve as trade secrets such software and information.
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* This software is furnished pursuant to a written license agreement and
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* may be used, copied, transmitted, and stored only in accordance with
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* the terms of such license and with the inclusion of the above copyright
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* notice. This software and information or any other copies thereof may
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* not be provided or otherwise made available to any other person.
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*
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* Notwithstanding any other lease or license that may pertain to, or
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* accompany the delivery of, this computer software and information, the
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* rights of the Government regarding its use, reproduction and disclosure
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* are as set forth in Section 52.227-19 of the FARS Computer
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* Software-Restricted Rights clause.
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*
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* Use, duplication, or disclosure by the Government is subject to
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* restrictions as set forth in subparagraph (c)(1)(ii) of the Rights in
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* Technical Data and Computer Software clause at DFARS 252.227-7013.
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* Contractor/Manufacturer is Rogue Wave Software, Inc.,
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* P.O. Box 2328, Corvallis, Oregon 97339.
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*
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* This computer software and information is distributed with "restricted
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* rights." Use, duplication or disclosure is subject to restrictions as
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* set forth in NASA FAR SUP 18-52.227-79 (April 1985) "Commercial
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* Computer Software-Restricted Rights (April 1985)." If the Clause at
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* 18-52.227-74 "Rights in Data General" is specified in the contract,
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* then the "Alternate III" clause applies.
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*
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**************************************************************************/
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//
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// This is a code snippet illustrating how to use mutexes to
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// synchronize resources in a multi-threaded program.
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//
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#include <rw/stdmutex.h>
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#ifdef _RW_STD_IOSTREAM
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#include <iostream>
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#else
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#include <iostream.h>
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#endif
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#ifndef _RWSTD_NO_NAMESPACE
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using namespace std;
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#endif
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#ifdef _RWSTD_MULTI_THREAD
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//
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// An integer shared amongst multiple threads.
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//
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int I;
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//
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// A mutex used to synchronize updates to I.
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//
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_RWSTDMutex I_mutex;
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//
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// Increment I by one. Uses a _RWSTDMutex directly.
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//
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void increment_I ()
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{
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I_mutex.acquire(); // Lock the mutex.
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I++;
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I_mutex.release(); // Unlock the mutex.
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}
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//
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// Decrement I by one. Uses a _RWSTDGuard.
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//
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void decrement_I ()
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{
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_RWSTDGuard guard(I_mutex); // Acquire the lock on I_mutex.
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--I;
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//
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// The lock on I is released when destructor is called on guard.
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//
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}
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#endif
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int main()
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{
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#ifdef _RWSTD_MULTI_THREAD
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increment_I();
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decrement_I();
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cout << "Multi Threading enabled" << endl;
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#else
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cout << "Multi Threading not enabled" << endl;
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#endif
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return 0;
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}
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