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diff --git a/doc/src/classes/qwaitcondition.qdoc b/doc/src/classes/qwaitcondition.qdoc deleted file mode 100644 index f19f51e..0000000 --- a/doc/src/classes/qwaitcondition.qdoc +++ /dev/null @@ -1,188 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). -** Contact: Nokia Corporation (qt-info@nokia.com) -** -** This file is part of the documentation of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** No Commercial Usage -** This file contains pre-release code and may not be distributed. -** You may use this file in accordance with the terms and conditions -** contained in the either Technology Preview License Agreement or the -** Beta Release License Agreement. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 2.1 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 2.1 requirements -** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. -** -** In addition, as a special exception, Nokia gives you certain -** additional rights. These rights are described in the Nokia Qt LGPL -** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this -** package. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 3.0 as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL included in the -** packaging of this file. Please review the following information to -** ensure the GNU General Public License version 3.0 requirements will be -** met: http://www.gnu.org/copyleft/gpl.html. -** -** If you are unsure which license is appropriate for your use, please -** contact the sales department at http://qt.nokia.com/contact. -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \class QWaitCondition - \brief The QWaitCondition class provides a condition variable for - synchronizing threads. - - \threadsafe - - \ingroup thread - \ingroup environment - - QWaitCondition allows a thread to tell other threads that some - sort of condition has been met. One or many threads can block - waiting for a QWaitCondition to set a condition with wakeOne() or - wakeAll(). Use wakeOne() to wake one randomly selected condition or - wakeAll() to wake them all. - - For example, let's suppose that we have three tasks that should - be performed whenever the user presses a key. Each task could be - split into a thread, each of which would have a - \l{QThread::run()}{run()} body like this: - - \snippet doc/src/snippets/code/src_corelib_thread_qwaitcondition_unix.cpp 0 - - Here, the \c keyPressed variable is a global variable of type - QWaitCondition. - - A fourth thread would read key presses and wake the other three - threads up every time it receives one, like this: - - \snippet doc/src/snippets/code/src_corelib_thread_qwaitcondition_unix.cpp 1 - - The order in which the three threads are woken up is undefined. - Also, if some of the threads are still in \c do_something() when - the key is pressed, they won't be woken up (since they're not - waiting on the condition variable) and so the task will not be - performed for that key press. This issue can be solved using a - counter and a QMutex to guard it. For example, here's the new - code for the worker threads: - - \snippet doc/src/snippets/code/src_corelib_thread_qwaitcondition_unix.cpp 2 - - Here's the code for the fourth thread: - - \snippet doc/src/snippets/code/src_corelib_thread_qwaitcondition_unix.cpp 3 - - The mutex is necessary because the results of two threads - attempting to change the value of the same variable - simultaneously are unpredictable. - - Wait conditions are a powerful thread synchronization primitive. - The \l{threads/waitconditions}{Wait Conditions} example shows how - to use QWaitCondition as an alternative to QSemaphore for - controlling access to a circular buffer shared by a producer - thread and a consumer thread. - - \sa QMutex, QSemaphore, QThread, {Wait Conditions Example} -*/ - -/*! - \fn QWaitCondition::QWaitCondition() - - Constructs a new wait condition object. -*/ - -/*! - \fn QWaitCondition::~QWaitCondition() - - Destroys the wait condition object. -*/ - -/*! - \fn void QWaitCondition::wakeOne() - - Wakes one thread waiting on the wait condition. The thread that - is woken up depends on the operating system's scheduling - policies, and cannot be controlled or predicted. - - If you want to wake up a specific thread, the solution is - typically to use different wait conditions and have different - threads wait on different conditions. - - \sa wakeAll() -*/ - -/*! - \fn void QWaitCondition::wakeAll() - - Wakes all threads waiting on the wait condition. The order in - which the threads are woken up depends on the operating system's - scheduling policies and cannot be controlled or predicted. - - \sa wakeOne() -*/ - -/*! - \fn bool QWaitCondition::wait(QMutex *mutex, unsigned long time) - - Releases the locked \a mutex and waits on the wait condition. The - \a mutex must be initially locked by the calling thread. If \a - mutex is not in a locked state, this function returns - immediately. If \a mutex is a recursive mutex, this function - returns immediately. The \a mutex will be unlocked, and the - calling thread will block until either of these conditions is met: - - \list - \o Another thread signals it using wakeOne() or wakeAll(). This - function will return true in this case. - \o \a time milliseconds has elapsed. If \a time is \c ULONG_MAX - (the default), then the wait will never timeout (the event - must be signalled). This function will return false if the - wait timed out. - \endlist - - The mutex will be returned to the same locked state. This - function is provided to allow the atomic transition from the - locked state to the wait state. - - \sa wakeOne(), wakeAll() -*/ - -/*! - \fn bool QWaitCondition::wait(QReadWriteLock *readWriteLock, unsigned long time) - \since 4.4 - - Releases the locked \a readWriteLock and waits on the wait - condition. The \a readWriteLock must be initially locked by the - calling thread. If \a readWriteLock is not in a locked state, this - function returns immediately. The \a readWriteLock must not be - locked recursively, otherwise this function will not release the - lock properly. The \a readWriteLock will be unlocked, and the - calling thread will block until either of these conditions is met: - - \list - \o Another thread signals it using wakeOne() or wakeAll(). This - function will return true in this case. - \o \a time milliseconds has elapsed. If \a time is \c ULONG_MAX - (the default), then the wait will never timeout (the event - must be signalled). This function will return false if the - wait timed out. - \endlist - - The \a readWriteLock will be returned to the same locked - state. This function is provided to allow the atomic transition - from the locked state to the wait state. - - \sa wakeOne(), wakeAll() -*/ |