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RedHat 9 (Linux i386) - man page for qthread (redhat section 3qt)

QThread(3qt)									     QThread(3qt)

NAME
       QThread - Platform-independent threads

SYNOPSIS
       All the functions in this class are thread-safe when Qt is built with thread support.</p>

       #include <qthread.h>

       Inherits Qt.

   Public Members
       QThread ()
       QThread ( unsigned int stackSize )
       virtual ~QThread ()
       bool wait ( unsigned long time = ULONG_MAX )
       void start ()
       void terminate ()
       bool finished () const
       bool running () const

   Static Public Members
       Qt::HANDLE currentThread ()
       void postEvent ( QObject * receiver, QEvent * event )  (obsolete)
       void exit ()

   Protected Members
       virtual void run () = 0

   Static Protected Members
       void sleep ( unsigned long secs )
       void msleep ( unsigned long msecs )
       void usleep ( unsigned long usecs )

DESCRIPTION
       The QThread class provides platform-independent threads.

       A QThread represents a separate thread of control within the program; it shares data with
       all the other threads within the process but executes independently in the way that a
       separate program does on a multitasking operating system. Instead of starting in main(),
       QThreads begin executing in run(). You inherit run() to include your code. For example:

	   class MyThread : public QThread {
	   public:
	       virtual void run();
	   };
	   void MyThread::run()
	   {
	       for( int count = 0; count < 20; count++ ) {
		   sleep( 1 );
		   qDebug( "Ping!" );
	       }
	   }
	   int main()
	   {
	       MyThread a;
	       MyThread b;
	       a.start();
	       b.start();
	       a.wait();
	       b.wait();
	   }

       This will start two threads, each of which writes Ping! 20 times to the screen and exits.
       The wait() calls at the end of main() are necessary because exiting main() ends the
       program, unceremoniously killing all other threads. Each MyThread stops executing when it
       reaches the end of MyThread::run(), just as an application does when it leaves main().

       See also Thread Support in Qt, Environment Classes, and Threading.

MEMBER FUNCTION DOCUMENTATION
QThread::QThread ()
       Constructs a new thread. The thread does not begin executing until start() is called.

QThread::QThread ( unsigned int stackSize )
       Constructs a new thread. The thread does not begin executing until start() is called.

       If stackSize is greater than zero, the maximum stack size is set to stackSize bytes,
       otherwise the maximum stack size is automatically determined by the operating system.

       Warning: Most operating systems place minimum and maximum limits on thread stack sizes.
       The thread will fail to start if the stack size is outside these limits.

QThread::~QThread () [virtual]
       QThread destructor.

       Note that deleting a QThread object will not stop the execution of the thread it
       represents. Deleting a running QThread (i.e. finished() returns FALSE) will probably
       result in a program crash. You can wait() on a thread to make sure that it has finished.

Qt::HANDLE QThread::currentThread () [static]
       This returns the thread handle of the currently executing thread.

       Warning: The handle returned by this function is used for internal purposes and should not
       be used in any application code. On Windows, the returned value is a pseudo handle for the
       current thread, and it cannot be used for numerical comparison.

void QThread::exit () [static]
       Ends the execution of the calling thread and wakes up any threads waiting for its
       termination.

bool QThread::finished () const
       Returns TRUE is the thread is finished; otherwise returns FALSE.

void QThread::msleep ( unsigned long msecs ) [static protected]
       System independent sleep. This causes the current thread to sleep for msecs milliseconds

void QThread::postEvent ( QObject * receiver, QEvent * event ) [static]
       This function is obsolete. It is provided to keep old source working. We strongly advise
       against using it in new code.

       Use QApplication::postEvent() instead.

void QThread::run () [pure virtual protected]
       This method is pure virtual, and must be implemented in derived classes in order to do
       useful work. Returning from this method will end the execution of the thread.

       See also wait().

bool QThread::running () const
       Returns TRUE if the thread is running; otherwise returns FALSE.

void QThread::sleep ( unsigned long secs ) [static protected]
       System independent sleep. This causes the current thread to sleep for secs seconds.

void QThread::start ()
       This begins the execution of the thread by calling run(), which should be reimplemented in
       a QThread subclass to contain your code. If you try to start a thread that is already
       running, this call will wait until the thread has finished, and then restart the thread.

void QThread::terminate ()
       This function terminates the execution of the thread. The thread may or may not be
       terminated immediately, depending on the operating systems scheduling policies. Use
       QThread::wait() after terminate() for synchronous termination.

       When the thread is terminated, all threads waiting for the the thread to finish will be
       woken up.

       Warning: This function is dangerous, and its use is discouraged. The thread can be
       terminate at any point in its code path. Threads can be terminated while modifying data.
       There is no chance for the thread to cleanup after itself, unlock any held mutexes, etc.
       In short, use this function only if absolutely necessary.

void QThread::usleep ( unsigned long usecs ) [static protected]
       System independent sleep. This causes the current thread to sleep for usecs microseconds

bool QThread::wait ( unsigned long time = ULONG_MAX )
       This provides similar functionality to POSIX pthread_join. A thread calling this will
       block until either of these conditions is met:

       The thread associated with this QThread object has finished execution (i.e. when it
       returns from run()). This function will return TRUE if the thread has finished. It also
       returns TRUE if the thread has not been started yet.

	time milliseconds has elapsed. If time is ULONG_MAX (the
	      default), then the wait will never timeout (the thread must return from run()).
	      This function will return FALSE if the wait timed out.

SEE ALSO
       http://doc.trolltech.com/qthread.html http://www.trolltech.com/faq/tech.html

COPYRIGHT
       Copyright 1992-2001 Trolltech AS, http://www.trolltech.com.  See the license file included
       in the distribution for a complete license statement.

AUTHOR
       Generated automatically from the source code.

BUGS
       If you find a bug in Qt, please report it as described in
       http://doc.trolltech.com/bughowto.html.	Good bug reports help us to help you. Thank you.

       The definitive Qt documentation is provided in HTML format; it is located at
       $QTDIR/doc/html and can be read using Qt Assistant or with a web browser. This man page is
       provided as a convenience for those users who prefer man pages, although this format is
       not officially supported by Trolltech.

       If you find errors in this manual page, please report them to qt-bugs@trolltech.com.
       Please include the name of the manual page (qthread.3qt) and the Qt version (3.1.1).

Trolltech AS				 9 December 2002			     QThread(3qt)


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