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diff --git a/doc/html/qmutex.html b/doc/html/qmutex.html deleted file mode 100644 index 6727c60a4..000000000 --- a/doc/html/qmutex.html +++ /dev/null @@ -1,195 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> -<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/src/tools/qmutex_unix.cpp:333 --> -<html> -<head> -<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> -<title>TQMutex Class</title> -<style type="text/css"><!-- -fn { margin-left: 1cm; text-indent: -1cm; } -a:link { color: #004faf; text-decoration: none } -a:visited { color: #672967; text-decoration: none } -body { background: #ffffff; color: black; } ---></style> -</head> -<body> - -<table border="0" cellpadding="0" cellspacing="0" width="100%"> -<tr bgcolor="#E5E5E5"> -<td valign=center> - <a href="index.html"> -<font color="#004faf">Home</font></a> - | <a href="classes.html"> -<font color="#004faf">All Classes</font></a> - | <a href="mainclasses.html"> -<font color="#004faf">Main Classes</font></a> - | <a href="annotated.html"> -<font color="#004faf">Annotated</font></a> - | <a href="groups.html"> -<font color="#004faf">Grouped Classes</font></a> - | <a href="functions.html"> -<font color="#004faf">Functions</font></a> -</td> -<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>TQMutex Class Reference</h1> - -<p>The TQMutex class provides access serialization between threads. -<a href="#details">More...</a> -<p>All the functions in this class are <a href="threads.html#threadsafe">thread-safe</a> when TQt is built with thread support.</p> -<p><tt>#include <<a href="qmutex-h.html">qmutex.h</a>></tt> -<p><a href="qmutex-members.html">List of all member functions.</a> -<h2>Public Members</h2> -<ul> -<li class=fn><a href="#TQMutex"><b>TQMutex</b></a> ( bool recursive = FALSE )</li> -<li class=fn>virtual <a href="#~TQMutex"><b>~TQMutex</b></a> ()</li> -<li class=fn>void <a href="#lock"><b>lock</b></a> ()</li> -<li class=fn>void <a href="#unlock"><b>unlock</b></a> ()</li> -<li class=fn>bool <a href="#locked"><b>locked</b></a> ()</li> -<li class=fn>bool <a href="#tryLock"><b>tryLock</b></a> ()</li> -</ul> -<hr><a name="details"></a><h2>Detailed Description</h2> - - - -The TQMutex class provides access serialization between threads. -<p> - -<p> The purpose of a TQMutex is to protect an object, data structure or -section of code so that only one thread can access it at a time -(This is similar to the Java <tt>synchronized</tt> keyword). For -example, say there is a method which prints a message to the user -on two lines: -<p> <pre> - int number = 6; - - void method1() - { - number *= 5; - number /= 4; - } - - void method2() - { - number *= 3; - number /= 2; - } - </pre> - -<p> If these two methods are called in succession, the following happens: -<p> <pre> - // method1() - number *= 5; // number is now 30 - number /= 4; // number is now 7 - - // method2() - number *= 3; // nubmer is now 21 - number /= 2; // number is now 10 - </pre> - -<p> If these two methods are called simultaneously from two threads then the -following sequence could result: -<p> <pre> - // Thread 1 calls method1() - number *= 5; // number is now 30 - - // Thread 2 calls method2(). - // - // Most likely Thread 1 has been put to sleep by the operating - // system to allow Thread 2 to run. - number *= 3; // number is now 90 - number /= 2; // number is now 45 - - // Thread 1 finishes executing. - number /= 4; // number is now 11, instead of 10 - </pre> - -<p> If we add a mutex, we should get the result we want: -<p> <pre> - TQMutex mutex; - int number = 6; - - void method1() - { - mutex.<a href="#lock">lock</a>(); - number *= 5; - number /= 4; - mutex.<a href="#unlock">unlock</a>(); - } - - void method2() - { - mutex.<a href="#lock">lock</a>(); - number *= 3; - number /= 2; - mutex.<a href="#unlock">unlock</a>(); - } - </pre> - -<p> Then only one thread can modify <tt>number</tt> at any given time and -the result is correct. This is a trivial example, of course, but -applies to any other case where things need to happen in a -particular sequence. -<p> When you call <a href="#lock">lock</a>() in a thread, other threads that try to call -lock() in the same place will block until the thread that got the -lock calls <a href="#unlock">unlock</a>(). A non-blocking alternative to lock() is -<a href="#tryLock">tryLock</a>(). -<p>See also <a href="environment.html">Environment Classes</a> and <a href="thread.html">Threading</a>. - -<hr><h2>Member Function Documentation</h2> -<h3 class=fn><a name="TQMutex"></a>TQMutex::TQMutex ( bool recursive = FALSE ) -</h3> -Constructs a new mutex. The mutex is created in an unlocked state. -A recursive mutex is created if <em>recursive</em> is TRUE; a normal -mutex is created if <em>recursive</em> is FALSE (the default). With a -recursive mutex, a thread can lock the same mutex multiple times -and it will not be unlocked until a corresponding number of -<a href="#unlock">unlock</a>() calls have been made. - -<h3 class=fn><a name="~TQMutex"></a>TQMutex::~TQMutex ()<tt> [virtual]</tt> -</h3> -Destroys the mutex. -<p> <b>Warning:</b> If you destroy a mutex that still holds a lock the -resultant behavior is undefined. - -<h3 class=fn>void <a name="lock"></a>TQMutex::lock () -</h3> -Attempt to lock the mutex. If another thread has locked the mutex -then this call will <em>block</em> until that thread has unlocked it. -<p> <p>See also <a href="#unlock">unlock</a>() and <a href="#locked">locked</a>(). - -<h3 class=fn>bool <a name="locked"></a>TQMutex::locked () -</h3> -Returns TRUE if the mutex is locked by another thread; otherwise -returns FALSE. -<p> <b>Warning:</b> Due to differing implementations of recursive mutexes on -various platforms, calling this function from the same thread that -previously locked the mutex will return undefined results. -<p> <p>See also <a href="#lock">lock</a>() and <a href="#unlock">unlock</a>(). - -<h3 class=fn>bool <a name="tryLock"></a>TQMutex::tryLock () -</h3> -Attempt to lock the mutex. If the lock was obtained, this function -returns TRUE. If another thread has locked the mutex, this -function returns FALSE, instead of waiting for the mutex to become -available, i.e. it does not block. -<p> If the lock was obtained, the mutex must be unlocked with <a href="#unlock">unlock</a>() -before another thread can successfully lock it. -<p> <p>See also <a href="#lock">lock</a>(), <a href="#unlock">unlock</a>(), and <a href="#locked">locked</a>(). - -<h3 class=fn>void <a name="unlock"></a>TQMutex::unlock () -</h3> -Unlocks the mutex. Attempting to unlock a mutex in a different -thread to the one that locked it results in an error. Unlocking a -mutex that is not locked results in undefined behaviour (varies -between different Operating Systems' thread implementations). -<p> <p>See also <a href="#lock">lock</a>() and <a href="#locked">locked</a>(). - -<!-- eof --> -<hr><p> -This file is part of the <a href="index.html">TQt toolkit</a>. -Copyright © 1995-2007 -<a href="http://www.trolltech.com/">Trolltech</a>. 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