glib-threads.html

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</td>
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<td><p><span class="term"><em class="parameter"><code>priority</code></em>&#160;:</span></p></td>
<td>a priority for the thread.
</td>
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<td><p><span class="term"><em class="parameter"><code>error</code></em>&#160;:</span></p></td>
<td>return location for error.
</td>
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<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td>the new <a class="link" href="glib-Threads.html#GThread"><span class="type">GThread</span></a> on success.


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<div class="refsect2" lang="en">
<a name="id2884591"></a><h3>
<a name="g-thread-self"></a>g_thread_self ()</h3>
<a class="indexterm" name="id2884604"></a><pre class="programlisting"><a class="link" href="glib-Threads.html#GThread">GThread</a>*            g_thread_self                       (void);</pre>
<p>
This functions returns the <a class="link" href="glib-Threads.html#GThread"><span class="type">GThread</span></a> corresponding to the calling thread.
</p>
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<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td>the current thread.


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<hr>
<div class="refsect2" lang="en">
<a name="id2884650"></a><h3>
<a name="g-thread-join"></a>g_thread_join ()</h3>
<a class="indexterm" name="id2884662"></a><pre class="programlisting"><a class="link" href="glib-Basic-Types.html#gpointer">gpointer</a>            g_thread_join                       (<a class="link" href="glib-Threads.html#GThread">GThread</a> *thread);</pre>
<p>
Waits until <em class="parameter"><code>thread</code></em> finishes, i.e. the function <em class="parameter"><code>func</code></em>, as given
to <a class="link" href="glib-Threads.html#g-thread-create"><code class="function">g_thread_create()</code></a>, returns or <a class="link" href="glib-Threads.html#g-thread-exit"><code class="function">g_thread_exit()</code></a> is called by
<em class="parameter"><code>thread</code></em>. All resources of <em class="parameter"><code>thread</code></em> including the <a class="link" href="glib-Threads.html#GThread"><span class="type">GThread</span></a> struct are
released. <em class="parameter"><code>thread</code></em> must have been created with <em class="parameter"><code>joinable</code></em>=<a class="link" href="glib-Standard-Macros.html#TRUE:CAPS"><code class="literal">TRUE</code></a> in
<a class="link" href="glib-Threads.html#g-thread-create"><code class="function">g_thread_create()</code></a>. The value returned by <em class="parameter"><code>func</code></em> or given to
<a class="link" href="glib-Threads.html#g-thread-exit"><code class="function">g_thread_exit()</code></a> by <em class="parameter"><code>thread</code></em> is returned by this function.
</p>
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<td><p><span class="term"><em class="parameter"><code>thread</code></em>&#160;:</span></p></td>
<td>a <a class="link" href="glib-Threads.html#GThread"><span class="type">GThread</span></a> to be waited for.
</td>
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<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td>the return value of the thread.


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<hr>
<div class="refsect2" lang="en">
<a name="id2884839"></a><h3>
<a name="g-thread-set-priority"></a>g_thread_set_priority ()</h3>
<a class="indexterm" name="id2884852"></a><pre class="programlisting">void                g_thread_set_priority               (<a class="link" href="glib-Threads.html#GThread">GThread</a> *thread,
                                                         <a class="link" href="glib-Threads.html#GThreadPriority">GThreadPriority</a> priority);</pre>
<p>
Changes the priority of <em class="parameter"><code>thread</code></em> to <em class="parameter"><code>priority</code></em>.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
It is not guaranteed that threads with different priorities really
behave accordingly. On some systems (e.g. Linux) there are no thread
priorities. On other systems (e.g. Solaris) there doesn't seem to be
different scheduling for different priorities. All in all try to avoid
being dependent on priorities.
</p>
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<td><p><span class="term"><em class="parameter"><code>thread</code></em>&#160;:</span></p></td>
<td>a <a class="link" href="glib-Threads.html#GThread"><span class="type">GThread</span></a>.
</td>
</tr>
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<td><p><span class="term"><em class="parameter"><code>priority</code></em>&#160;:</span></p></td>
<td>a new priority for <em class="parameter"><code>thread</code></em>.


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<div class="refsect2" lang="en">
<a name="id2884958"></a><h3>
<a name="g-thread-yield"></a>g_thread_yield ()</h3>
<a class="indexterm" name="id2884971"></a><pre class="programlisting">void                g_thread_yield                      ();</pre>
<p>
Gives way to other threads waiting to be scheduled. 
</p>
<p>
This function is often used as a method to make busy wait less
evil. But in most cases you will encounter, there are better methods
to do that. So in general you shouldn't use this function.
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2885000"></a><h3>
<a name="g-thread-exit"></a>g_thread_exit ()</h3>
<a class="indexterm" name="id2885013"></a><pre class="programlisting">void                g_thread_exit                       (<a class="link" href="glib-Basic-Types.html#gpointer">gpointer</a> retval);</pre>
<p>
Exits the current thread. If another thread is waiting for that thread
using <a class="link" href="glib-Threads.html#g-thread-join"><code class="function">g_thread_join()</code></a> and the current thread is joinable, the waiting
thread will be woken up and get <em class="parameter"><code>retval</code></em> as the return value of
<a class="link" href="glib-Threads.html#g-thread-join"><code class="function">g_thread_join()</code></a>. If the current thread is not joinable, <em class="parameter"><code>retval</code></em> is
ignored. Calling
</p>
<p>
</p>
<div class="informalexample"><pre class="programlisting">
g_thread_exit (retval);
</pre></div>
<p>
</p>
<p>
is equivalent to calling 
</p>
<p>
</p>
<div class="informalexample"><pre class="programlisting">
return retval;
</pre></div>
<p>
</p>
<p>
in the function <em class="parameter"><code>func</code></em>, as given to <a class="link" href="glib-Threads.html#g-thread-create"><code class="function">g_thread_create()</code></a>.
</p>
<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Note</h3>
<p>
Never call <a class="link" href="glib-Threads.html#g-thread-exit"><code class="function">g_thread_exit()</code></a> from within a thread of a <a class="link" href="glib-Thread-Pools.html#GThreadPool"><span class="type">GThreadPool</span></a>, as
that will mess up the bookkeeping and lead to funny and unwanted results.
</p>
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<td><p><span class="term"><em class="parameter"><code>retval</code></em>&#160;:</span></p></td>
<td>the return value of this thread.


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<hr>
<div class="refsect2" lang="en">
<a name="id2885174"></a><h3>
<a name="g-thread-foreach"></a>g_thread_foreach ()</h3>
<a class="indexterm" name="id2885190"></a><pre class="programlisting">void                g_thread_foreach                    (<a class="link" href="glib-Doubly-Linked-Lists.html#GFunc">GFunc</a> thread_func,
                                                         <a class="link" href="glib-Basic-Types.html#gpointer">gpointer</a> user_data);</pre>
<p>
Call <em class="parameter"><code>thread_func</code></em> on all existing <a class="link" href="glib-Threads.html#GThread"><span class="type">GThread</span></a> structures. Note that
threads may decide to exit while <em class="parameter"><code>thread_func</code></em> is running, so
without intimate knowledge about the lifetime of foreign threads,
<em class="parameter"><code>thread_func</code></em> shouldn't access the GThread* pointer passed in as
first argument. However, <em class="parameter"><code>thread_func</code></em> will not be called for threads
which are known to have exited already.
</p>
<p>
Due to thread lifetime checks, this function has an execution complexity
which is quadratic in the number of existing threads.</p>
<p>

</p>
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<td><p><span class="term"><em class="parameter"><code>thread_func</code></em>&#160;:</span></p></td>
<td> function to call for all GThread structures
</td>
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<td><p><span class="term"><em class="parameter"><code>user_data</code></em>&#160;:</span></p></td>
<td>   second argument to <em class="parameter"><code>thread_func</code></em>
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<p class="since">Since  2.10
</p>
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<hr>
<div class="refsect2" lang="en">
<a name="id2885317"></a><h3>
<a name="GMutex"></a>GMutex</h3>
<a class="indexterm" name="id2885329"></a><pre class="programlisting">typedef struct _GMutex GMutex;</pre>
<p>
The <a class="link" href="glib-Threads.html#GMutex"><span class="type">GMutex</span></a> struct is an opaque data structure to represent a mutex
(mutual exclusion). It can be used to protect data against shared
access. Take for example the following function:

</p>
<div class="example">
<a name="id2885355"></a><p class="title"><b>Example&#160;2.&#160;A function which will not work in a threaded environment</b></p>
<div class="example-contents"><pre class="programlisting">
  int give_me_next_number ()