gdk-threads.html

最新gtk中文资料集

      G_UNLOCK (yes_or_no);

      if (say_something)
	{
	  /* get GTK thread lock */
	  gdk_threads_enter ();

	  /* set label text */
	  if(data->what == YES_IT_IS)
	    gtk_label_set_text (GTK_LABEL (data->label), "O yes, it is!");
	  else
	    gtk_label_set_text (GTK_LABEL (data->label), "O no, it isn't!");

	  /* release GTK thread lock */
	  gdk_threads_leave ();
	}
    }

  return NULL;
}

int main (int argc, char *argv[])
{
  GtkWidget *window;
  GtkWidget *label;
  yes_or_no_args yes_args, no_args;
  pthread_t no_tid, yes_tid;

  /* init threads */
  g_thread_init (NULL);
  gdk_threads_init ();
  gdk_threads_enter ();

  /* init gtk */
  gtk_init(&argc, &argv);

  /* init random number generator */
  srand ((unsigned int) time (NULL));

  /* create a window */
  window = gtk_window_new (GTK_WINDOW_TOPLEVEL);

  gtk_signal_connect (GTK_OBJECT (window), "destroy",
		      GTK_SIGNAL_FUNC (destroy), NULL);

  gtk_container_set_border_width (GTK_CONTAINER (window), 10);

  /* create a label */
  label = gtk_label_new ("And now for something completely different ...");
  gtk_container_add (GTK_CONTAINER (window), label);
  
  /* show everything */
  gtk_widget_show (label);
  gtk_widget_show (window);

  /* create the threads */
  yes_args.label = label;
  yes_args.what = YES_IT_IS;
  pthread_create (&yes_tid, NULL, argument_thread, &yes_args);

  no_args.label = label;
  no_args.what = NO_IT_IS_NOT;
  pthread_create (&no_tid, NULL, argument_thread, &no_args);

  /* enter the GTK main loop */
  gtk_main ();
  gdk_threads_leave ();

  return 0;
}
</pre></div>
</div>
<div class="refsect1" lang="en">
<a name="id3281287"></a><h2>Details</h2>
<div class="refsect2" lang="en">
<a name="id3281297"></a><h3>
<a name="GDK-THREADS-ENTER:CAPS"></a>GDK_THREADS_ENTER()</h3>
<a class="indexterm" name="id3281311"></a><pre class="programlisting">#define             GDK_THREADS_ENTER()</pre>
<p>
This macro marks the beginning of a critical section in which GDK and
GTK+ functions can be called safely and without causing race
conditions.  Only one thread at a time can be in such a critial
section. The macro expands to a no-op if <a
href="/usr/share/gtk-doc/html/glib/glib-Threads.html#G-THREADS-ENABLED:CAPS"
><span class="type">G_THREADS_ENABLED</span></a> has not
been defined. Typically <a class="link" href="gdk-Threads.html#gdk-threads-enter"><code class="function">gdk_threads_enter()</code></a> should be used instead of
this macro.
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3281352"></a><h3>
<a name="GDK-THREADS-LEAVE:CAPS"></a>GDK_THREADS_LEAVE()</h3>
<a class="indexterm" name="id3281365"></a><pre class="programlisting">#define             GDK_THREADS_LEAVE()</pre>
<p>
This macro marks the end of a critical section 
begun with <a class="link" href="gdk-Threads.html#GDK-THREADS-ENTER:CAPS"><span class="type">GDK_THREADS_ENTER</span></a>.
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3281390"></a><h3>
<a name="gdk-threads-init"></a>gdk_threads_init ()</h3>
<a class="indexterm" name="id3281402"></a><pre class="programlisting">void                gdk_threads_init                    (void);</pre>
<p>
Initializes GDK so that it can be used from multiple threads
in conjunction with <a class="link" href="gdk-Threads.html#gdk-threads-enter"><code class="function">gdk_threads_enter()</code></a> and <a class="link" href="gdk-Threads.html#gdk-threads-leave"><code class="function">gdk_threads_leave()</code></a>.
<a
href="/usr/share/gtk-doc/html/glib/glib-Threads.html#g-thread-init"
><code class="function">g_thread_init()</code></a> must be called previous to this function.
</p>
<p>
This call must be made before any use of the main loop from
GTK+; to be safe, call it before <a
href="/usr/share/gtk-doc/html/gtk/gtk-General.html#gtk-init"
><code class="function">gtk_init()</code></a>.</p>
<p>

</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3281476"></a><h3>
<a name="gdk-threads-enter"></a>gdk_threads_enter ()</h3>
<a class="indexterm" name="id3281489"></a><pre class="programlisting">void                gdk_threads_enter                   (void);</pre>
<p>
This macro marks the beginning of a critical section in which GDK and
GTK+ functions can be called safely and without causing race
conditions.  Only one thread at a time can be in such a critial
section.
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3281514"></a><h3>
<a name="gdk-threads-leave"></a>gdk_threads_leave ()</h3>
<a class="indexterm" name="id3281527"></a><pre class="programlisting">void                gdk_threads_leave                   (void);</pre>
<p>
Leaves a critical region begun with <a class="link" href="gdk-Threads.html#gdk-threads-enter"><code class="function">gdk_threads_enter()</code></a>. 
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3281559"></a><h3>
<a name="gdk-threads-mutex"></a>gdk_threads_mutex</h3>
<a class="indexterm" name="id3281574"></a><pre class="programlisting">extern GMutex *gdk_threads_mutex; /* private */
</pre>
<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;">
<h3 class="title">Warning</h3>
<p><code class="literal">gdk_threads_mutex</code> is deprecated and should not be used in newly-written code.</p>
</div>
<p>
The <a
href="/usr/share/gtk-doc/html/glib/glib-Threads.html#GMutex"
><span class="type">GMutex</span></a> used to implement the critical region for
<a class="link" href="gdk-Threads.html#gdk-threads-enter"><code class="function">gdk_threads_enter()</code></a>/<a class="link" href="gdk-Threads.html#gdk-threads-leave"><code class="function">gdk_threads_leave()</code></a>. 
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3281633"></a><h3>
<a name="gdk-threads-set-lock-functions"></a>gdk_threads_set_lock_functions ()</h3>
<a class="indexterm" name="id3281649"></a><pre class="programlisting">void                gdk_threads_set_lock_functions      (<a
href="/usr/share/gtk-doc/html/gobject/gobject-Closures.html#GCallback"
>GCallback</a> enter_fn,
                                                         <a
href="/usr/share/gtk-doc/html/gobject/gobject-Closures.html#GCallback"
>GCallback</a> leave_fn);</pre>
<p>
Allows the application to replace the standard method that
GDK uses to protect its data structures. Normally, GDK
creates a single <a
href="/usr/share/gtk-doc/html/glib/glib-Threads.html#GMutex"
><span class="type">GMutex</span></a> that is locked by <a class="link" href="gdk-Threads.html#gdk-threads-enter"><code class="function">gdk_threads_enter()</code></a>,
and released by <a class="link" href="gdk-Threads.html#gdk-threads-leave"><code class="function">gdk_threads_leave()</code></a>; using this function an
application provides, instead, a function <em class="parameter"><code>enter_fn</code></em> that is
called by <a class="link" href="gdk-Threads.html#gdk-threads-enter"><code class="function">gdk_threads_enter()</code></a> and a function <em class="parameter"><code>leave_fn</code></em> that is
called by <a class="link" href="gdk-Threads.html#gdk-threads-leave"><code class="function">gdk_threads_leave()</code></a>.
</p>
<p>
The functions must provide at least same locking functionality
as the default implementation, but can also do extra application
specific processing.
</p>
<p>
As an example, consider an application that has its own recursive
lock that when held, holds the GTK+ lock as well. When GTK+ unlocks
the GTK+ lock when entering a recursive main loop, the application
must temporarily release its lock as well.
</p>
<p>
Most threaded GTK+ apps won't need to use this method.
</p>
<p>
This method must be called before <a class="link" href="gdk-Threads.html#gdk-threads-init"><code class="function">gdk_threads_init()</code></a>, and cannot
be called multiple times.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>enter_fn</code></em>&#160;:</span></p></td>
<td>   function called to guard GDK
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>leave_fn</code></em>&#160;:</span></p></td>
<td> function called to release the guard
</td>
</tr>
</tbody>
</table></div>
<p class="since">Since  2.4
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3281827"></a><h3>
<a name="gdk-threads-add-idle"></a>gdk_threads_add_idle ()</h3>
<a class="indexterm" name="id3281843"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint"
>guint</a>               gdk_threads_add_idle                (<a
href="/usr/share/gtk-doc/html/glib/glib-The-Main-Event-Loop.html#GSourceFunc"
>GSourceFunc</a> function,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gpointer"
>gpointer</a> data);</pre>
<p>
A wrapper for the common usage of <a class="link" href="gdk-Threads.html#gdk-threads-add-idle-full"><code class="function">gdk_threads_add_idle_full()</code></a> 
assigning the default priority, <a
href="/usr/share/gtk-doc/html/glib/glib-The-Main-Event-Loop.html#G-PRIORITY-DEFAULT-IDLE:CAPS"
><span class="type">G_PRIORITY_DEFAULT_IDLE</span></a>.
</p>
<p>
See <a class="link" href="gdk-Threads.html#gdk-threads-add-idle-full"><code class="function">gdk_threads_add_idle_full()</code></a>.</p>
<p>

</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td><p><span class="term"><em class="parameter"><code>function</code></em>&#160;:</span></p></td>
<td> function to call
</td>
</tr>
<tr>
<td><p><span class="term"><em class="parameter"><code>data</code></em>&#160;:</span></p></td>
<td>     data to pass to <em class="parameter"><code>function</code></em>
</td>
</tr>
<tr>
<td><p><span class="term"><span class="emphasis"><em>Returns</em></span>&#160;:</span></p></td>
<td> the ID (greater than 0) of the event source.

</td>
</tr>
</tbody>
</table></div>
<p class="since">Since  2.12
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id3281976"></a><h3>
<a name="gdk-threads-add-idle-full"></a>gdk_threads_add_idle_full ()</h3>
<a class="indexterm" name="id3281991"></a><pre class="programlisting"><a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#guint"
>guint</a>               gdk_threads_add_idle_full           (<a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gint"
>gint</a> priority,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-The-Main-Event-Loop.html#GSourceFunc"
>GSourceFunc</a> function,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Basic-Types.html#gpointer"
>gpointer</a> data,
                                                         <a
href="/usr/share/gtk-doc/html/glib/glib-Datasets.html#GDestroyNotify"
>GDestroyNotify</a> notify);</pre>