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<h1 align="center">The VNC Protocol and Qtopia Core<br /><small></small></h1>
<p>VNC (Virtual Network Computing) software makes it possible to view and interact with one computer (the "server") from any other computer or mobile device (the "viewer") anywhere on a network.</p>
<p>To run a Qtopia Core</tt> application using the VNC protocol, the Qtopia Core</tt> library must be configured and compiled with the <tt>-qt-gfx-vnc</tt> option:</p>
<pre> cd path/to/Qtopia/Core
./configure -qt-gfx-vnc
make</pre>
<p>Then start a server application (i.e. construct a <a href="gui/QApplication.html"><tt>QApplication</tt></a> object with the QApplication::GuiServer flag or use the -qws command line parameter. See the <a href="qtopiacore-running.html">running applications</tt></a> documentation for details). When runnng the application, use the <tt>-display</tt> option to specify the VNC server's driver. For example:</p>
<pre> cd path/to/Qtopia/Core/examples/widgets/analogclock
./analogclock -qws -display VNC:0</pre>
<p>To interact with the application over the network, run a VNC client pointing to the machine that is running the server application. VNC clients are available for a vast array of display systems: X11, Windows, Amiga, DOS, VMS, and dozens of others. For example, using the X11 VNC client to view the application from the same machine:</p>
<pre> vncviewer localhost:0</pre>
<p>Qtopia Core</tt> will create a 640 by 480 pixel display by default. Alternatively, the <a href="qtopiacore-envvars.html#qws-size"><tt>QWS_SIZE</tt></a> environment variable can be used to set another size, e.g. <tt>QWS_SIZE=240x320</tt>.</p>
<p><table align="center" cellpadding="2" cellspacing="1" border="0">
<tr valign="top" class="odd"><td><b>The Virtual Framebuffer</b><p>The <a href="qtopiacore-qvfb.html">virtual framebuffer</tt></a> is an alternative technique recommended for development and debugging purposes.</p>
<p>The virtual framebuffer emulates a framebuffer using a shared memory region and the <tt>qvfb</tt> tool to display the framebuffer in a window.</p>
<p>Its use of shared memory makes the virtual framebuffer much faster and smoother than using the VNC protocol, but it does not operate over a network.</p>
</td><td><img src="images/qtopiacore-virtualframebuffer.png" /></td></tr>
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