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<?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>glXQueryContext</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glXQueryContext"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glXQueryContext — query context information</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">int <b class="fsfunc">glXQueryContext</b>(</code></td><td>Display *  </td><td><var class="pdparam">dpy</var>, </td></tr><tr><td> </td><td>GLXContext  </td><td><var class="pdparam">ctx</var>, </td></tr><tr><td> </td><td>int  </td><td><var class="pdparam">attribute</var>, </td></tr><tr><td> </td><td>int *  </td><td><var class="pdparam">value</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>dpy</code></em></span></dt><dd><p>
                    Specifies the connection to the X server.
                </p></dd><dt><span class="term"><em class="parameter"><code>ctx</code></em></span></dt><dd><p>
                    Specifies a GLX rendering context.
                </p></dd><dt><span class="term"><em class="parameter"><code>attribute</code></em></span></dt><dd><p>
                    Specifies that a context parameter should be retrieved.  Must be one of
                    <code class="constant">GLX_FBCONFIG_ID</code>, <code class="constant">GLX_RENDER_TYPE</code>, or <code class="constant">GLX_SCREEN</code>.
                </p></dd><dt><span class="term"><em class="parameter"><code>value</code></em></span></dt><dd><p>
                    Contains the return value for <em class="parameter"><code>attribute</code></em>.
                </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
            <code class="function">glXQueryContext</code> sets <em class="parameter"><code>value</code></em> to the value of <em class="parameter"><code>attribute</code></em> with respect to <em class="parameter"><code>ctx</code></em>.
            <em class="parameter"><code>attribute</code></em> may be one of the following:
        </p><div class="variablelist"><dl><dt><span class="term"><code class="constant">GLX_FBCONFIG_ID</code></span></dt><dd><p>
                        Returns the XID of the GLXFBConfig associated with <em class="parameter"><code>ctx</code></em>.
                    </p></dd><dt><span class="term"><code class="constant">GLX_RENDER_TYPE</code></span></dt><dd><p>
                        Returns the rendering type supported by <em class="parameter"><code>ctx</code></em>.
                    </p></dd><dt><span class="term"><code class="constant">GLX_SCREEN</code></span></dt><dd><p>
                        Returns the screen number associated with <em class="parameter"><code>ctx</code></em>.
                    </p></dd></dl></div><p>
            <code class="constant">Success</code> is returned unless <em class="parameter"><code>attribute</code></em> is not a valid GLX
            context attribute, in which case <code class="constant">GLX_BAD_ATTRIBUTE</code> is returned.
        </p><p>
            This call may cause a round-trip to the server.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
            <code class="function">glXQueryContext</code> is available only if the GLX version is 1.3 or greater.
        </p><p>
            If the GLX version is 1.1 or 1.0, the GL version must be 1.0.
            If the GLX version is 1.2, then the GL version must be 1.1.
            If the GLX version is 1.3, then the GL version must be 1.2.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
            <code class="constant">GLXBadContext</code> is generated if <em class="parameter"><code>ctx</code></em> does not
            refer to a valid context.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="glXCreateNewContext.xml"><span class="citerefentry"><span class="refentrytitle">glXCreateNewContext</span></span></a>,
            <a class="citerefentry" href="glXGetCurrentContext.xml"><span class="citerefentry"><span class="refentrytitle">glXGetCurrentContext</span></span></a>,
            <a class="citerefentry" href="glXQueryVersion.xml"><span class="citerefentry"><span class="refentrytitle">glXQueryVersion</span></span></a>,
            <a class="citerefentry" href="glXQueryExtensionsString.xml"><span class="citerefentry"><span class="refentrytitle">glXQueryExtensionsString</span></span></a>
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
            Copyright <span class="trademark"></span>© 1991-2006
            Silicon Graphics, Inc. This document is licensed under the SGI
            Free Software B License. For details, see
            <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
        </p></div></div></body></html>
