
<refentry id="glXImportContextEXT">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>1991-2006</year>
                <holder>Silicon Graphics, Inc.</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>glXImportContextEXT</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glXImportContextEXT</refname>
        <refpurpose>import another process's indirect rendering context.</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>GLXContext <function>glXImportContextEXT</function></funcdef>
                <paramdef>Display * <parameter>dpy</parameter></paramdef>
                <paramdef>GLXContextID <parameter>contextID</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <!-- eqn: ignoring delim $$ -->
    <refsect1 id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>dpy</parameter></term>
            <listitem>
                <para>
                    Specifies the connection to the X server.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>contextID</parameter></term>
            <listitem>
                <para>
                    Specifies a GLX rendering context.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>glXImportContextEXT</function> creates a GLXContext given the XID of an existing GLXContext.
            It may be used in place of <citerefentry><refentrytitle>glXCreateContext</refentrytitle></citerefentry>,
            to share another process's indirect rendering context.
        </para>
        <para>
            Only the server-side context information can be shared between
            X clients; client-side state, such as pixel storage modes,
            cannot be shared. Thus, <function>glXImportContextEXT</function> must allocate memory to store
            client-side information. This memory is freed by calling
            <citerefentry><refentrytitle>glXFreeContextEXT</refentrytitle></citerefentry>.
        </para>
        <para>
            This call does not create a new XID.  It merely makes an
            existing object available to the importing client (Display *).
            Like any XID, it goes away when the creating client drops its
            connection or the ID is explicitly deleted. Note that this is
            when the XID goes away. The object goes away when the XID
            goes away AND the context is not current to any thread.
        </para>
        <para>
            If <parameter>contextID</parameter> refers to a
            direct rendering context then no error is generated but
            <function>glXImportContextEXT</function> returns NULL.
        </para>
        <para>
            <function>glXImportContextEXT</function> is part of the <code>EXT_import_context</code> extension,
            not part of the core GLX command set. If _glxextstring(EXT_import_context)
            is included in the string returned by <citerefentry><refentrytitle>glXQueryExtensionsString</refentrytitle></citerefentry>,
            when called with argument <constant>GLX_EXTENSIONS</constant>,
            extension <code>EXT_import_context</code> is supported.
        </para>
    </refsect1>
    <refsect1 id="errors"><title>Errors</title>
        <para>
            <constant>GLXBadContext</constant> is generated if <parameter>contextID</parameter> does not
            refer to a valid context.
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glXCreateContext</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glXQueryVersion</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glXQueryExtensionsString</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glXGetContextIDEXT</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glXFreeContextEXT</refentrytitle></citerefentry>
        </para>
    </refsect1>
    <refsect1 id="Copyright"><title>Copyright</title>
        <para>
            Copyright <trademark class="copyright"></trademark> 1991-2006
            Silicon Graphics, Inc. This document is licensed under the SGI
            Free Software B License. For details, see
            <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
        </para>
    </refsect1>
</refentry>
