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OpenGL ES 1.0 and EGL 1.0 reference manual and man pages (written by
Claude Knaus, based on OpenGL SI man pages).

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook V4.2//EN" "DTD/docbook/docbookx.dtd">

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<refentry id="eglGetProcAddress">

  <refmeta>
    <refentrytitle>eglGetProcAddress</refentrytitle>
    <manvolnum>3G</manvolnum>
  </refmeta>

  <refnamediv>
    <refname>eglGetProcAddress</refname>
    <refpurpose>
      return a <acronym>GL</acronym> or an <acronym>EGL</acronym>
      extension function
    </refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <title>C Specification</title>

    <funcsynopsis>
      <funcprototype>
        <funcdef>void (* <function>eglGetProcAddress</function>)()</funcdef>
        <paramdef>char const * <parameter>procname</parameter></paramdef>
      </funcprototype>
    </funcsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>Parameters</title>

    <variablelist>
      <varlistentry>
        <term><parameter>procname</parameter></term>
        <listitem>
          <para>
            Specifies the name of the function to return.
          </para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1>
    <title>Description</title>

    <para>
      <function>eglGetProcAddress</function> returns the address of
      the extension function named by <parameter>procname</parameter>.
      <parameter>procname</parameter>
      must be a null-terminated string. The pointer returned
      should be cast to a function pointer type matching the extension
      function's definition in that extension specification. A return value
      of <constant>NULL</constant> indicates that the specific
      function does not exist for the <acronym>EGL</acronym> implementation.
    </para>

    <para>
      A non-<constant>NULL</constant> return value does not guarantee
      that an extension function is actually supported at runtime. The client
      must also query
      <citerefentry><refentrytitle>glGetString</refentrytitle></citerefentry>(<constant>GL_EXTENSIONS</constant>) or
      <citerefentry><refentrytitle>eglQueryString</refentrytitle></citerefentry>(<parameter>display</parameter>,
      <constant>EGL_EXTENSIONS</constant>) to determine if an
      extension is supported by a particular context or display.
    </para>

    <para>
      Function pointers returned by
      <function>eglGetProcAddress</function> are independent of the
      display and the currently bound context and may be used by any context
      which supports the extension.
    </para>

    <para>
      <function>eglGetProcAddress</function> may be queried for all
      <acronym>GL</acronym> and <acronym>EGL</acronym> extension functions.
    </para>
  </refsect1>

  <refsect1>
    <title>See Also</title>

    <para>
      <citerefentry><refentrytitle>glGetString</refentrytitle></citerefentry>,
      <citerefentry><refentrytitle>eglQueryString</refentrytitle></citerefentry>    </para>
  </refsect1>

</refentry>