Chased Revision: 1.729

	<sect2 id="using-scons">

	  <title>Using <command>scons</command></title>

	  <para>If your port uses <application>SCons</application>, define

	    <literal>USE_SCONS=yes</literal>.</para>

	  <table frame="none">

	    <title>Variables for ports that use <command>scons</command></title>

	    <tgroup cols="2">

	      <thead>

		<row>

		  <entry>Variable</entry>

		  <entry>Means</entry>

		</row>

	      </thead>

	      <tbody>

		<row>

		  <entry><makevar>SCONS_ARGS</makevar></entry>

		  <entry>Port specific SCons flags passed to the SCons

		    environment.</entry>

		</row>

		<row>

		  <entry><makevar>SCONS_BUILDENV</makevar></entry>

		  <entry>Variables to be set in system environment.</entry>

		</row>

		<row>

		  <entry><makevar>SCONS_ENV</makevar></entry>

		  <entry>Variables to be set in SCons environment.</entry>

		</row>

		<row>

		  <entry><makevar>SCONS_TARGET</makevar></entry>

		  <entry>Last argument passed to SCons, similar to

		    <makevar>MAKE_TARGET</makevar>.</entry>

		</row>

	      </tbody>

	    </tgroup>

	  </table>

	</sect2>

    <sect1 id="using-wx">

      <title>Using wxWidgets</title>

      <para>If your port uses <application>wxWidgets</application>

	cross-platform toolkit, define <literal>USE_WX=yes</literal>.

	A specific version can be requested by setting

	<literal>USE_WX=2.6</literal>.  Ranges (<literal>2.4-2.6</literal>)

	and partial ranges (<literal>-2.4</literal>, <literal>2.6+</literal>)

	are also possible.</para>

      <para>List of required wxWidgets components can be set as

	<makevar>WX_COMPS</makevar>.  Unless specified otherwise, port will

	depend on wxWidgets library (<literal>wx</literal>).  Available

	components are:</para>

      <table frame="none">

	<title>Possible values for <makevar>WX_COMPS</makevar></title>

	<tgroup cols="2">

	  <thead>

	    <row>

	      <entry>Value</entry>

	      <entry>Means</entry>

	    </row>

	  </thead>

	  <tbody>

	    <row>

	      <entry><literal>wx</literal></entry>

	      <entry>wxWidget libraries</entry>

	    </row>

	    <row>

	      <entry><literal>contrib</literal></entry>

	      <entry>wxWidget contributed libraries</entry>

	    </row>

	    <row>

	      <entry><literal>python</literal></entry>

	      <entry>wxPython</entry>

	    </row>

	    <row>

	      <entry><literal>mozilla</literal></entry>

	      <entry>wxMozilla (only available for 2.4)</entry>

	    </row>

	    <row>

	      <entry><literal>svg</literal></entry>

	      <entry>wxSVG (only available for 2.6)</entry>

	    </row>

	  </tbody>

	</tgroup>

      </table>

      <para>If locating wxWidget libraries needs a configure argument in

	addition to the <makevar>WX_CONFIG</makevar> variable, define

	<makevar>WX_CONF_ARGS</makevar> in your port.  Possible values

	are <literal>absolute</literal> resulting in

	<literal>--with-wx-config=${WX_CONFIG}</literal>, and

	<literal>relative</literal> resulting in

	<literal>--with-wx=${X11BASE}</literal> being added to configure

	script arguments.</para>

      <para>Define <literal>WX_UNICODE=yes</literal> if your port needs

	the Unicode version of the wxWidgets libraries.</para>

      <para>Example of port requiring Unicode versions of wxWidgets 2.6 and

	contrib libraries:</para>

      <programlisting>USE_WX=      2.6

WX_COMPS=    wx contrib

WX_UNICODE=  yes</programlisting>

    </sect1>

      <sect1 id="dads-sysctl">

	<title><filename>sysctl</filename> 使用時機</title>

	<para><filename>sysctl</filename> 除了在 targets 之外，都不鼓勵使用。

	  這是因為任何 <literal>makevar</literal> 

	  的評估都有可能會使得程序執行速度變慢。例如在

	  <command>make index</command> 的過程中就會需要用到

	  <filename>sysctl</filename>。</para>

	<para>在 <filename>sysctl</filename> 的使用上，一定要用完整的路徑，

	  也就是以 <filename>/sbin/</filename> 開頭，因為有些使用者也許沒有

	  將 <filename>/sbin/</filename> 放置在他們的環境變數 

	  <envar>PATH</envar> 中。</para>

      </sect1>