os/doc
3
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

Add documentation about opt_VARS.

Browse source 
Reviewed by:	wblock
Sponsored by:	Absolight
Differential Revision:	https://reviews.freebsd.org/D3516
This commit is contained in:
Mathieu Arnold 2015-09-09 13:01:54 +00:00
parent a3d95c7dee
commit 00d15b7791
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=47394
1 changed files with 60 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

60
en_US.ISO8859-1/books/porters-handbook/makefiles/chapter.xml
View file

@ -4429,6 +4429,66 @@ X509_PREVENTS_MSG= X509 and SCTP patches conflict</programlisting>
</example>
</sect3>
<sect3 xml:id="options-vars">
<title><varname><replaceable>OPT</replaceable>_VARS</varname>
and
<varname><replaceable>OPT</replaceable>_VARS_OFF</varname></title>
<para>Provides a generic way to set and append to
variables.</para>
<warning><para>Before using
<varname><replaceable>OPT</replaceable>_VARS</varname> and
<varname><replaceable>OPT</replaceable>_VARS_OFF</varname>,
see if there is already a more specific helper available in
<xref linkend="options-variables"/>.</para></warning>
<para>When option <replaceable>OPT</replaceable> is selected,
and <varname><replaceable>OPT</replaceable>_VARS</varname>
defined,
<literal><replaceable>key</replaceable>=<replaceable>value</replaceable></literal>
and
<literal><replaceable>key</replaceable>+=<replaceable>value</replaceable></literal>
pairs are evaluated from
<varname><replaceable>OPT</replaceable>_VARS</varname>. An
<literal>=</literal> cause the existing value of
<literal>KEY</literal> to be overwritten, an
<literal>+=</literal> appends to the value.
<varname><replaceable>OPT</replaceable>_VARS_OFF</varname>
works the same way, but when <literal>OPT</literal> is
<emphasis>not</emphasis> selected.</para>
<programlisting>OPTIONS_DEFINE= OPT1 OPT2 OPT3
OPT1_VARS= also_build+=bin1
OPT2_VARS= also_build+=bin2
OPT3_VARS= bin3_build=yes
OPT3_VARS_OFF= bin3_build=no
MAKE_ARGS= ALSO_BUILD="${ALSO_BUILD}" BIN3_BUILD="${BIN3_BUILD}"</programlisting>
<para>is equivalent to:</para>
<programlisting>OPTIONS_DEFINE= OPT1 OPT2
MAKE_ARGS= ALSO_BUILD="${ALSO_BUILD}" BIN3_BUILD="${BIN3_BUILD}"
.include &lt;bsd.port.options.mk&gt;
.if ${PORT_OPTIONS:MOPT1}
ALSO_BUILD+= bin1
.endif
.if ${PORT_OPTIONS:MOPT2}
ALSO_BUILD+= bin2
.endif
.if ${PORT_OPTIONS:MOPT2}
BIN3_BUILD= yes
.else
BIN3_BUILD= no
.endif</programlisting>
</sect3>
<sect3 xml:id="options-dependencies">
<title>Dependencies,
<varname><replaceable>OPT</replaceable>_<replaceable>DEPTYPE</replaceable></varname>