diff options
| author | Theodore A. Roth <taroth@gmail.com> | 2009-03-02 12:08:09 -0800 |
|---|---|---|
| committer | Richard Purdie <rpurdie@linux.intel.com> | 2010-02-10 16:25:35 +0000 |
| commit | bf6a4fd658a3c07edd4565c6a139537fa10fd456 (patch) | |
| tree | 85cd6e1d244732cd87d9d5d5df7f21a256217bef /bitbake | |
| parent | 6ae39074331d7296a7516a63e2e7ce435bc5559d (diff) | |
| download | openembedded-core-bf6a4fd658a3c07edd4565c6a139537fa10fd456.tar.gz openembedded-core-bf6a4fd658a3c07edd4565c6a139537fa10fd456.tar.bz2 openembedded-core-bf6a4fd658a3c07edd4565c6a139537fa10fd456.zip | |
bitbake: usermanual.xml: Add section for ?= var setting.
(Bitbake rev: df8309c11a43a9488ca25ec114a2dd3d49b041ff)
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
Diffstat (limited to 'bitbake')
| -rw-r--r-- | bitbake/doc/manual/usermanual.xml | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/bitbake/doc/manual/usermanual.xml b/bitbake/doc/manual/usermanual.xml index cdd05998a5..c3403449fe 100644 --- a/bitbake/doc/manual/usermanual.xml +++ b/bitbake/doc/manual/usermanual.xml @@ -89,6 +89,11 @@ share common metadata between many packages.</para></listitem> <para>This results in <varname>A</varname> containing <literal>aval</literal> and <varname>B</varname> containing <literal>preavalpost</literal>.</para> </section> <section> + <title>Setting a default value (?=)</title> + <para><screen><varname>A</varname> ?= "aval"</screen></para> + <para>If <varname>A</varname> is set before the above is called, it will retain it's previous value. If <varname>A</varname> is unset prior to the above call, <varname>A</varname> will be set to <literal>aval</literal>.</para> + </section> + <section> <title>Immediate variable expansion (:=)</title> <para>:= results in a variable's contents being expanded immediately, rather than when the variable is actually used.</para> <para><screen><varname>T</varname> = "123" |