diff options
author | Scott Rifenbark <scott.m.rifenbark@intel.com> | 2014-06-02 15:57:50 +0300 |
---|---|---|
committer | Richard Purdie <richard.purdie@linuxfoundation.org> | 2014-06-18 10:30:44 +0100 |
commit | a456afa06c56dd87da74c40d886fbcc4dce20e02 (patch) | |
tree | 6158bc6cdb2ca9caf2efbf2db386b96d8bdf0e55 /documentation/dev-manual | |
parent | 84ee8c653a45ffbda1fd3773f5fbb67d20d1bfc3 (diff) | |
download | ast2050-yocto-poky-a456afa06c56dd87da74c40d886fbcc4dce20e02.zip ast2050-yocto-poky-a456afa06c56dd87da74c40d886fbcc4dce20e02.tar.gz |
dev-manual: Updates to the "Understanding Recipe Syntax" section.
Paul Eggleton sent me some feedback on this section. I implemented
his suggestions. Changes were minor. One included a cross-link
to the BitBake User Manual.
(From yocto-docs rev: e9b5f252a1368b8c231dd659428a18eacf9757af)
Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Diffstat (limited to 'documentation/dev-manual')
-rw-r--r-- | documentation/dev-manual/dev-manual-common-tasks.xml | 27 |
1 files changed, 15 insertions, 12 deletions
diff --git a/documentation/dev-manual/dev-manual-common-tasks.xml b/documentation/dev-manual/dev-manual-common-tasks.xml index 4a58a6f..6ae7730 100644 --- a/documentation/dev-manual/dev-manual-common-tasks.xml +++ b/documentation/dev-manual/dev-manual-common-tasks.xml @@ -1400,8 +1400,13 @@ <title>Understanding Recipe Syntax</title> <para> - The basic items that make up a BitBake recipe file are - as follows: + Understanding recipe file syntax is important for + writing recipes. + The following list overviews the basic items that make up a + BitBake recipe file. + For more complete BitBake syntax descriptions, see the + "<ulink url='&YOCTO_DOCS_BB_URL;#bitbake-user-manual-metadata'>Syntax and Operators</ulink>" + chapter of the BitBake User Manual. <itemizedlist> <listitem><para><emphasis>Variable Assignments and Manipulations:</emphasis> Variable assignments allow a value to be assigned to a @@ -1519,18 +1524,16 @@ <filename>local.conf</filename> file for variables that are allowed to come through from the external environment. - Doing so allows you to actually set variables from - the external environment that would otherwise be - overwritten.</para> - <para>Here is an example: + </para> + <para>Here is an example where + <filename>VAR1</filename> is set to "New value" if + it is currently empty. + However, if <filename>VAR1</filename> has already been + set, it remains unchanged: <literallayout class='monospaced'> VAR1 ?= "New value" </literallayout> - In the previous example, <filename>VAR1</filename> is - set to "New value" if it is currently empty. - However, if <filename>VAR1</filename> has already been - set, it remains unchanged.</para> - <para>In this next example, <filename>VAR1</filename> + In this next example, <filename>VAR1</filename> is left with the value "Original value": <literallayout class='monospaced'> VAR1 = "Original value" @@ -1632,7 +1635,7 @@ </literallayout> </para></listitem> <listitem><para><emphasis>Shell Function Syntax:</emphasis> - Use shell function syntax as if you were writing a shell + Write shell functions as if you were writing a shell script when you describe a list of actions to take. You should ensure that your script works with a generic <filename>sh</filename> and that it does not require |