[yocto] writeup on the mechanics of FILESEXTRAPATHS and bbappend files

[Gary Thomas]

On 2013-04-17 16:26, Trevor Woerner wrote:
> On Wed, Apr 17, 2013 at 11:12 AM, Gary Thomas <gary at mlbassoc.com> wrote:
>> I also think it would be good to point out the use of := in the
>> FILESEXTRAPATHS
>> assignment and why it's important.
>
> Knowing that the := operator will put your directories first is only
> useful if you also know that the underlying mechanism will take the
> first such files from the given directories it encounters :-) What's
> to say bitbake doesn't look at all the directories/files and take the
> last ones?

This has more to do with how the path is constructed (using _prepend).

My point, which was totally unclear to me when using this line, was
that with ':=' ${THISDIR} evaluates to the directory that contains
the .bbappend file (what you want/need) whereas with '=' it evaluates
to the directory containing the main .bb file.  Incredibly confusing
if you miss it...

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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