OE working style

[Cliff Brake]

On Sun, Mar 16, 2008 at 8:56 AM, Javi Roman <javiroman at kernel-labs.org> wrote:
> On Sat, Mar 15, 2008 at 10:27 AM, Javi Roman <javiroman at kernel-labs.org> wrote:
>  > Hi everybody.
>  >
>  >  I'm building a custom OE image by means of local overlay technique, so
>  >  I'm faced with a dilemma: I have to modify any rootfs files within the
>  >  final image, such as /etc/xorg.conf, /etc/profile, and many others. I
>  >  wonder which is the correct way to personalize those files: have I
>  >  modify the original bitbake packages (be means patchs in the local
>  >  overlay)?
>  >
>  >  Please, can anybody advice me about the most habitual behaviour?
>
>
>  It could be a possibility to make a package to add the boot scripts
>  /sbin/unconfigured.sh and /sbin/setup.sh for the "firstboot" time,
>  something like "firstboot_1.0.0.bb", but I don't know if it is a clean
>  solution, and I wonder if I am reinventing the wheel.

Hello Javi,

There are a number of ways to manage changes to packages in OE and
there are tradeoffs.

1) create an overlay, and copy the package you want to modify to the
overlay.  This works pretty well and is clean, but over time it is
difficult to keep track of what files you modified if you do not take
notes, etc.

2) make the changes in a source control system.  This has been on my
list of things to try, but I have not done it with monotone yet and
will probably wait to see if the project switches SCM before putting
any time into this approach.

3) create a package that gets installed last that overwrites files
installed by other packages.  This works pretty well, and is easy, so
this is the approach I've been using lately.  Note, this is probably
not the best approach for systems you want to upgrade using ipkg, but
for what I do, if we ever update an embedded system in the field, the
entire rootfs gets updated so this is not a big issue.  You can force
your custom package to get installed last by creating a custom image
(http://bec-systems.com/web/content/view/79/9/) and adding the custom
config files package to the end of the IMAGE_INSTALL list.  Note, this
is a hack, but for me it works well for generating images for custom
embedded systems.

4) if your machine is supported in the OE, then the best solution is
to add the config files to the packages (files/<machine>).

Once the SCM situation is figured out, I would really like to start
managing all custom changes to the OE meta data using the SCM.

This issue has also been discussed at length in the past, so if you
dig in the archives you'll find some more discussion.  I don't have
any pointers to them offhand.

Cliff

-- 
=======================
Cliff Brake
http://bec-systems.com