[yocto] Support for writable files with a read-only root file system

[Jens Rehsack]

Am 28.11.2014 um 14:51 schrieb Anders Darander <anders at chargestorm.se>:

> * Matt Schuckmann <Matt.Schuckmann at planar.com> [141126 18:22]:
>> Yes you are correct I want a small number of files into to reside in a
>> writeable partition with links in the root file system to point to
>> them. I guess I latched on to the volatiles mechanism because it seems
>> close to meeting my needs.
> 
> The volatile-binds from meta-ro-rootfs can be used to handle exactly
> this. (I.e. they doesn't have to point to tmpfs).
> 
> The 3rd alternative is the old classical approach of using a symbolic
> links...

In our project we mix the usage of volatiles, symblic links and unionfs.
You can take a look into https://github.com/rehsack/meta-jens (or
https://github.com/rehsack/yocto-builddir/tree/master/conf for other
used layers) to get a picture.

All used utilities for basic results (minimal image ...) like mkimgs,
flash-device.sh for burning mmc's from nfs boot etc. are included.

I think that should work with branches before daisy as well.

Good luck
-- 
Jens Rehsack
rehsack at gmail.com