[yocto] How to recreate rootfs image

[Lenivyy Viktor]

> The assumption is that you wouldn't normally be fetching the source from a
> local path as you are, you would fetch it from some repository (though that
> repository may be internal to your organisation). At some point you run
> "devtool modify" which is effectively a way of saying "I want to start working on
> the source for this particular recipe in this location" - at which point either
> you're specifying an existing source checkout that you've prepared, or you
> specify -x and it prepares it for you. Having run that, the fetch/unpack tasks are
> disabled, and the specified external source tree will be used in the build.
> Additionally, that external source tree is yours to keep should you wish - it will
> never be deleted by the build system; the same *cannot* be said of the build
> system's temporary source checkout under tmp/work - your work in progress
> can be lost in an instant if you run -c clean or have rm_work enabled. There
> really are two different modes here - normal build, where you want the sources
> as anyone else building the system would fetch, and development, where you
> want your own sources that you are in control of.
> 
Thank you for detailed answer, Paul. It needs to be added to documentation.