[yocto] Preventing a variable from being cached

[Alexander Kanavin]

On 12/07/2017 10:22 PM, Paul Knopf wrote:
> I have all my meta-layers and build conf files checked into a single 
> repository (submodules for layers). I want a recipe to look at the git 
> repository, and place a file in the build. I'd like this repository to 
> read the HEAD, and decide if it needs to be rebuilt (to put new file in 
> image) based off of HEAD/branch location.


Use the file: fetcher for the file in SRC_URI, and the fetcher will 
detect if the file has changed and trigger a rebuild accordingly.

Alex