Build directory in Yocto

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The build directory is created when you run source oe-init-build-env script.  Its main directories are:

  • conf : Configuration files which control poky and Bitbake. build/conf/local.conf and build/conf/bblayers.conf are present in it
  • downloads: yocto stores all the downloaded packages (Source files), including those downloaded over SVN or git or similar
  • sstate-cache: snapshost of an unaltered Yocto recipe deployed as a set of packaged data generating a cache. Bitbake checks SSTATE to see if a recipe does not need to be rebuilt, thereby saving time.
  • tmp:  temporary  build directory. We will see a lot more about tmp directory in the upcoming posts.


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