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Each release consists of a number of packages with a specific version number.  The release itself has its own version number.  When a user creates their own release and package within this release, the modules they build will be a mix of code in their release directory, as well as libraries from the system release directory.  As new releases are added to the system, the SconsTools package (which scons invokes) must maintain consistency between the code in the local user release directory, and the system release.  To upgrade the version of a release, see Typical development tasks.

The release directory will have a SConscript file, as will each package subdiretory.  The structure of a release directory is explained in this page about Packages and Releases. Run scons from the release directory. The top level SConscript file is responsible for building and installing software in each package directory. Software is installed in the release/arch subdirectory.

External Libraries and Scons Build Customization

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