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SimDist operates on a loose system of package configuration, which sets a number of standard build variables in the configuration stage for each package in the packages directory. A configure script in the base directory generates the actual Make file fragments for the packages, depending on the configuration selected and on the properties of the local host. Following the Autoconf build system's conventions, there are .in files in the package directories that are used by the configure script to generate these Make fragments. The configuration of individual packages is defined in the Autoconf file at build/packages.m4. This sets and substitutes the necessary variables for the build system by calling the Autoconf macro associated with each package.
Each package has a file called package.gmk, where the default settings for packages are overridden or additional settings can be added.
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