This directory holds the package descriptions for the Fink distribution. When you're reading this in an installed Fink tree, it also holds the binary package files of any packages you have built locally. The basic structure is the same as that of a Debian GNU/Linux mirror. This is because Fink uses Debian's tools (dpkg, apt) for binary package management.
Currently, the package descriptions are held in fink's github repository. There are three ways for them to get from git into your Fink tree.
The first way is to download a tarball, unpack it in a temporary directory and use the provided inject.pl script. The script copies the description files into your Fink installation. Just run it, in most cases it locates your tree on its own. If it doesn't, pass the path as a parameter, as in
./inject.pl /sw
The second way is basically the same, but instead of downloading a tarball, you use git to check out the 'fink-distributions' repository to a temporary directory. Then you use the inject.pl script as above.
The third way is to access git directly. This requires some one-time setup work, but is quite convenient thereafter. Unfortunately there is no script to do the one-time setup yet. You need to check out the 'packages' module to the directory /sw/fink. Before you can do that, you must move the existing /sw/fink directory out of the way, or git will fail. Afterwards, you must merge both directories together, to get the 'local' directory and the already built packages back.
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