There is always this $(VERSION) variable that I did not know how to set. Recently, apt-get update has been failing to get some repomd (repository meta-data) files, and I realized the $(VERSION) was expanding to 9.90.
Of course the repositories did not have a directory called 9.90, there was 7, 8, 9, but no decimals.
Getting off my lazy bum to do some research at long last (I was replacing $(VERSION) with 9 manually), I found http://apt-rpm.org/options.shtml which documented two variables in the APT:: namespace - DistroVersion and DistroVerPkg.
In the first place, this information should have been more up-front and visible in the documentation. Googling "apt-get $(VERSION)" didn't turn up any good hits at all.
DistroVerPkg is the default value for deriving $(VERSION), and it has a value of "fedora-release" (/etc/fedora-release). This file looks like this:
Fedora release 9.90.1 (Rawhide)This causes $(VERSION) to expand by default to 9.90, since DistroVersion is not defined.
Hence, in my /etc/apt.conf, I've added the following line:
APT::DistroVersion "9";
which expands $(VERSION) to the correct value.
