the build and execution environment.
This is very useful. For example, it allows packages built on a SuSE
8.2 system to run on a SuSE 8.1 system (this is because 8.2 has a newer
glibc; packages built against it cannot be dynamically linked against
older glibcs).
Of course, Fix packages should not directly import glibc since that is
very system-specific. Rather, they should import stdenv/stdenv.fix and
in their build scripts source in $stdenv/setup, which will setup the
right environment variables. The idea is that stdenv.fix provides the
basic C/Unix build environment (C compiler, POSIX utilities, etc.).
Note that only the ATerm package currently uses this.
svn path=/nixpkgs/trunk/; revision=203