[Fedora-packaging] Checking distro release from spec file

[Ray Van Dolson]

I'm trying to write a "distro agnostic" spec file that will apply two
patches:

  - Patch 1 if and only if we're building for EL5 or EL4
  - Patch 2 if and only if we're building for EL4

I know I can check for EL with the presence of the %{fedora} macro, but
is there a "right" way to check the EL version short of calling rpm -q
redhat-release?  I don't see a macro defined for this in /etc/rpm.

I guess I could operate on the dist tag...

Ray