How to build optional package if certain requirement is satisfied?

["Liguo Song" <liguo song vanderbilt edu>]

Dear RPM Users,

I have a problem with packaging RPMs. The source tar ball is configured in
such a way that some optional components will be build if a certain
requirement is met. I want to package these optional components into a
separate package, which depends on the requirement.

I know of the conditional build ability, with which you can define certain
macros in the command line of rpm to control the build behavior. But, I
prefer the minimal input from my src rpm user. So, I want to automate this
procedure with something like this (pseudo codes of spec files. :)

%if required-package
%package optional-components
Summary: some optional stuff
BuildRequires: required-package
Requires: other-requirements

%files
%{_bindir}/optional-bins

Is this possible right now with rpm-4.1?

Thanks for your comments.


Liguo Song (Leo)