BuildRequires: how vary depending on build host?

[Nick Urbanik <nicku vtc edu hk>]

Dear Folks,

I am writing RPM packages.  How do I write a BuildRequires statement
that depends on the version of Red Hat/Fedora of the build host?

My problem is that the package needs db3-devel on build platforms Red
Hat 7.3 and older, and needs db4-devel otherwise.  Please could anyone
suggest a macro or some sensible way of writing such a BuildRequires
statement?  I would be most grateful for any suggestions.

--
Nick Urbanik   RHCE                               nicku(at)vtc.edu.hk
Dept. of Information & Communications Technology
Hong Kong Institute of Vocational Education (Tsing Yi)
Tel:   (852) 2436 8576, (852) 2436 8713          Fax: (852) 2436 8526
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