Applying a patch for a package

[Brian Rose <lists%brianrose.net@localhost>]

I am doing some embedded development, and I need to apply a patch to gdb 
in order to get it to function with some Background Debugging Monitor 
(BDM) equipment. The site on sourceforge has a .patch file that I can 
apply to gdb 5.3.

How do I go about applying the patch to the pkgsrc version of gdb. Do I 
just drop it into the patches folder (tried didn't work) or is there 
some other procedure I need to do?

Thanks in advance,

--

Brian