Document for how to work with patches?

[Craig Rodrigues]

Hi,

Is there a FreeBSD document somewhere that explains how to
work with patches?  As experienced FreeBSD developers, we often take
this for granted, but a lot of newbies do not.
Something that explains how to create a patch, how to apply a patch, etc.
would be useful.  It would actually be useful to have this, not just
for FreeBSD, but for other open source projects.
  
-- 
Craig Rodrigues        
rodrigc at crodrigues.org