AFAIK:

* cvs co sets the modification date (and record in CVS/Entries)
  to the modification date of the file on repository
* cvs update sets the modification date (and record in CVS/Entries)
  to the date when the cvs update was run (i.e. date/time when
  cvs update changed the local file).

Take care,

Jaromir 

Robert Elz wrote:
> The subject doesn't refer to running make with -j N (N > 1) or
> any short term race conditions like that, but the long term
> slow race condition that occurs with a sequence like
> 
> 	I check out sources (anoncvs, sup, tarballs, shouldn't matter).
> 
> 	Time passes
> 
> 	Someone changes the sources (updates them) - esp when an
> 		include file (which will go in /usr/include/* is updated)
> 	
> 	Time passes
> 
> 	I "make build" (method by which that's done isn't important).
> 	Success, no problems.
> 
> 	Time passes
> 
> 	I update my sources because of some new feature that's now included
> 
> 	I "make build" (again, method of doing this doesn't matter, the
> 	problems aren't related to the new toolchain, or build mechanisms)
> 
> 	Crash & burn
-- 
Jaromir Dolecek <jdolecek@NetBSD.org> http://www.NetBSD.org/Ports/i386/ps2.html
-=- We should be mindful of the potential goal, but as the tantric    -=-
-=- Buddhist masters say, ``You may notice during meditation that you -=-
-=- sometimes levitate or glow.   Do not let this distract you.''     -=-