Re: .LOW_RESOLUTION_TIME

[Eli Zaretskii]

> Date: Wed, 10 Nov 2010 08:52:05 +0330
> From: ali hagigat <address@hidden>
> 
> Sorry but one sentence of the document does not make sense related to
> Eli's example as it is saying:
> 
> "The high resolution file time stamps of many modern file systems
> lessen the chance of make incorrectly concluding that a file is up to
> date."
> 
> The time-stamp of 'src' is like 10:25:32.890 and 'dst' is 10:25:32.
> So 'src' is newer than 'dst' and 'dst' needs to be updated and make
> concludes that the file is out of date!!

The manual is correct, but it has in mind a different situation, not
the one after copying a file with a version of `cp' which loses
sub-second time resolution.

The situation the manual has in mind here is when a file is updated
within several milliseconds or several tens of milliseconds.  (This is
possible with today's powerful CPUs.)  If the filesystem only holds
the times to the nearest second, the updated file will look to Make as
if its time stamp didn't change, and the files for which this file is
a prerequisite will look up to date, whereas they really aren't.