Re: clock skews

[Paul D. Smith]

%% Regarding clock skews; you wrote:

  ds> My client has the following clock skew error message using our
  ds> product , which includes GMAKE. The skew is only about two seconds
  ds> but is understandably annoying to the customer. I am unable to
  ds> duplicate the problem in the lab and suspect it is related to his
  ds> system clock being out of synch when our product, vdsp, was
  ds> installed. He was playing about with the daylight saving tick box
  ds> in the system tray around the time of the installation. Have you
  ds> seen anything like this before? I should clarify at the outset
  ds> that he is using one PC and is not sharing files with any other.
  ds> All the files are in the same PC at all times. I looked at your
  ds> documentation web page but couldn't see anything. I would be
  ds> grateful if you could point me in the right direction.

What operating system is running on the PC?

If it's Windows, then what filesystem (FAT or NTFS) is the client using?

It turns out that FAT-based filesystems cannot store timestamps with
single-second granularity; they only store timestamps with two or three
second granularity.

There is a workaround in the later versions of GNU make that tries to
take this into account, by ignoring skews that are within a certain
amount of time.

  ds> gmake-378: *** Warning: File `parser.c' has modification time in the 
future
  ds> (2001-07-12 10:51:28 > 2001-07-12 10:51:26)
  ds> gmake-378: *** Warning:  Clock skew detected.  Your build may be 
incomplete.
  ds> No valid command(s) to build.

I'm assuming that parser.c is a generated file.

-- 
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 Paul D. Smith <address@hidden>          Find some GNU make tips at:
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