Michael Salmon [[EMAIL PROTECTED]] writes:

> The timestamp on fat/vfat systems is the actual time and date which
> means that there was only 5 bits left for the seconds so it has a
> granularity of 2 seconds. Interestingly the only place I could find
> this documented was in the samba source code.

For what it's worth, I just ran into this under NT as well, and
thought the following excerpt from docs for the Win32 GetFileTime call
might be useful:

  Note: Not all file systems can record creation and last access time
  and not all file systems record them in the same manner. For
  example, on Windows NT FAT, create time has a resolution of 10
  milliseconds, write time has a resolution of 2 seconds, and access
  time has a resolution of 1 day (really, the access date). On NTFS,
  access time has a resolution of 1 hour. Therefore, GetFileTime may
  not return the same file time information set using the SetFileTime
  function. Furthermore, FAT records times on disk in local
  time. However, NTFS records times on disk in UTC, so it is not
  affected by changes in time zone or daylight saving time.

The GetFileTime function is documented for all of Win95/98/NT, but the
commentary above doesn't explicitly cover 95/98, although for FAT it would
make sense to be similar.

rsync uses "write time" (modification) for its decision making
process, so even under NT and even with NTFS (which surprised me)
you've got a 2s granularity.

The bit about NTFS storing in UTC seems to me to also have the
potential to cause problems at some point but I haven't been able to
test yet (we push to FAT systems in the field).  I'm not quite certain
what would happen if rsync retrieved a time from an EST NTFS file
(which it sounds like converts from UTC to local time), then transmits
that time_t over to the remote system (say a PST NTFS file).  It would
be ok unless one of the timezones had to change, in which case the
files would seem out of whack, if I'm thinking about it correctly.

-- David

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