Re: usage message for newer-mtime in tar 1.13

[Eli Zaretskii]

> From: "Mark Moraes" <address@hidden>
> Date: Thu, 6 Dec 2001 18:47:10 -0800
> 
> 2. Should -N and its usage message really be conditional on !MSDOS?
> All MSDOS that I'm familiar with have an mtime in their stat()
> structures.

The fact that -N is disabled on MS-DOS is indeed a case of bad
breakage, but please note that the current 1.13 series of GNU Tar
don't support MS-DOS (and MS-Windows, for that matter) at all.  There
are quite a few serious problems with some Tar features if the code is
compiled unchanged on DOS/Windows machines, and -N is not the most
serious of them.

As an example, consider the fact that many DOS/Windows filesystems
record mtime with a 2-second granularity.  Figuring out the effects of
this on -N, --diff, and similar Tar features is left as an exercise
for the readers ;-)

A port of GNU Tar 1.12a to DOS/Windows was done in the past (by yours
truly), but the changes are not yet rolled back into 1.13, since 1.13
is based on sources that were forked before 1.12a was produced by the
previous maintainer of GNU Tar.  If you are interested, or are in the
need of a Posix-compatible Tar port for DOS/Windows, you can find it
here:

  ftp://ftp.simtel.net/pub/simtelnet/gnu/djgpp/v2gnu/tar112ab.zip

See the file README.dos there for a list of problems in the original
code that this port solves.