Subject: Re: don't generate non-portable archives by default!
To: der Mouse <mouse@Rodents.Montreal.QC.CA>
From: Greg A. Woods <>
List: tech-userlevel
Date: 10/16/2002 14:36:15
[ On Wednesday, October 16, 2002 at 19:17:24 (+0200), der Mouse wrote: ]
> Subject: Re: don't generate non-portable archives by default!
> > If users really do need the ability to store files which cannot
> > currently be portably represented in strict IEEE Std 1003.1-1990
> > compliant archives then the way to help them is to implement the new
> > POSIX 1003.2b (-2001?) extensions.
> Whee!  Excellent.  Thank you.  I've been looking for *ages* for
> something, anything, more than historical practice as to what
> constituted a valid tar archive.
> Now all I have to do is find copies of those specs. :-/

The drafts are still available here:

The final version is available as the core to "The Single UNIX
Specification Version 3" from:

or more specifically you register for download here:

The standard 'ustar Interchange Format' is described in the file
utilities/pax.html (at #tag_04_100_13_06), as is the new 'pax
Interchange Format' and the 'cpio Interchange Format'

In the "Rationale" section of that same file in SuSv3 you'll find a
history of the decisions made about these formats too, but to really go
back to how 'ustar' itself (and 'cpio' too) got started you'd have to
get the original IEEE Std 1003.1-1990 (or ISO/IEC 9945-1:1990) and read
whatever rationale it contains.

								Greg A. Woods

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