Standards Update, IEEE 1003.1: System services interface

[Doug Gwyn]

From:  Doug Gwyn <gwyn at smoke.brl.mil>

>There was a discussion about whether it is possible (and preferable)
>to improve the low-level directory interfaces instead of adding new,
>high-level interfaces.  Do the high-level interfaces really add new
>functionality for portable applications?  Do they belong with the
>low-level operating system interfaces specified in 1003.1?

No, definitely not.  However, they would be appropriate at the 1003.2
level.  Note that 1003.2 implementations are not constrained to use
only 1003.1 facilities, so the fact that it's hard to implement tree
walkers right using the existing 1003.1 directory access functions is
no argument against defining tree walkers as part of a higher level.

>The ISO POSIX group (JTC1/SC22/WG15) pointed out that both of these
>[tar, cpio] formats are incompatible with accepted international and U.S.
>standards.  After some arm twisting, the 1003.1 working group agreed
>to devise a new data interchange format based on IS 1001: 1986, which
>is more or less equivalent to ANS X3.27-1987, the familiar ANSI
>labeled tape format.

The ANSI magtape format is simply inappropriate.  UNIX archives were
designed to be single files, making it simple to transport them by
means other than magnetic tape.  In this modern networked world, for
the most part magnetic tape is an anachronism.  Any archive format
standard for UNIX should not depend on the archive supporting
multiple files, tape marks, or any other non-UNIX concept.

It is to the credit of UNIX's original designers that they did NOT
blindly adopt existing standards when they were technically inferior.
Let's not make the POSIX standards impose conventional-think upon
UNIX environments..

Volume-Number: Volume 20, Number 69