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From: mark@cbosgd.UUCP (Mark Horton)
Newsgroups: net.news.adm,net.news.sa,net.sources.d
Subject: Re: Beware of Blindly Un-SHARing a File
Message-ID: <2039@cbosgd.UUCP>
Date: Tue, 22-Apr-86 00:49:15 EST
Article-I.D.: cbosgd.2039
Posted: Tue Apr 22 00:49:15 1986
Date-Received: Wed, 23-Apr-86 21:21:13 EST
References: <947@kitty.UUCP> <2407@prls.UUCP> <1439@garfield.columbia.edu>
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In article <243@mrstve.UUCP> rjk@mrstve.UUCP (Richard Kuhns) writes:
>
>Am I being naive in suggesting that cpio be used?  While ar-archives are
>not necessarily compatible between different machines (most obvious to me
>when I tried to move an ar-archive from an AT&T 3b2 to a 3b1), ASCII cpio
>archives seem to travel OK.  In addition, it would be fairly simple to
>extract files from the archive, as follows:
>
Seems like a good idea, but cpio won't work.  Some problems:

cpio files are not necessarily vanilla ASCII text, so mailers can step
on them.

cpio files are sensitive to the exact byte counts, so the hand editing
that has to be done (e.g. removing headers) might mess it up.  The
editor might alter the image a bit too.

Not all versions of UNIX come with cpio.  4.2BSD doesn't have it (because
it wasn't in 32V, so Berkeley isn't allowed to include it unless they
check that you have a System III or V license.)  Sun's UNIX comes with
a cpio command which doesn't work.  Some older cpio's don't support the
-c option.  NOBODY defaults to -c, so users would be confused.

Similar arguments can be made for/against tar, which at least has the
power of the P.1003 standard behind it.  But it seems that the 3B2
and PC/IX don't come with tar, for some unimaginable reason.  Everything
else does, at least so far.

Also, ar archives actually ARE portable among machines running genuine
SVr2, 4BSD, or V8.  Evidently the 3B1 isn't fully SVr2 compatible.