From mboxrd@z Thu Jan  1 00:00:00 1970
From: mascheck@in-ulm.de (Sven Mascheck)
Date: Tue, 21 Feb 2006 18:00:55 +0100
Subject: [TUHS] AT+T UNIX PC Information needed
In-Reply-To: <200602210346.WAA21487@cuzuco.com>
References: <200602210346.WAA21487@cuzuco.com>
Message-ID: <20060221170054.GX22044@lisa.in-ulm.de>

Brian S Walden wrote:
> Duncan Anderson asks:

>> Is the lack of streams the main difference between the 2 and 3?
> 
> SVR3 also added shared libraries and RFS. As for TCP/IP the popular
> implementation was from Wollongong.

A slightly awkward [1] but quite comfortable approach to
distinguish the Research/AT&T releases is identifying the shell.

New in the SVR3 shell (features easy to test):
 - "getopts" built-in
 - "read" knows the error message "missing arguments"
(- "cd" diagnostics.  Some vendors modified these again, though.
   Stock SVR3: cd formerly only knew "bad directory" and now there
   are "not a directory", "does not exist", "permission denied" and
   two diagnostics concerning remote file systems.)

[1] Not really awkward, because the introduction of shell functions
    is a quite frequently mentioned feature to identify SVR2.