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Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!uwm.edu!lll-winken!pacbell!att!chinet!ignatz
From: ignatz@chinet.chi.il.us (Dave Ihnat)
Newsgroups: unix-pc.uucp,comp.sys.att
Subject: Re: Machine names on the net ...
Summary: A Caveat for those trusting name truncation
Keywords: UUCP, site name lengths
Message-ID: <1990Jan15.183520.4462@chinet.chi.il.us>
Date: 15 Jan 90 18:35:20 GMT
References: <33@suntau.UUCP> <25902@cup.portal.com>
Sender: Dave Ihnat
Reply-To: ignatz@chinet.chi.il.us (Dave Ihnat)
Organization: Chinet - Chicago Public Access UNIX
Lines: 22

As has been commented earlier, the six-character limit is purely an artifact--
whether of short-sighted arbitrary design restrictions, or a laudable desire
to make sure all software was downward compatible, I choose not to judge.  But
the upshot is that, while it should be only archaic software that enforces this
limitation, many fairly recently-shipped versions of UUCP still have an
arbitrary limitation.  (Think of the thousands of Unix-PC machines!)

The reason I'm posting, however, is to warn about the side effects of assuming
truncation will produce acceptable transfers.  In particular, if a site on
which UUCP expects short names, and truncates, talks to a site which allows
long names--especially HDB UUCP--there will be a mismatch.  Assume you're site
'foobarber', and your software assumes 6-character names.  You'll appear to
the HDB site to be simply 'foobar'.  Unfortunately, if they try to enter you
in their permissions and Systems files as 'foobarber', they not only won't
truncate, but they'll reject your calls identifying you with the shorter name
unless you have them modify the Permissions file entries.  Also, in some cases,
I've seen versions of "short-name" UUCP reject the long names sent by HDB.
Even though the software only expects 6-character names, it seemed to still
compare on the longer incoming name's full length.

In short, you may well be introducing some fragility if you rely on name-length
truncation.