Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!seismo!caip!clyde!cbatt!cbosgd!ucbvax!BU-CS.BU.EDU!root
From: root@BU-CS.BU.EDU (Ra)
Newsgroups: mod.protocols.tcp-ip
Subject: Re: Formatting Query
Message-ID: <8609121649.AA05920@bu-cs.bu.edu>
Date: Fri, 12-Sep-86 12:49:01 EDT
Article-I.D.: bu-cs.8609121649.AA05920
Posted: Fri Sep 12 12:49:01 1986
Date-Received: Sun, 14-Sep-86 04:02:40 EDT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The ARPA Internet
Lines: 35
Approved: tcp-ip@sri-nic.arpa

To add my 2c:

1. I am not sure about the definition of "commonly used" but
IBM Mainframes (EBCDIC) generally do not interpret tabs the
way full-duplex systems use them (not that you can't simulate
them, but it tends to be more variable in interpretation, if
at all, software application dependant.)

2. Sending files through mail via heterogenous systems is fraught
with peril although it usually works well enough if it's just text
meant to be used as text (eg. a fortran program with embedded tabs
may not compile at all when sent to an IBM system, I don't remember
for sure, but I wouldn't be in the slightest bit shocked, and fixing
it wouldn't take that much sophistication on the part of the user.)

A solution is the UUENCODE/UUDECODE program distributed with UNIX
(there are public domain versions) which encodes files in a very
conservative way (more or less 026 character subset, 40 chars/line.)
For example, I have a version of it running on our IBM mainframe and
it seems to work, particularly for cases as above (yes, I expand
tabs to every eight, perhaps that should be an option, but at least
it's all at the user level rather than a decision made by the SMTP daemon.)

Obviously with binary files there's not much you can do, but you
could pass one THROUGH an incompatible system with little risk of
problems using an encoding, hey, caveat usor.)

In re SMTP, I would vote conservative, change nothing unless you
have a good reason to (eg. ASCII->EBCDIC, there is an EBCDIC tab
character.) It should be easy enough to provide software to do
minor conversions once the the file has arrived (if it is intact,
expanding tabs for example discards information which seems to
violate some basic principle of design.)

	-Barry Shein, Boston University