Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!uunet!seismo!ut-sally!husc6!cmcl2!brl-adm!umd5!hans
From: hans@umd5.umd.edu (Hans Breitenlohner)
Newsgroups: comp.sys.atari.st
Subject: Re: UUENCODED files - corruption over BITNET
Message-ID: <1791@umd5.umd.edu>
Date: Wed, 15-Jul-87 16:29:22 EDT
Article-I.D.: umd5.1791
Posted: Wed Jul 15 16:29:22 1987
Date-Received: Fri, 17-Jul-87 07:29:40 EDT
References: <159@lithium.UUCP>
Reply-To: hans@umd5.umd.edu (Hans Breitenlohner)
Organization: University of Maryland, College Park
Lines: 32

In article <159@lithium.UUCP> andrew@lithium.UUCP (Andrew B Smith) writes:
>Could someone tell me the character changes that occure when a UUENCODED
>file is sent through an IBM host on BITNET (I think ~ is one).

UUENCODE uses the ASCII characters with values o40 to o137, or o41 to o140
in the case of some recent versions.  Unfortunately not all of these
have a (unique) representation in EBCDIC.  As a result some of these
get trashed when ASCII to EBCDIC translation is done on a host different
from the one doing EBCDIC to ASCII.  (I will assume that all hosts have
their act together sufficiently to give correct results when translating
both ways themselves, but even that is not always true).
The following characters are affected frequently:
  Left and right (square) brackets -- if you are lucky they will turn
                           into left and right braces.
  Caret sometimes turns into tilde.
  Backslash and accent grave have standard EBCDIC representation, but are
not on most IBM print chains / fonts / whatever they keep characters on
these days.  As a result, the corresponding translate tables may also not
be debugged.

All but the shortest UUENCODED files have several occurrences of all the
characters from o40 to o137 (or o41 to o140).  Look at them with your
favorite editor, and you may be able to figure out what substitutions
were made.  If the file is preceded by a copy of the ASCII alphabet
then this job is considerably simpler.

Finally, these hosts may also truncate lines with trailing blanks, and 
some UUDECODEs can not deal with truncated lines.  Again, your favorite
text editor should be able to help you out.

Sorry if some of this is more vague than what you had hoped for, but
such is the nature of the beast.