From owner-freebsd-questions Wed Nov 17 13:33:18 1999 Delivered-To: freebsd-questions@freebsd.org Received: from typhoon.mail.pipex.net (typhoon.mail.pipex.net [158.43.128.27]) by hub.freebsd.org (Postfix) with SMTP id C3C8B152D3 for ; Wed, 17 Nov 1999 13:33:12 -0800 (PST) (envelope-from mark@dogma.freebsd-uk.eu.org) Received: (qmail 21121 invoked from network); 17 Nov 1999 21:20:01 -0000 Received: from userbl16.uk.uudial.com (HELO marder-1.) (62.188.144.123) by smtp.dial.pipex.com with SMTP; 17 Nov 1999 21:20:01 -0000 Received: (from mark@localhost) by marder-1. (8.9.3/8.8.8) id VAA01027; Wed, 17 Nov 1999 21:08:13 GMT (envelope-from mark) Date: Wed, 17 Nov 1999 21:08:13 +0000 From: Mark Ovens To: James A Wilde Cc: freebsd-questions@freebsd.org Subject: Re: Corruption of file attachments passing late BSD relayers Message-ID: <19991117210813.B316@marder-1> References: <015a01bf30e8$1c8298d0$8c0aa8c0@hk.tbv.se> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0pre2i In-Reply-To: <015a01bf30e8$1c8298d0$8c0aa8c0@hk.tbv.se> Organization: Total lack of Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Wed, Nov 17, 1999 at 11:40:03AM +0100, James A Wilde wrote: > Digest: This message reports on the corruption of file attachments > in messages passing certain BSD UNIX mail exchangers. The > corruption affects messages sent using Microsoft Outlook and > Outlook Express mail clients. It may affect other clients also > The corrupted file attachments are about 30% larger than the > non-corrupted form. A small part of the increase appears to be the > insertion of CRLF at 76 character intervals. I have reported this > as a bug to FreeBSD.org but one of low priority. > This is not corruption. M$ proprietry files are binary so they are being uuencoded (which maps 3 bytes into 4 so that all bytes can be represented in printable chars). This explains the 30% increase in size and the CR/LF's as uuencode also splits the resultant file into fixed length lines. All you need is to uudecode(1) them. Netscape can do this and I'm sure that even M$ mail readers can as well; we have a mix of Unix and M$ (Outlook) systems at work and passing binary attachments poses no problems. ``man 5 uuencode'' for details of the algorithm used. As an aside, a customer mailed me a text file the other day, that was ~400K, as an attachment using M$ Exchange. By the time I got it it was >800K (this file would Zip down to <100K). Seems that Exchange embeds the fonts for RTF into the attachment that gets renamed winmail.dat. [snip] -- STATE-OF-THE-ART: Any computer you can't afford. OBSOLETE: Any computer you own. ________________________________________________________________ FreeBSD - The Power To Serve http://www.freebsd.org My Webpage http://ukug.uk.freebsd.org/~mark/ mailto:mark@ukug.uk.freebsd.org http://www.radan.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message