82 Mail Date: Tue, 4 Aug 92 16:07:47 HKT From: “Olin G. Shivers” shivers@csd.hku.hk To: UNIX-HATERS Subject: Need your help. Anybody who thinks that uuencode protects a mail message is living in a pipe dream. Uuencode doesn’t help. The idiot program uses ASCII spaces in its encoding. Strings of nuls map to strings of blanks. Many Unix mailers thoughtfully strip trailing blanks from lines of mail. This nukes your carefully–encoded data. Well, it’s Unix, what did you expect? Of course you can grovel over the data, find the lines that aren’t the right length, and re-pad with blanks—that will (almost certainly?) fix it up. What else is your time for anyway, besides cleaning up after the interactions of multiple brain-damaged Unix so-called “utilities?” Just try and find a goddamn spec for uuencoded data sometime. In the man page? Hah. No way. Go read the source—that’s the “spec.” I particularly admire the way uuencode insists on creating a file for you, instead of working as a stdio filter. Instead of piping into tar, which knows about creating files, and file permissions, and directo- ries, and so forth, we build a half-baked equivalent functionality directly into uuencode so it’ll be there whether you want it or not. And I really, really like the way uuencode by default makes files that are world writable. Maybe it’s Unix fighting back, but this precise bug hit one of the editors of this book after editing in this message in April 1993. Someone mailed him a uuencoded PostScript version of a conference paper, and fully 12 lines had to be handpatched to put back trailing blanks before uudecode repro- duced the original file. Error Messages The Unix mail system knows that it isn’t perfect, and it is willing to tell you so. But it doesn’t always do so in an intuitive way. Here’s a short listing of the error messages that people often witness: 550 chiarell... User unknown: Not a typewriter 550 bogus@ASC.SLB.COM... User unknown: Address already in use
From: MAILER-DAEMON@berkeley.edu 83 550 zhang@uni-dortmund.de... User unknown: Not a bicycle 553 abingdon I refuse to talk to myself 554 “| /usr/new/lib/mh/slocal -user $USER”... unknown mailer error 1 554 “| filter -v”... unknown mailer error 1 554 Too many recipients for no message body “Not a typewriter” is sendmail’s most legion error message. We figure that the error message “not a bicycle” is probably some system administrator’s attempt at humor. The message “Too many recipients for no message body” is sendmail’s attempt at Big Brotherhood. It thinks it knows better than the proletariat masses, and it won’t send a message with just a subject line. The conclusion is obvious: you are lucky to get mail at all or to have mes- sages you send get delivered. Unix zealots who think that mail systems are complex and hard to get right are mistaken. Mail used to work, and work highly reliably. Nothing was wrong with mail systems until Unix came along and broke things in the name of “progress.” Date: Tue, 9 Apr 91 22:34:19 -0700 From: Alan Borning borning@cs.washington.edu To: UNIX-HATERS Subject: the vacation program So I went to a conference the week before last and decided to try being a Unix weenie, and set up a “vacation” message. I should have known better. The vacation program has a typical Unix interface (involving creat- ing a .forward file with an obscure incantation in it, a .vacation.msg file with a message in it, etc.) There is also some -l initialization option, which I couldn’t get to work, which is supposed to keep the vacation replies down to one per week per sender. I decided to test it by sending myself a message, thinking that surely they would have allowed for this and prevented an infinite sending of vacation mes- sages. A test message, a quick peek at the mail box, bingo, 59 mes- sages already. Well. It must be working.
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