74 Mail some non-standard environment variable set so he couldn’t use Emacs or vi or any other screen editor so he couldn’t see there was an extra blank line that Unix would rather choke dead on than skip over. That’s why. From: MAILER-DAEMON@berkeley.edu The problem with sendmail is that the sendmail configuration file is a rule-based expert system, but the world of e-mail is not logical, and sendmail configuration editors are not experts. —David Waitzman, BBN Beyond blowing established mail delivery protocols, Unix has invented newer, more up-to-date methods for ensuring that mail doesn’t get to its intended destination, such as mail forwarding. Suppose that you have changed your home residence and want your mail forwarded automatically by the post office. The rational method is the method used now: you send a message to your local postmaster, who main- tains a centralized database. When the postmaster receives mail for you, he slaps the new address on it and sends it on its way to its new home. There’s another, less robust method for rerouting mail: put a message near your mailbox indicating your new address. When your mailman sees the message, he doesn’t put your mail in your mailbox. Instead, he slaps the new address on it and takes it back to the post office. Every time. The flaws in this approach are obvious. For one, there’s lots of extra over- head. But, more importantly, your mailman may not always see the mes- sage—maybe it’s raining, maybe someone’s trash cans are in front of it, maybe he’s in a rush. When this happens, he misdelivers your mail into your old mailbox, and you never see it again unless you drive back to check or a neighbor checks for you. Now, we’re not inventing this stupider method: Unix did. They call that note near your mailbox a .forward file. And it frequently happens, espe- cially in these distributed days in which we live, that the mailer misses the forwarding note and dumps your mail where you don’t want it. 3“Ed is the standard Unix editor.” —Unix documentation (circa 1994).
From: MAILER-DAEMON@berkeley.edu 75 Date: Thu, 6 Oct 88 22:50:53 EDT From: Alan Bawden alan@ai.mit.edu To: SUN-BUGS Cc: UNIX-HATERS Subject: I have mail? Whenever log into a Sun, I am told that I have mail. I don’t want to receive mail on a Unix, I want my mail to be forwarded to “Alan@AI.” Now as near as I can tell, I don’t have a mailbox in my home directory on the Suns, but perhaps Unix keeps mailboxes else- where? If I send a test message to “alan@wheaties” it correctly finds its way to AI, just as the .forward file in my home directory says to do. I also have the mail-address field in my inquir entry set to “Alan@AI.” Nevertheless, whenever I log into a Sun, it tells me that I have mail. (I don’t have a personal entry in the aliases file, do I need one of those in addition to the .forward file and the inquir entry?) So could someone either: A. Tell me that I should just ignore the “You have mail” message, because in fact I don't have any mail accumulating in some dark corner of the file system, or B. Find that mail and forward it to me, and fix it so that this never happens again. Thanks. The next day, Alan answered his own query: Date: Fri, 7 Oct 88 14:44 EDT From: Alan Bawden alan@ai.ai.mit.edu To: UNIX-HATERS Subject: I have mail? Date: Thu, 6 Oct 88 22:50:53 EDT From: Alan Bawden alan@ai.mit.edu (I don’t have a personal entry in the aliases file, do I need one of those in addition to the .forward file and the inquir entry?) Apparently the answer to this is “yes.” If the file server that contains your home directory is down, the mailer can’t find your .forward file,
Previous Page Next Page