To solve this problem, first ensure that the "localhost" entry is present in the "/etc/hosts" file.
The "biff" notification is invoked by the sender's mailer (in this case, "/bin/mail"), which calls the "gethostbyname()" system call with "localhost" as its argument. This connects to the receiver's comsat server, which in turn alerts the receiver.
If your "/etc/hosts" file does not have the "localhost" entry, the "bin/mail" program will not try to call the receiver's comsat program.
Unfortunately, the "localhost" entry is not included in the distributed "/etc/hosts" file.
To make it possible for "/bin/mail" to connect to comsat, add the "localhost" name in the local loop back entry line in the "/etc/hosts" file:
127.0.0.1 localhost loop lo loo
This doesn't work under any shell without the "localhost" name in the "/etc/hosts" file.
Article Change History:
23 Aug 1994 - Reviewed and updated.
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