Internal Mailing Lists
An internal mailing list is simply an entry in the aliases file that has more than one recipient listed on the right-hand side. Consider, for example, the following aliases file entries:
admin: bob,jim,phil bob: \bob,/u/bob/admin/maillog
Here, the name admin
is actually the name of a
mailing list because it expands to more than one recipient.
Similarly, the name bob
is a mailing list because
it expands to two recipients. Because bob
is also
included in the admin
list, mail sent to that
mailing list will be alias-expanded by sendmail
to produce the following list of recipients:
jim, phil, \bob, /u/bob/admin/maillog
This causes the mail message to be delivered to the local users
jim
and phil
in the normal way.
That is, each undergoes additional alias processing, and the
~/.forward file of each is examined to see
whether either should be forwarded. The recipient
\bob
, on the other hand, is delivered without any
further aliasing because of the leading backslash. Finally, the
message is appended to the file
/u/bob/admin/maillog.
Internal mailing lists can become very complex as they strive to support the needs of large institutions. Examine the following simple, but revealing, example:
research: user1, user2 applications: user3, user4 admin: user5, user6 advertising: user7, user8 engineering: research, applications frontoffice: admin, advertising everyone: engineering, frontoffice
Only the first four aliases expand to real usernames. The last three form mailing lists ...
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