Sendmail, 3rd Edition

Name

FEATURE(genericstable)

Synopsis

The User Database (userdb) allows recipient addresses to be changed so that they can be delivered to new hosts. For example, [e-mail] can be transformed with the User Database into [e-mail]. The genericstable provides the same type of transformation on the sender’s address.

To begin, create a file of the form:

user                [e-mail]
[e-mail]    [e-mail]

In it, each line begins with the old address, either the user part alone, or the full address. On the right is the new address for that sender. One example of a use for this table might be to make the user news always appear as though it was from the news machine:

news            [e-mail]
[e-mail] [e-mail]

Note that the bare user part (news in the first line) is looked up only if sendmail considers it to be in the local domain. If a domain is listed (as in the second line in the preceding example) that entry is looked up only if it is in a special class defined with the GENERICS_DOMAIN mc macro (Section 4.8.1). If you want subdomains to also match, you must declare the generics_entire_domain feature (FEATURE(generics_entire_domain)). Ways to list domains in that special class are outlined later in this chapter.

The makemap(1) program (Section 5.5) is then used to convert this file into a database:

makemap hash db_file <  text_file

Here, db_file is the name you give to the created database, and text_file is the name of the source text file.

Note ...