Class via Database-Map Lookups

Beginning with V8.12, you can declare class values by specifying and using database maps. Database maps are described in Chapter 23 on page 878. In its simplest form, such a declaration looks like this:

FXkey@ type:detail
F{Name}key@ type:detail

Each such declaration begins with the F configuration command, which is immediately followed (with no intervening space) by the name of the class that will be filled with values. The first line shows the single-character name form (the X) and the second line shows the multicharacter name form (the {Name}).

The name of the class is immediately followed by the key to look up in the database map. Note that you must be very careful to specify a key that actually exists. If the key is not found in the database map, sendmail silently ignores the error.

The key is immediately followed by a literal @ character, which in turn is immediately followed by the type of the database map. A db-type database map, for example, could have a type of either hash or btree. An ldap-type database map, for example, would have a type of ldap. (We discuss ldap in detail in the next section.) A complete list of types can be found in the leftmost column of Table 23-2 on page 883.

The type is immediately followed by a colon and then by the detail. The nature of the detail varies depending on what you want this command to do. To illustrate, consider the following addition to an mc configuration file:

LOCAL_CONFIG FwCWhosts@hash:/etc/mail/access ...

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