<para>
When using an external authentication system such as Ident or GSSAPI,
the name of the operating system user that initiated the connection
- might not be the same as the database user that is to be connect as.
+ might not be the same as the database user (role) that is to be used.
In this case, a user name map can be applied to map the operating system
user name to a database user. To use user name mapping, specify
<literal>map</literal>=<replaceable>map-name</replaceable>