netgroup_mkdb creates a
db(3) database for the specified file. If no file is specified, then
/etc/netgroup is used. This database is installed into
/var/db/netgroup.db. The file must be in the correct format (see
netgroup(5)).
The options are as follows:
-o database
Put the output databases in the named file.
The databases are used by the C library netgroup routines (see
getnetgrent(3)).
netgroup_mkdb exits zero on success, non-zero on failure.