NcFTPd general.cf file configuration
Don't forget to restart NcFTPd after modifying the general.cf file.
If you have some sort of special requirement to authenticate users that isn't served by the standard methods, you can have an external process authenticate user logins. Setting the ncftpd_authd option will require NcFTPd to send messages to this process to do the logins.
Odds are very slim you will need this option. If you do, see the additional documentation for it.