The /usr/lib/uucp/remote.unknown file contains a shell procedure. It is executed by the uucp program when a remote computer that is not listed in the local /usr/lib/uucp/Systems file attempts to communicate with that local system. The uucp program does not permit the unknown remote system to connect with the local system. Instead, the remote.unknown shell procedure appends an entry to the file /usr/spool/uucp/.Admin/Foreign.
Modify the remote.unknown file to fit the needs of your site. For example, to allow unknown systems to contact your system, remove the execute permissions for the remote.unknown file. You can also modify the shell script to send mail to the uucp administrator or to recognize certain systems and reject others.
Only someone with superuser authority can edit the remote.unknown file, which is owned by the uucp program login ID.