This section describes three less-frequently modified files that impact the use of UUCP facilities.
The /etc/uucp/Devconfig file enables you to configure devices by service—uucp or cu. Devconfig entries define the STREAMS modules that are used for a particular device. They have the following format:
service=x device=y push=z[:z...]
x can be cu, uucico, or both services separated by a colon. y is the name of a network and must match an entry in the Devices file. z is replaced by the names of STREAMS modules in the order that they are to be pushed onto the Stream. Different modules and devices can be defined for cu and uucp services.
The following entries are for a STARLAN network and would most commonly be used in the file:
service=cu device=STARLAN push=ntty:tirdwr service=uucico device=STARLAN push=ntty:tirdwr
This example pushes ntty, then tirdwr.
The /etc/uucp/Limits file controls the maximum number of simultaneous uucicos, uuxqts, and uuscheds that are running in the uucp networking. In most situations, the default values are acceptable and no changes are needed. If you want to change them, however, use any text editor.
x can be uucico, uuxqt or uusched, and y is the limit that is permitted for that service. The fields can be in any order and in lowercase.
The following entries should most commonly be used in the Limits file:
service=uucico max=5 service=uuxqt max=5 service=uusched max=2
The other file that affects the use of communication facilities is the remote.unknown file. This file is a binary program that executes when a machine that is not found in any of the Systems files starts a conversation. This program logs the conversation attempt and drops the connection.
If you change the permissions of the remote.unknown file so that it cannot execute, your system accepts connections from any system.
This program executes when a machine that is not in any of the Systems starts a conversation. The program logs the conversation attempt but fails to make a connection. If you change the permissions of this file so that it cannot execute (chmod 000 remote.unknown), your system accepts any conversation requests. This is not a trivial change, and you should have good reasons for making it.