UUCP Daemons

uucico

Selects the device used for the link, establishes the link to the remote computer, performs the required login sequence and permission checks, transfers data and execute files, logs results, and notifies the user by mail of transfer completions. It also starts uuxqt to execute any requested commands. When the local uucico daemon calls a remote computer, it "talks" to the uucico daemon on the remote computer during the session.

The uucico daemon is executed by the uucp, uuto, and uux programs, after all the required files have been created, to contact the remote computer. It is also executed by the uusched and Uutry programs.

uuxqt

Executes remote execution requests. This daemon searches the spool directory for execute files (always named X.file) that have been sent from a remote computer. When an X.file file is found, uuxqt opens it to get the list of data files that are required for the execution. It then checks to see if the required data files are available and accessible. If the files are present and can be accessed, uuxqt checks the Permissions file to verify that it has permission to execute the requested command. The uuxqt daemon is executed by the uudemon.hour shell script, which is started by cron.

uusched

Schedules the queued work in the spool directory. Before starting the uucico daemon, uusched randomizes the order in which remote computers are called. uusched is executed by a shell script called uudemon.hour, which is started by cron.

uugetty

This program is very similar to the getty program except that it permits a line (port) to be used in both directions. uugetty is assigned to a port in the /etc/inittab file if you want a port to be bi-directional. uugetty is described on the uugetty(1M) reference page.