Networking programs

BNU consists of programs and support files. BNU programs include user programs, administrative programs, and daemons. These three types of BNU programs are described here.

BNU support files are described in detail in ``Networking support files''.

User programs

The Basic Networking Utilities user programs are:

cu

Calls another UNIX system, a terminal, or possibly a non-UNIX system and manages an interactive conversation with possible transfers of files. See cu(1bnu) for more information.

ct

Dials the telephone number of a modem that is attached to a terminal and spawns a login process to that terminal. See ct(1bnu) for more information.

uucp

Copies files from a local machine to a destination either on the same machine or on a remote UNIX machine. uucp can also copy files from a remote computer to another remote computer, copy files from one location to another on a given remote computer, and copy files from a remote computer to a local computer. Some remote copies will be restricted by the administrator of the remote machine. See uucp(1bnu) for more information.

uuto

Uses the uucp facility to send files to the public directory PUBDIR on another system. See uuto(1bnu) for more information.

uupick

Accepts or rejects files transmitted to a user. Specifically, uupick searches PUBDIR for files destined for the user. uupick is described on uuto(1bnu).

uux

Gathers files from various systems, executes a command on a named system, and then sends the output to a file on another named system. See uux(1bnu) for more information.

uustat

Displays the status of, or cancels, previously specified uucp commands; provides remote system performance information; and provides remote status of uucp connections to other systems. See uustat(1bnu) for more information.

uulog

Queries log files of uucp and uuxqt transactions. uuxqt is described in ``Networking daemons''. uulog is described on uucp(1bnu).

uuglist

Prints the list of service grades available on a system for use with the -g option of uucp and uux. See uuglist(1bnu) for more information.

uuname

Lists the names of systems known to uucp. uuname is described on uucp(1bnu).

uuencode

Converts a binary file into an ASCII file that can be transmitted using mail(1). See uuencode(1bnu) for more information.

uudecode

Reads an encoded file, strips off any leading and trailing lines added by mailer programs, and re-creates the original binary data. See uuencode(1bnu) for more information.

Administrative programs

The Basic Networking Utilities include the following three administrative programs:

uucheck

Checks for the presence of the uucp system-required files and directories. uucheck also checks the /etc/uucp/Permissions file for errors. See uucheck(1Mbnu) for more information.

uucleanup

Scans the spool directories for old files and removes them. The default values for file aging can be changed by command line options. An option also exists to restrict uucleanup's action to the system spool directory. See uucleanup(1Mbnu) for more information.

Uutry

Uutry is a shell that invokes uucico when calling a remote site. Debugging is initially turned on and the debugging output is put in a file. See Uutry(1Mbnu) for more information.

Since uucp owns the BNU and spooled data files, the uucp login ID should be used only for BNU administration. The home directory for the uucp login is /usr/lib/uucp. Another BNU login ID, nuucp, is used by remote computers to access the local machine. Calls to nuucp are answered by uucico.

Networking daemons

The BNU software includes three daemons. A daemon is a standing server or a routine that runs as a background process and performs system-wide public functions. The BNU daemons handle both file transfers and command execution. They may be invoked from the shell.

uucico

Checks permissions, transfers files (if requested), logs results, and notifies the user (by mail) of transfer completion. When the local uucico daemon calls a remote computer, it invokes the dials routine (see dials(3N)), which then obtains authenticated connections from the connection server. uucico 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 uusched and Uutry. See uucico(1Mbnu) for more information.

uuxqt

Executes remote execution requests. uuxqt searches the spool directory for execute files (always named X.file) that have been sent from a remote computer. When an execute file is found, uuxqt opens it to get the list of data files 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(4bnu) file to verify that it has permission to execute the requested command. uuxqt is executed by the uudemon.hour shell script, which is started by cron. See uuxqt(1Mbnu) for more information.

uusched

Schedules the queued work in the spool directory. Before starting uucico, uusched randomizes the order in which remote computers will be called. uusched is executed by the shell script uudemon.hour, which is started by cron. See uusched(1Mbnu) for more information.