xref: /freebsd/share/doc/smm/07.lpd/1.t (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
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Overview

The line printer system supports:

\(bu 3
multiple printers,
\(bu 3
multiple spooling queues,
\(bu 3
both local and remote printers, and
\(bu 3
printers attached via serial lines that require line initialization such as the baud rate.

Raster output devices such as a Varian or Versatec, and laser printers such as an Imagen, are also supported by the line printer system.

The line printer system consists mainly of the following files and commands:

/etc/printcap printer configuration and capability data base
/usr/lib/lpd line printer daemon, does all the real work
/usr/ucb/lpr program to enter a job in a printer queue
/usr/ucb/lpq spooling queue examination program
/usr/ucb/lprm program to delete jobs from a queue
/etc/lpc program to administer printers and spooling queues
/dev/printer socket on which lpd listens
The file /etc/printcap is a master data base describing line printers directly attached to a machine and, also, printers accessible across a network. The manual page entry printcap (5) provides the authoritative definition of the format of this data base, as well as specifying default values for important items such as the directory in which spooling is performed. This document introduces some of the information that may be placed printcap .