4.1cBSD/usr/man/man8/lpd.8

.TH LPD 8 "25 February 1983"
.UC 4
.ad
.SH NAME
lpd, lpdrestart \- line printer daemon, restart downed daemons at reboot time
.SH SYNOPSIS
.B /usr/lib/lpd printer
.br
.B /usr/lib/lpdrestart
.SH DESCRIPTION
.I Lpd
is the line printer daemon (spool area handler) invoked by
.IR lpr (1).
It uses the printer name argument to determine
the spooling directory, and other pertinent information.  The file
.I lock
in that directory is used to prevent multiple daemons from
becoming active simultaneously, and to store information
about the daemon process for
.IR lpq (1)
and
.IR lprm (1). 
After the daemon has succesfully set the lock, it scans the directory
for files beginning with 
.IR cf. 
Lines in each
.I cf
file specify files to be printed or non-printing actions to be
performed.  Each such line begins with a key character
to specify what to do with the remainder of the line.
.in +3
.IP J
Job Name.  String to be used for the job name on the burst page.
.IP C
Classification.  String to be used for the classification line
on the burst page.
.IP L
Literal.  The line contains identification info from
the password file and causes the banner page to be printed.
.IP T
Title.  String to be used as the title for
.IR pr(1).
.IP H
Host Name.  Name of the machine where
.I lpr
was invoked.
.IP P
Person.  Login name of the person who invoked
.I lpr.
This is used to verify ownership by
.I lprm.
.IP M
Send mail to the specified user when the current print job completes.
.IP f
Formatted File.  Name of a file to print which is already formatted.
.IP l
Like `f' but passes control characters and does not make page breaks.
.IP p
Name of a file to print using
.IR pr (1)
as a filter.
.IP t
Troff File.  The file contains
.IR troff (1)
output.
.IP c
Cifplot File. The file contains data produced by cifplot.
.IP v
Vplot File.  The file contains data produced by vplot.
.IP 1
Troff Font R. Name of the font file to use instead of the default.
.IP 2
Troff Font I. Name of the font file to use instead of the default.
.IP 3
Troff Font B. Name of the font file to use instead of the default.
.IP 4
Troff Font S. Name of the font file to use instead of the default.
.IP I
Indent.  The number of characters to indent the output by (in ascii).
.IP U
Unlink.  Name of file to remove upon completion of printing.
.IP N
File name.  The name of the file which is being printed, or a blank
for the standard input (when 
.I lpr
is invoked in a pipeline).
.in -5
.PP
Inability to open a file will result in a message being
printed in the log file (normally the console). 
.I lpd
will try up to 20 times
to reopen a file it expects to be there, after which it will
skip the file to be printed.
.PP
.I Lpd
uses
.IR flock (2)
to provide exclusive access to the lock file and to prevent multiple
deamons from becoming active simultaneously. If the daemon should be killed
or die unexpectedly, the lock file need not be removed.
The lock file is maintained in a character format and contains two lines.
The first is the process id of the daemon and the second is the control
file name of the current job being printed.  The second line is updated to
reflect the current status of
.I lpd
for the programs
.IR lpq (1)
and
.IR lprm (1).
.PP
.I lpdrestart
is normally placed in the
.IR rc (8)
file to automatically restart spooling daemons after a crash.
It makes a single pass through the
.IR printcap (5)
file to find out about the existing printers.
.SH FILES
.nf
.ta \w'/etc/printcap           'u
/etc/printcap	printer description file
/usr/spool/*	spool directories
/dev/lp*	line printer devices
.fi
.SH "SEE ALSO"
lpr(1),
lpq(1),
lprm(1),
printcap(5)