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LPD(8)			     System Manager's Manual			  LPD(8)

NAME
     lpd -- line printer spooler daemon

SYNOPSIS
     lpd [-cdlpsW46] [port#]

DESCRIPTION
     The lpd utility is the line printer daemon (spool area handler) and is nor-
     mally  invoked  at  boot  time from the rc(8) file.  It makes a single pass
     through the printcap(5) file to find out about the  existing  printers  and
     prints  any  files  left after a crash.  It then uses the system calls lis-
     ten(2) and accept(2) to receive requests  to  print  files  in  the  queue,
     transfer files to the spooling area, display the queue, or remove jobs from
     the  queue.   In  each  case, it forks a child to handle the request so the
     parent can continue to listen for more requests.

     Available options:

     -c      By default, if some remote host has a connection error while trying
	     to send a print request to lpd on a local host, lpd will only  send
	     error  message to that remote host.  The -c flag causes lpd to also
	     log all of those connection errors via syslog(3).

     -d      Turn on SO_DEBUG on the Internet  listening  socket  (see	setsock-
	     opt(2)).

     -l      The -l flag causes lpd to log valid requests received from the net-
	     work.  This can be useful for debugging purposes.

     -p      The -p flag is a synonym for the -s flag.	It is being depreciated,
	     and may be removed in a future version of lpd.

     -s      The  -s  (secure) flag causes lpd not to open an Internet listening
	     socket.  This means that lpd will not accept any  connections  from
	     any remote hosts, although it will still accept print requests from
	     all local users.

     -W      By default, the lpd daemon will only accept connections which orig-
	     inate from a reserved-port (<1024) on the remote host.  The -W flag
	     causes lpd to accept connections coming from any port.  This is can
	     be useful when you want to accept print jobs from certain implemen-
	     tations of lpr written for Windows.

     -4      Inet only.

     -6      Inet6 only.

     -46     Inet and inet6 (default).

     port#   The Internet port number used to rendezvous with other processes is
	     normally obtained with getservbyname(3) but can be changed with the
	     port# argument.

     Access  control  is  provided  by two means.  First, all requests must come
     from  one	of  the  machines  listed  in  the  file   /etc/hosts.equiv   or
     /etc/hosts.lpd.   Second,	if  the rs capability is specified in the print-
     cap(5) entry for the printer being accessed, lpr requests will only be hon-
     ored for those users with accounts on the machine with the printer.

     The file minfree in each spool directory contains the number of disk blocks
     to leave free so that the line printer  queue  won't  completely  fill  the
     disk.  The minfree file can be edited with your favorite text editor.

     The  daemon  begins processing files after it has successfully set the lock
     for exclusive access (described a bit later), and scans the spool directory
     for files beginning with cf.  Lines in each 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.

     J	     Job Name.	String to be used for the job name on the burst page.

     C	     Classification.  String to be used for the classification	line  on
	     the burst page.

     L	     Literal.	The  line contains identification info from the password
	     file and causes the banner page to be printed.

     T	     Title.  String to be used as the title for pr(1).

     H	     Host Name.  Name of the machine where lpr was invoked.

     P	     Person.  Login name of the person who invoked lpr.  This is used to
	     verify ownership by lprm.

     M	     Send mail to the specified user when the  current	print  job  com-
	     pletes.

     f	     Formatted	File.	Name of a file to print which is already format-
	     ted.

     l	     Like ``f'' but passes control characters and  does  not  make  page
	     breaks.

     p	     Name of a file to print using pr(1) as a filter.

     t	     Troff File.  The file contains troff(1) output (cat phototypesetter
	     commands).

     n	     Ditroff File.  The file contains device independent troff output.

     r	     DVI  File.   The  file contains Tex l output DVI format from Stand-
	     ford.

     g	     Graph File.  The file contains data produced by plot(3).

     c	     Cifplot File.  The file contains data produced by cifplot.

     v	     The file contains a raster image.

     r	     The file contains text data with FORTRAN carriage	control  charac-
	     ters.

     1	     Troff Font R. Name of the font file to use instead of the default.

     2	     Troff Font I. Name of the font file to use instead of the default.

     3	     Troff Font B. Name of the font file to use instead of the default.

     4	     Troff Font S. Name of the font file to use instead of the default.

     W	     Width.   Changes  the  page width (in characters) used by pr(1) and
	     the text filters.

     I	     Indent.  The number of characters	to  indent  the  output  by  (in
	     ASCII).

     U	     Unlink.  Name of file to remove upon completion of printing.

     N	     File name.  The name of the file which is being printed, or a blank
	     for the standard input (when lpr is invoked in a pipeline).

     Z	     Locale.  String to be used as the locale for pr(1).

     If  a  file  cannot be opened, a message will be logged via syslog(3) using
     the LOG_LPR facility.  The lpd utility 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.

     The lpd utility uses flock(2) to provide exclusive access to the lock  file
     and  to  prevent  multiple daemons from becoming active simultaneously.  If
     the daemon should be killed or die unexpectedly, the lock file need not  be
     removed.	The  lock file is kept in a readable ASCII form 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 up-
     dated  to	reflect  the  current  status of lpd for the programs lpq(1) and
     lprm(1).

FILES
     /etc/printcap	   printer description file
     /var/spool/*	   spool directories
     /var/spool/*/minfree  minimum free space to leave
     /dev/lp*		   line printer devices
     /var/run/printer	   socket for local requests
     /etc/hosts.equiv	   lists machine names allowed printer access
     /etc/hosts.lpd	   lists machine names allowed printer access,	but  not
			   under same administrative control.

SEE ALSO
     lpq(1),  lpr(1),  lprm(1),  setsockopt(2),  syslog(3), hosts.lpd(5), print-
     cap(5), chkprintcap(8), lpc(8), pac(8)

     4.2 BSD Line Printer Spooler Manual.

HISTORY
     An lpd daemon appeared in Version 6 AT&T UNIX.

FreeBSD 4.7			  June 06, 2001 			  LPD(8)

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