1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)lpd.8 8.3 (Berkeley) 4/19/94 29.\" $FreeBSD$ 30.\" 31.Dd April 15, 2021 32.Dt LPD 8 33.Os 34.Sh NAME 35.Nm lpd 36.Nd line printer spooler daemon 37.Sh SYNOPSIS 38.Nm 39.Op Fl cdlpsFW46 40.Op Ar port# 41.Sh DESCRIPTION 42The 43.Nm 44utility 45is the line printer daemon (spool area handler) and is normally invoked 46at boot time from the 47.Xr rc 8 48file. 49It makes a single pass through the 50.Xr printcap 5 51file to find out about the existing printers and 52prints any files left after a crash. 53It then uses the system calls 54.Xr listen 2 55and 56.Xr accept 2 57to receive requests to print files in the queue, 58transfer files to the spooling area, display the queue, 59or remove jobs from the queue. 60In each case, it forks a child to handle 61the request so the parent can continue to listen for more requests. 62.Pp 63Available options: 64.Bl -tag -width Ds 65.It Fl c 66By default, if some remote host has a connection error while trying to 67send a print request to 68.Nm 69on a local host, 70.Nm 71will only send error message to that remote host. 72The 73.Fl c 74flag causes 75.Nm 76to also log all of those connection errors via 77.Xr syslog 3 . 78.It Fl d 79Turn on 80.Dv SO_DEBUG 81on the Internet listening socket (see 82.Xr setsockopt 2 ) . 83.It Fl l 84The 85.Fl l 86flag causes 87.Nm 88to log valid requests received from the network. 89This can be useful 90for debugging purposes. 91.It Fl p 92The 93.Fl p 94flag is a synonym for the 95.Fl s 96flag. 97It is being deprecated, and may be removed in a 98future version of 99.Nm . 100.It Fl s 101The 102.Fl s 103(secure) flag causes 104.Nm 105not to open an Internet listening socket. 106This means that 107.Nm 108will not accept any connections from any remote 109hosts, although it will still accept print requests 110from all local users. 111.It Fl F 112By default, 113.Nm 114will daemonize into the background. 115The 116.Fl F 117flag causes 118.Nm 119to remain in the foreground. 120Logging is still performed with 121.Xr syslog 3 . 122.It Fl W 123By default, the 124.Nm 125daemon will only accept connections which originate 126from a reserved-port (<1024) on the remote host. 127The 128.Fl W 129flag causes 130.Nm 131to accept connections coming from any port. 132This is can be useful when you want to accept print jobs 133from certain implementations of lpr written for Windows. 134.It Fl 4 135Inet only. 136.It Fl 6 137Inet6 only. 138.It Fl 46 139Inet and inet6 (default). 140.It Ar "port#" 141The Internet port number used to rendezvous 142with other processes is normally obtained with 143.Xr getservbyname 3 144but can be changed with the 145.Ar port# 146argument. 147.El 148.Pp 149Access control is provided by two means. 150First, all requests must come from 151one of the machines listed in the file 152.Pa /etc/hosts.equiv 153or 154.Pa /etc/hosts.lpd . 155Second, if the 156.Li rs 157capability is specified in the 158.Xr printcap 5 159entry for the printer being accessed, 160.Em lpr 161requests will only be honored for those users with accounts on the 162machine with the printer. 163.Pp 164The file 165.Em minfree 166in each spool directory contains the number of kilobytes to leave free 167so that the line printer queue will not completely fill the disk. 168The 169.Em minfree 170file can be edited with your favorite text editor. 171.Pp 172The daemon begins processing files 173after it has successfully set the lock for exclusive 174access (described a bit later), 175and scans the spool directory 176for files beginning with 177.Em cf . 178Lines in each 179.Em cf 180file specify files to be printed or non-printing actions to be 181performed. 182Each such line begins with a key character 183to specify what to do with the remainder of the line. 184.Bl -tag -width Ds 185.It J 186Job Name. 187String to be used for the job name on the burst page. 188.It C 189Classification. 190String to be used for the classification line 191on the burst page. 192.It L 193Literal. 194The line contains identification info from 195the password file and causes the banner page to be printed. 196.It T 197Title. 198String to be used as the title for 199.Xr pr 1 . 200.It H 201Host Name. 202Name of the machine where 203.Xr lpr 1 204was invoked. 205.It P 206Person. 207Login name of the person who invoked 208.Xr lpr 1 . 209This is used to verify ownership by 210.Xr lprm 1 . 211.It M 212Send mail to the specified user when the current print job completes. 213.It f 214Formatted File. 215Name of a file to print which is already formatted. 216.It l 217Like ``f'' but passes control characters and does not make page breaks. 218.It p 219Name of a file to print using 220.Xr pr 1 221as a filter. 222.It t 223Troff File. 224The file contains 225.Xr troff 1 226output (cat phototypesetter commands). 227.It n 228Ditroff File. 229The file contains device independent troff 230output. 231.It r 232DVI File. 233The file contains 234.Tn Tex l 235output 236DVI format from Stanford. 237.It g 238Graph File. 239The file contains data produced by 240.Xr plot 3 . 241.It c 242Cifplot File. 243The file contains data produced by 244.Em cifplot . 245.It v 246The file contains a raster image. 247.It r 248The file contains text data with 249FORTRAN carriage control characters. 250.It \&1 251Troff Font R. 252Name of the font file to use instead of the default. 253.It \&2 254Troff Font I. 255Name of the font file to use instead of the default. 256.It \&3 257Troff Font B. 258Name of the font file to use instead of the default. 259.It \&4 260Troff Font S. 261Name of the font file to use instead of the default. 262.It W 263Width. 264Changes the page width (in characters) used by 265.Xr pr 1 266and the text filters. 267.It I 268Indent. 269The number of characters to indent the output by (in ASCII). 270.It U 271Unlink. 272Name of file to remove upon completion of printing. 273.It N 274File name. 275The name of the file which is being printed, or a blank 276for the standard input (when 277.Xr lpr 1 278is invoked in a pipeline). 279.It Z 280Locale. 281String to be used as the locale for 282.Xr pr 1 . 283.El 284.Pp 285If a file cannot be opened, a message will be logged via 286.Xr syslog 3 287using the 288.Em LOG_LPR 289facility. 290The 291.Nm 292utility will try up to 20 times 293to reopen a file it expects to be there, after which it will 294skip the file to be printed. 295.Pp 296The 297.Nm 298utility uses 299.Xr flock 2 300to provide exclusive access to the lock file and to prevent multiple 301daemons from becoming active simultaneously. 302If the daemon should be killed 303or die unexpectedly, the lock file need not be removed. 304The lock file is kept in a readable 305.Tn ASCII 306form 307and contains two lines. 308The first is the process id of the daemon and the second is the control 309file name of the current job being printed. 310The second line is updated to 311reflect the current status of 312.Nm 313for the programs 314.Xr lpq 1 315and 316.Xr lprm 1 . 317.Sh FILES 318.Bl -tag -width "/var/spool/*/minfree" -compact 319.It Pa /etc/printcap 320printer description file 321.It Pa /var/spool/* 322spool directories 323.It Pa /var/spool/*/minfree 324minimum free space to leave 325.It Pa /dev/lp* 326line printer devices 327.It Pa /var/run/printer 328socket for local requests 329.It Pa /etc/hosts.equiv 330lists machine names allowed printer access 331.It Pa /etc/hosts.lpd 332lists machine names allowed printer access, 333but not under same administrative control. 334.El 335.Sh SEE ALSO 336.Xr lpq 1 , 337.Xr lpr 1 , 338.Xr lprm 1 , 339.Xr setsockopt 2 , 340.Xr syslog 3 , 341.Xr hosts.lpd 5 , 342.Xr printcap 5 , 343.Xr chkprintcap 8 , 344.Xr lpc 8 , 345.Xr pac 8 346.Rs 347.\" 4.4BSD SMM:7 348.%A Ralph Campbell 349.%T "4.2 BSD Line Printer Spooler Manual" 350.Re 351.Sh HISTORY 352An 353.Nm 354daemon appeared in Version 6 AT&T UNIX. 355