/etc/printcap"> /etc/lpd.conf"> /etc/lpd.perms"> ]> The Printing Cookbook Updated 5 Sept 2003 Patrick A Powell
papowell@lprng.com AStArt Technologies 6741 Convoy Court, San Diego, CA 92111 Phone 858-874-6543 Fax 858-751-2435
2001-2003 Patrick Powell $Id: Cookbook.sgml,v 1.3 2003/09/06 02:07:15 papowell Exp $ This is a set of Preface A good cookbook will provide the reader not only with a set of recipes that sound delicious but also with a set of instructions that will allow novices to experts to prepare them. Of course, there are cookbooks for novices, cookbooks for experts, and then the gastronmic encyclopedias. These The various test files, scripts and examples in this document are also in the &LPRng; distribution in the /LPRng-xxx/UTILS directory. Enjoy! Bon Appetite! Acknowledgements I would like to thank all of the &LPRng; users who so relentlessly tried an incredible number of permutations and combinations printers, software, and networks, and whose requests for just one more feature led to the development of the &LPRng; software. Conventions Many examples will show commands run by ordinary or privleged users. The prompt character will indicate the user: User Prompt Normal user host {20} % su root host {2} # Recipes and major examples will be show as:
<application/lpq/ status h110: {64} % lpq Printer: lp@h110 Queue: no printable jobs in queue Status: job 'cfA711h110.private' removed at 17:11:43.919 Filter_status: done at 17:11:43.823
Smaller sets of code or commands will be shown as: Queue: no printable jobs in queue Disclaimer THIS DOCUMENTATION AND THE DESCRIBED SOFTWARE AND PROCEDURES IS PROVIDED BY THE AUTHORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. Introduction - The Basics and Variations
Print Spooler Architecture
The &LPRng; print spooling system has the components shown in . A program generates output and pipes it to the &lpr; application or the &lpr; application is used to print a file. The &lpr; application connects to the &lpd; print server over a network connection and then transfers the print job data and print options. The &lpd; server will store the job information in a spool directory and when the output device is available will transfer the job to the printing device. Since the print job may not be in the appropriate format for the ouput device a , transferred directly to a TCP/IP network port.
Configuration Files
As shown in , the &LPRng; print spooler uses the &printcap;, &conf;, and &perms;, files to get its operational parameters. The the &printcap; file defines a set of spool queues, each of which holds print jobs. A print job if transfered to the print server as a a
Printcap # Common configuration information .common:sd=/var/spool/lpd/%P :sh:mx=0:force_localhost # forward to remote spooler lp:cm=Default Printer :tc=.common :lp=raw@10.0.0.1 # legacy - :rp=raw:rm=10.0.0.1 # lp0 - open a device lp0|aliasforlp0:cm=Parallel Port Printer:\ :tc=.common:lp=/dev/lpt0: # lp1 - open a network connection lp1:tc=.common:lp=10.0.0.14%9100 # lp2 - run a program lp2:tc=.common:lp=|/usr/local/bin/smbprint
The &printcap; file format is very simple in appearance but complex in information. By convention, lines starting with The Simple Spooling This section covers the basic facilities that you will probably encounter when trying to set up a print queue. We will start with a basic print queue and then run through the setup steps.
Basic Printcap Entry # Common configuration information .common:sd=/var/spool/lpd/%P :sh:mx=0:force_localhost lp:cm=Default Printer, Forward to remote :tc=.common :lp=raw@10.0.0.1 # lp0 - open a device lp0:cm=Parallel Port Printer :tc=.common:lp=/dev/lpt0:
Setting Up The Print Queues
Run checkpc h110: {1} % checkpc Warning - bad directory - /var/spool/lpd/lp Warning - Printer_DYN 'lp' spool dir '/var/spool/lpd/lp' needs fixing Warning - bad directory - /var/spool/lpd/lp0 Warning - Printer_DYN 'lp0' spool dir '/var/spool/lpd/lp0' needs fixing h110: {2} % su Password: h110# checkpc -f Warning - changing ownership '/var/spool/lpd/lp' to 1/1 Warning - changing ownership '/var/spool/lpd/lp' to 1/1 Warning - changing ownership '/var/spool/lpd/lp0' to 1/1 Warning - changing ownership '/var/spool/lpd/lp0' to 1/1 h110# exit h110: {3} % checkpc h110: {4} % checkpc
First, you run
Check for Running Server h110: {5} % lpc lpd Printer 'lp@localhost' - cannot open connection - Connection refused Make sure the remote host supports the LPD protocol h110: {6} % su Password: h110# lpd h110# lpc lpd lpd server pid 6418 on h110.private h110# exit exit h110: {7} % lpc lpd lpd server pid 6418 on h110.private
Next, you make sure the &lpd; server is running, and if it is not, then you restart it.
Run &lpq; h110: {373} % lpq -a Printer: lp@h110 Queue: no printable jobs in queue Printer: lp0@h110 Queue: no printable jobs in queue
You now make sure that you can get the print queue status.
Run &lpc; h110: {374} % lpc stop lp lp0 Printer: lp@h110 lp@h110.private: stopped Printer: lp0@h110 lp0@h110.private: stopped h110: {375} % lpq -a Printer: lp@h110 (printing disabled) Queue: no printable jobs in queue Printer: lp0@h110 (printing disabled) Queue: no printable jobs in queue
Use &lpc; to disable printing.
Run &lpr; h110: {376} % echo hi >/tmp/hi h110: {377} % lpr /tmp/hi h110: {378} % lpq Printer: lp@h110 (printing disabled) Queue: 1 printable job Server: no server active Rank Owner/ID Class Job Files Size Time 1 papowell@h110+445 A 445 /tmp/hi 3 17:40:51 h110: {379} % lpr -Plp0 /tmp/hi h110: {380} % lpq -Plp0 Printer: lp0@h110 (printing disabled) Queue: 1 printable job Server: no server active Rank Owner/ID Class Job Files Size Time 1 papowell@h110+449 A 449 /tmp/hi 3 17:41:05
Now try spooling a job.
Run &lprm; h110: {381} % lprm Printer lp@h110: checking perms 'papowell@h110+445' dequeued 'papowell@h110+445' h110: {382} % lprm -Plp0 Printer lp0@h110: checking perms 'papowell@h110+449' dequeued 'papowell@h110+449'
Now try removing a job.
Enable Printing h110: {383} % lpc enable lp lp0 Printer: lp@h110 lp@h110.private: enabled Printer: lp0@h110 lp0@h110.private: enabled
Finally, enable printing. Diagnostics for Spooling Problems
Using &lpr; -V h110: {388} % lpr -V /tmp/hi LPRng-3.7.10, Copyright 1988-2001 Patrick Powell, <papowell@lprng.com> sending job 'papowell@h110+29' to lp@localhost connecting to 'localhost', attempt 1 connected to 'localhost' requesting printer lp@localhost sending control file 'cfA029h110.private' to lp@localhost completed sending 'cfA029h110.private' to lp@localhost sending data file 'dfA029h110.private' to lp@localhost completed sending 'dfA029h110.private' to lp@localhost done job 'papowell@h110+29' transfer to lp@localhost
The first line of defense is to see what is happening when you try to spool a job. The
The &lpr; Options h110: {389} % lpr -= lpr: Illegal option '=' Usage: lpr [-Pprinter[@host]] [-A] [-B] [-Cclass] [-Fformat] [-G] [-Jinfo] [-(K|#)copies] [-Q] [-Raccountname] [-Ttitle] [-Uuser[@host]] [-V] [-Zoptions] [-b] [-m mailaddr] [-h] [-i indent] [-l] [-w width ] [-r] [-Ddebugopt ] [--] [ filenames ... ] -A - use authentication specified by AUTH environment variable -B - filter files and reduce job to single file before sending -C class - job class -D debugopt - debugging flags -F format - job format -b,-l - binary or literal format c,d,f,g,l,m,p,t,v are also format options -G - filter individual job files before sending -J info - banner and job information -K copies, -# copies - number of copies -P printer[@host] - printer on host -Q - put 'queuename' in control file -Raccntname - accounting information -T title - title for 'pr' (-p) formatting -U username - override user name (restricted) -V - Verbose information during spooling -X path - user specified filter for job files -Y - connect and send to TCP/IP port (direct mode) -Z options - options to pass to filter -h - no header or banner page -i indent - indentation -k - do not use tempfile when sending to server -m mailaddr - mail final status to mailaddr -r - remove files after spooling -w width - width to use -- - end of options, files follow filename '-' reads from STDIN PRINTER, LPDEST, NPRINTER, NGPRINTER environment variables set default printer. LPRng-3.7.10, Copyright 1988-2001 Patrick Powell, <papowell@lprng.com>
Use the
Debug Options h110: {392} % lpr -D= debug usage: -D [ num | flag=num | flag=str | flag | flag@ | flag+N ]* flags recognized: network[+N,@], database[+N,@], lpr[+N,@], lpc[+N,@], lprm[+N,@], lpq[+N,@], log[+N,@], test=num
The
The &lpr; -D1 Output h110: {395} % lpr -D1 /tmp/hi >&/tmp/x 2001-10-18-05:29:05 [8052] Initialize: /dev/null fd 3 2001-10-18-05:29:05 [8052] initsetproctitle: using builtin 2001-10-18-05:29:05 [8052] lpr Setup_uid: OriginalEUID 0, OriginalRUID 1001 2001-10-18-05:29:05 [8052] lpr Setup_uid: OriginalEGID 1001, OriginalRGID 1001 2001-10-18-05:29:05.761 [8052] lpr Setup_configuration: starting, Allow_getenv 0 2001-10-18-05:29:05.761 [8052] lpr Setup_configuration: Configuration file '/etc/lpd.conf' 2001-10-18-05:29:05.761 [8052] lpr Setup_configuration: Require_configfiles_DYN '1' 2001-10-18-05:29:05.761 [8052] lpr Get_config: required '1', '/etc/lpd.conf' 2001-10-18-05:29:05.762 h110 [8052] lpr Get_local_host: ShortHost_FQDN=h110, FQDNHost_FQDN=h110.private 2001-10-18-05:29:05.763 h110 [8052] lpr Is_server 0, DaemonUID 1, DaemonGID 1, UID 0, EUID 0, GID 1001, EGID 1001 2001-10-18-05:29:05.763 h110 [8052] lpr Setup_configuration: Host 'h110.private', ShortHost 'h110', user 'papowell' ...
The &lpr;
Using &lpr; -Dnetwork h110: {400} % lpr -Dnetwork /tmp/hi lp: getconnection: START host localhost, timeout 10, connection_type 1 lp: getconnection: fqdn found localhost.my.domain, h_addr_list count 1 lp: Link_dest_port_num: port 515 = 515 lp: getconnection: AGAIN port 808, min 512, max 1023, count 0, connects 0 lp: Link_dest_port_num: port 515 = 515 lp: getconnection: sock 3, src ip 127.0.0.1, port 808 lp: getconnection: dest ip 127.0.0.1, port 515 lp: getconnection: connection to 'localhost' socket 3, errormsg 'No Error' lp: Link_send: host 'localhost' socket 3, timeout 6000 lp: Link_send: str '^Blp ', count 4, ack 0xbfbfc3d0 lp: Link_send: final status NO ERROR lp: Link_send: host 'localhost' socket 3, timeout 6000 lp: Link_send: str '^B142 cfA065h110.private ', count 24, ack 0xbfbfbf90 lp: Link_send: final status NO ERROR lp: Link_send: host 'localhost' socket 3, timeout 6000 lp: Link_send: str 'Hh110.private Ppapowell J/tmp/hi CA Lpapowell Apapowell@h110+65 D2001-10-18-05:34:18.939 Qlp N/tmp/hi fdfA065h110.private UdfA065h110.private ', count 143, ack 0xbfbfbf90 lp: Link_send: final status NO ERROR lp: Link_send: host 'localhost' socket 3, timeout 6000 lp: Link_send: str '^C3 dfA065h110.private ', count 22, ack 0xbfbfbf24 lp: Link_send: final status NO ERROR lp: Link_send: host 'localhost' socket 3, timeout 6000 lp: Link_send: str '', count 1, ack 0xbfbfbf24 lp: Link_send: final status NO ERROR
The &lpr;
Debugging &lpq h110: {1} % lpq -= lpq: Illegal option '=' usage: lpq [-aAclV] [-Ddebuglevel] [-Pprinter] [-tsleeptime] -A - use authentication specified by AUTH environment variable -a - all printers -c - clear screen before update -l - increase (lengthen) detailed status information additional l flags add more detail. -L - maximum detailed status information -n linecount - linecount lines of detailed status information -Ddebuglevel - debug level -Pprinter - specify printer -s - short (summary) format -tsleeptime - sleeptime between updates -V - print version information h110: {2} % lpq -D1 2001-10-18-05:39:09 [8090] Initialize: /dev/null fd 3 2001-10-18-05:39:09 [8090] initsetproctitle: using builtin 2001-10-18-05:39:09 [8090] lpq Setup_uid: OriginalEUID 0, OriginalRUID 1001 ... h110: {3} % lpq -Dnetwork lp: getconnection: START host localhost, timeout 10, connection_type 1 lp: getconnection: fqdn found localhost.my.domain, h_addr_list count 1 lp: Link_dest_port_num: port 515 = 515 lp: getconnection: AGAIN port 862, min 512, max 1023, count 0, connects 0 lp: Link_dest_port_num: port 515 = 515 lp: getconnection: sock 3, src ip 127.0.0.1, port 862 ...
The &lpq;, &lprm;, and &lpc; applications also support the What Went Wrong With My Job?
Basic &lpq; Information h110: {1} % lpr /tmp/hi h110: {1} % lpq Printer: lp@h110 Queue: 1 printable job Server: pid 8741 active Unspooler: pid 8742 active Status: processing 'dfA740h110.private', size 3, format 'f', IF filter 'ifhp' at 08:16:58.465 Filter_status: code = 10003, 'Warming Up' at 08:17:02.045 Rank Owner/ID Class Job Files Size Time active papowell@h110+740 A 740 /tmp/hi 3 08:16:58
The first thing to do is check the status of your job with &lpq;. This will show the current jobs in the queue and &lpd; server. The
Using the &lpq; -l Option h110: {2} % lpq -l Printer: lp@h110 Queue: 1 printable job Server: pid 8741 active Unspooler: pid 8742 active Status: printing job 'papowell@h110+740' at 08:16:58.465 Status: processing 'dfA740h110.private', size 3, format 'f', IF filter 'ifhp' at 08:16:58.465 Filter_status: getting end using 'pjl job/eoj' at 08:16:59.902 Filter_status: code = 10003, 'Warming Up' at 08:17:02.045 Rank Owner/ID Class Job Files Size Time active papowell@h110+740 A 740 /tmp/hi 3 08:16:58 h110: {3} % lpq -lll Printer: lp@h110 Queue: 1 printable job Server: pid 8741 active Unspooler: pid 8742 active Status: accounting at start at 08:16:58.455 Status: opening device 'h14%9100' at 08:16:58.455 Status: printing job 'papowell@h110+740' at 08:16:58.465 Status: processing 'dfA740h110.private', size 3, format 'f', IF filter 'ifhp' at 08:16:58.465 Filter_status: data sent at 08:16:59.902 Filter_status: sent job file at 08:16:59.902 Filter_status: getting end using 'pjl job/eoj' at 08:16:59.902 Filter_status: code = 10003, 'Warming Up' at 08:17:02.045 Rank Owner/ID Class Job Files Size Time active papowell@h110+740 A 740 /tmp/hi 3 08:16:58
The &lpq;
Using the &lpq; -L Option h110: {4} % lpq -L Printer: lp@h110 Queue: 1 printable job Server: pid 8741 active Unspooler: pid 8742 active Status: waiting for subserver to exit at 08:16:58.451 Status: subserver pid 8742 starting at 08:16:58.455 Status: accounting at start at 08:16:58.455 Status: opening device 'h14%9100' at 08:16:58.455 Status: printing job 'papowell@h110+740' at 08:16:58.465 Status: processing 'dfA740h110.private', size 3, format 'f', IF filter 'ifhp' at 08:16:58.465 ..... Filter_status: decoded job type 'PCL' at 08:16:59.901 Filter_status: job type 'PCL' at 08:16:59.901 Filter_status: transferring 3 bytes at 08:16:59.902 Filter_status: 100 percent done at 08:16:59.902 Filter_status: data sent at 08:16:59.902 Filter_status: sent job file at 08:16:59.902 Filter_status: getting end using 'pjl job/eoj' at 08:16:59.902 Filter_status: code = 10003, 'Warming Up' at 08:17:02.045 ..... Rank Owner/ID Class Job Files Size Time active papowell@h110+740 A 740 /tmp/hi 3 08:16:58
If you want to see
Job Completion h110: {5} % lpq Printer: lp@h110 Queue: no printable jobs in queue Status: job 'cfA740h110.private' removed at 08:18:07.776 Filter_status: done at 08:18:07.756 h110: {6} % lpq -lll Printer: lp@h110 Queue: no printable jobs in queue Status: printing job 'papowell@h110+740' at 08:16:58.465 Status: processing 'dfA740h110.private', size 3, format 'f', IF filter 'ifhp' at 08:16:58.465 Status: IF filter 'ifhp' filter finished at 08:18:07.757 Status: printing finished at 08:18:07.757 Status: accounting at end at 08:18:07.774 Status: finished 'papowell@h110+740', status 'JSUCC' at 08:18:07.774 Status: subserver pid 8742 exit status 'JSUCC' at 08:18:07.775 Status: lp@h110.private: job 'cfA740h110.private' printed at 08:18:07.775 Status: job 'cfA740h110.private' removed at 08:18:07.776 Filter_status: transferring 3 bytes at 08:16:59.902 Filter_status: 100 percent done at 08:16:59.902 Filter_status: data sent at 08:16:59.902 Filter_status: sent job file at 08:16:59.902 Filter_status: getting end using 'pjl job/eoj' at 08:16:59.902 Filter_status: code = 10003, 'Warming Up' at 08:17:02.045 Filter_status: end of job detected at 08:18:06.457 Filter_status: pagecounter 105341 after 1 attempts at 08:18:07.756 Filter_status: pagecounter 105341, pages 1 at 08:18:07.756 Filter_status: done at 08:18:07.756
When your job is finished, you can use the
Summary Status Displays h110: {7} % lpq -s lp@h110 0 jobs h110: {239} % lpq -s -a lp@h110 0 jobs lp0@h110 0 jobs (printing disabled) h110: {8} % lpc status Printer Printing Spooling Jobs Server Subserver Redirect Status/(Debug) lp@h110 enabled enabled 0 none none h110: {9} % lpc status all Printer Printing Spooling Jobs Server Subserver Redirect Status/(Debug) lp@h110 enabled enabled 0 none none lp0@h110 disabled enabled 0 none none h110: {10} % exit
The The Diagnostics for &lpd; Problems
&lpd; Options h110# lpd -= lpd: Illegal option '=' usage: lpd [-FV] [-D dbg] [-L log] Options -D dbg - set debug level and flags Example: -D10,remote=5 set debug level to 10, remote flag = 5 -F - run in foreground, log to STDERR Example: -D10,remote=5 -L logfile - append log information to logfile -V - show version info h110# lpd -D= debug usage: -D [ num | flag=num | flag=str | flag | flag@ | flag+N ]* flags recognized: network[+N,@], database[+N,@], lpr[+N,@], lpc[+N,@], lprm[+N,@], lpq[+N,@], log[+N,@], test=num
The &lpd; server can be started in debug mode. However, the amount of information produced can be overwhelming. If you need to determine what is happening during initial connection, then you will have to do this.
Using &lpd; Debug Options h110# lpd h110# lpd -F -D1 2001-10-18-05:56:55 [8156] lpd Initialize: starting ... 2001-10-18-05:56:55.228 h110 [8156] lpd lpd: listening socket fd -6 Fatal error - Another print spooler is using TCP printer port, possibly lpd process '8154' 2001-10-18-05:56:55.228 h110 [8156] lpd cleanup: done, exit(1) h110# killall lpd h110# lpd -F -D1 2001-10-18-05:57:05 [8158] lpd Initialize: starting ... 2001-10-18-05:57:05.800 h110 [8159] Waiting lpd: LOOP START 2001-10-18-05:57:05.800 h110 [8159] Waiting lpd: starting select timeout 'yes', 600 sec, max_socks 7 ---- other window h110: {5} % lpr /tmp/hi ---- 2001-10-18-05:57:44.341 h110 [8159] Waiting lpd: select returned 1, error 'No Error' 2001-10-18-05:57:44.342 h110 [8159] Waiting lpd: fd 5 readable 2001-10-18-05:57:44.342 h110 [8159] Waiting lpd: connection fd 8 2001-10-18-05:57:44.351 h110 [8159] Waiting Start_worker: fd 8 2001-10-18-05:57:44.356 h110 [8171] RECV lp: Fix_Rm_Rp_info: printer name 'lp' 2001-10-18-05:57:44.356 h110 [8171] RECV Reset_config: starting 2001-10-18-05:57:44.361 h110 [8171] RECV lp: Select_pc_info: looking for 'lp', depth 0 ...
This shows
Debugging Spool Queue Printcap: lp:sd=/var/spool/lpd/%P :db=
The &checkpc; program creates a standard set of files in each spool queue, including the
Setting Queue Debug Options h110# vi /etc/printcap set: lp:... :db=lpr h110# lpc reread lpd server pid 8200 on h110.private, sending SIGHUP
Edit the printcap. You can then use
<literal/log/ File 2001-10-18-06:11:30.349 h110 [8216] RECV lp: Receive_job: debug 'lpr', Debug 0, DbgFlag 0x1000 2001-10-18-06:11:30.349 h110 [8216] RECV lp: Receive_job: spooling_disabled 0 2001-10-18-06:11:30.349 h110 [8216] RECV lp: Receive_job: sending 0 ACK for job transfer request 2001-10-18-06:11:30.349 h110 [8216] RECV lp: Receive_job: from localhost.my.domain- getting file transfer line 2001-10-18-06:11:30.349 h110 [8216] RECV lp: Receive_job: read from localhost.my.domain- status 0 read 23 bytes '^B131 cfA215h110.private'
You can now use the Printers
Printer Types Printers: Cheap and Slow Ink Dispensers Not So Cheap Fast Printers Vintage Stuff On Sale Legacy Junk You Are Stuck With
Your office mate has just purchased a nice new $99 ink-jet printer and wants to use it on his office desktop. Your boss calls you in and tells you that the new With your luck, probably all three happen on the same day. Welcome to the wonderful world of printers. Interface
Interface Types Connection: Parallel port : write only (no status) read/write (maybe you get status) Serial port: read/write (status) Network: serial port emulator parallel port emulator print spooler emulator whacko interface
The type of interface on your printer is usually a function of the printer cost and speed. The low cost/low speed printers usually have a parallel port interface, while the higher cost/higher speed printers usually have both a parallel port Parallel Port
Parallel Port
Some printers provide In a fit of desperation, the IEEE1284 standard (well, actually 3 standards) were developed to allow at least some sort of general consensus on how a bidirectional parallel port should work. If you are interested in the details about Parallel Ports, see http://www.fapo.com/1284int.htm for a nice introduction, and the IEEE1394 Trade Association Home Page http://www.1394ta.com/ for pointers to other information. The good news is that if your printer is IEEE1284 compliant, then it has a functional bidirectional interface that will return status and other information. The bad news, Given this set of problems I recommend that you: Put only one device (your printer) on each parallel port. Do not expect to get status information back from the printer.
Parallel Port Printcap lp:lp=/dev/lpt0 :sd=/var/spool/lpd/%P
As shown in , the printcap entry for a parallel port (without a filter) is really simple. If your printer is offline or powered down, &lpd; will not be able to open the parallel port and you will see an endless list of error messages in the status file.
Loading Linux Parallel Port Driver [papowell@h112 papowell]$ su Password: [root@h112 papowell]# echo </dev/lp0 [root@h112 papowell]# cd /proc/sys/dev/parport/ [root@h112 parport]# ls default parport0 [root@h112 parport]# cd parport0 [root@h112 parport0]# ls autoprobe autoprobe0 autoprobe1 autoprobe2 autoprobe3 base-addr devices dma irq modes spintime [root@h112 parport0]# cat autoprobe CLASS:PRINTER; MODEL:DESKJET 670C; MANUFACTURER:HEWLETT-PACKARD; DESCRIPTION:Hewlett-Packard DeskJet 670C; COMMAND SET:MLC,PCL,PML;
The Linux system uses loadable module drivers for the parallel ports and newer releases support the IEEE1284 to load the modules; the echo </dev/lp0 command tries to open the device in /proc system installed, then you can see what the IEEE1284 probe function returned.
Parallel Port Problems One Interrupt per Output Character - One Interrupt per Blocks of Characters (DMA) - Hope that DMA works May operate by
While you may think that you are getting a high throughput to the parallel port, in actual fact it may be very slow. In the worst case you will get a an interrupt for every character output. Even worse, sometimes the parallel port driver will To add insult to injury, some systems do not even support interrupts with their parallel port hardware. To do IO, they periodically Network Ports
Network Ports
Most devices that support a network connection do so by either providing support for a print spooler interface (&lpd) or by emulating a bidirectional connection to the printing device (
Network Port Printcap lp:lp=10.0.0.14%9100 :sd=/var/spool/lpd/%P lp2:lp=raw@10.0.0.14 :sd=/var/spool/lpd/%P # legacy :rp:rm support # :rp=raw:rm=10.0.0.14
The printcap for a network printer is shown in . You can use the
Benefits of Network Port Printcap High Speed Low Error Rate (+ Error Detection) Long Distances Very low system overhead
Network port printing is effectively the highest speed. The TCP/IP protocol provides both flow control and error detection/correction. The printer and host system can be separated by quite large distances. Finally, the overhead of the TCP/IP connection is very low in terms of hardware and software.
Network Print Server
If you have legacy systems that have serial or parallel ports, you can buy a Network Print Server Configuration Information ManufacturerModelRFC1179 Port Name (rp=XXX)Send to TCP portCannon PrinterCannon 460 PS, no hard drive- Unknown if supported -Cannon 460 PS hard drivexjprint - print immediately,xjhold - print later- Unknown if supported -Digital Products Inc.NETPrint Print ServerPORTn, where n is port on server- Unknown if supported -Electronics For Imaging Inc.Fiery RIP i seriesnormalq or urgentq- Unknown if supported -Fiery RIP XJ seriesxjprint- Unknown if supported -Fiery RIP XJ+ and SI seriesprint_Model, e.g. print_DocuColor- Unknown if supported -Fiery models ZX2100, ZX3300, X2, X2eprint- Unknown if supported -Emulex Corp.NETJet/NETQue print server- Unknown if supported -Extended Systems Inc.ExtendNet Print ServerPrintern, where n is port on server- Unknown if supported -Hewlett-PackardJetDirect interface cardraw9100Hewlett-PackardJetDirect Multiport Serverport 1 - raw1, port 2 - raw2, etc.port 1 - 9100, port 2 - 9101, etc.I-DataEasycom 10 Printserverpar1 (parallel port 1)- Unknown if supported -Easycom 100 PrintserverLPDPRT1- Unknown if supported -IBMNetwork Printer 12, 17, 24, and 24PS- Unknown if supported -LantronixEPS1, EPS2EPS_X_S1 (serial) port 1, EPS_X_P1 (parallel) port 2, etc.3001 (port 1), 3002 (port 2), etc.QMSVarious ModelsRAW35 (AppSocket)TektronixTektronix printer network cardsPS (PostScript), PCL (PCL), or AUTO(Auto-selection between PS, PCL, or HPGL). Not reliable.9100 (AppSocket on some models)Rose ElectronicsMicroserve Print Serverslp9100XeroxModels 4505, 4510, 4517, 4520PASSTHRU2501 (AppSocket on some models)Model 4512PORT110001 (programmable)Model N179100Models N24 and N322000Models 4900, 4915, 4925, C55PS2000Document Centre DC220/230lp- Unknown if supported -
All company, brand, and product names are properties of their respective owners. Sending To SMB (Samba, Microsoft) Printer, Novell, Appletalk
Using Program To Send To Printer
There are a wide number of other print spooling systems that have been developed over the years. Most of these use proprietary or arcane protocols to transfer files. These include the
Protocols, Packages, and Transfer Programs Protocol Package Transfer Program SMB (CIFS) Samba smbclient + wrapper WWW: http://www.samba.org Novell Netware ncpfs (Linux) nprint + wrapper FTP: ftp.gwdg.de/pub/linux/misc/ncpfs (Also Linux Kernel Documentation/filesystems) Appletalk CAPS pap + wrapper WWW: http://sourceforge.net/projects/netatalk WWW: http://www.umich.edu/~rsug/netatalk
Each of these programs will transfer a print job to a remote system.
Printcap For Transfer Programs lp:
You can specify a
Samba <application/smbclient/ Wrapper #!/bin/sh # configuration smbclient=/usr/local/bin/smbclient # get options from $PRINTCAP_ENTRY environment variable PATH=/bin:/usr/bin:/usr/local/bin options=`echo "${PRINTCAP_ENTRY}" | sed -n 's/:options=//p' ` echo OPTIONS $options >&2 if [ -n "$options" ] ; then # paranoia: $options=`echo |perl -sp 's/[^\w\s,-+%="\']/ /'` eval dummy=v `echo $options`; fi if [ "$oldversion" != "" -a "$authfile" != "" -a -f "$authfile" ] ; then . $authfile; $authfile= fi if [ "$translate" = "yes" ]; then command="translate ; print -" else command="print -" fi if [ "$share" = "" ] ; then share="//$host/$printer" ; fi echo $smbclient "$share" ${password:+password} -E \ ${username:+-U} ${username:+username} ${hostip:+-I} \ $hostip -N ${workgroup:+-W} $workgroup \ ${authfile:+-A} $authfile -c "$command" >&2 $smbclient "$share" ${password} -E \ ${username:+-U} ${username} ${hostip:+-I} \ $hostip -N ${workgroup:+-W} $workgroup \ ${authfile:+-A} $authfile -c "$command" >&2
The ). The value is scanned for the
<literal/$PRINTCAP_ENTRY/ lp: :lp=|/usr/local/lib/filters/smbprint :options=authfile="auth" host="h114" printer="lp" workgroup="ASTART"
There older versions of the Finally, we echo the command for logging purposes (note that
Novell and Appletalk Wrappers ncpprint: .... usercmd="" if [ "$username" != "" ]; then if [ "$password" != "" ]; then usercmd="-U $username -P $password" else usercmd="-U $username -n" fi fi nprint=/usr/bin/nprint -S $server -q $printer \ $usercmd -N - 2>/dev/null atalkprint: ... /usr/bin/pap -p "$username:$printer@$host"
This general template can also be used with the Serial Port
Serial Port
A serial line is usually bidirectional in operation, but there are very few printers that will return status information. The most notable exception to this are
Serial Port Printcap lp:lp=/dev/tty00 :stty=raw crtscts 19200 :sd=/var/spool/lpd/%P # optional Open Read Write #:rw
The As you might suspect, the serial port is limited by the line speed. In addition, it has a higher rate of errors than you might expect. Most printers that use a serial port are for Printer Job Formats
Page Description Lanaguages Printer Input File Formats: Postscript (Level 1, 2, 3) PCL (PCL 5) Text (Really Legacy PCL) PJL Configuration Specification for Job - PostScript or PCL or HPGL or ... Magic Mystery Proprietary Format
Most printers will only print jobs that have a particular format. These formats are called
How To Identify Print Formats Print Job Job Types Start of File File Type %! PostScript - Level Unknown %!PS-Adobe-1.0 PostScript - Level 1.0 %!PS-Adobe-2.0 PostScript - Level 2.0 %!PS-Adobe-2.1 PostScript - Level 2.0 %!PS-Adobe-3.0 PostScript - Level 2.0 \033%-12345X@PJL HP Printer Job Language data \033E\033 HP PCL printer data This ... Text
The type of file can be identified by looking at the content near the start of the file. This is how the .
Using the <application/file/ Application h110: {1} % file * Makefile: ASCII English text atalkprint: Bourne shell script text executable logo.gif: GIF image data, version 89a, 250 x 91, one.pcl: HP PCL printer data one.ps: PostScript document text conforming at level 3.0 one.pjl: HP Printer Job Language data rewindstdin: ELF 32-bit LSB executable testpage-a4.fig: FIG image text, version 3.1 testpage-a4.ps: PostScript document text conforming at level 2.0 testpage.fig: FIG image text, version 3.1
PostScript
One PostScript Page %!PS-Adobe-3.0 %% one page (i.e. - a page with a 1 on it) %%/Times-Roman /Courier findfont 200 scalefont setfont 72 300 moveto (1) show showpage -- from PostScript Reference Manual 1986 Adobe (www.adobe.com)
This is an example of a PostScript File.
Generate One Page h110: {1} % echo 1 |groff -Tps >/tmp/one.ps h110: {2} % more /tmp/one.ps %!PS-Adobe-3.0 %%Creator: groff version 1.16.1 %%CreationDate: Thu Oct 18 12:48:45 2001 %%DocumentNeededResources: font Times-Roman %%DocumentSuppliedResources: procset grops 1.16 1 %%Pages: 1 %%PageOrder: Ascend %%Orientation: Portrait %%EndComments %%BeginProlog %%BeginResource: procset grops 1.16 1 /setpacking where{ pop currentpacking true setpacking }if /grops 120 dict dup begin /SC 32 def /A/show load def /B{0 SC 3 -1 roll widthshow}bind def
The quick way to generate a test page is use
PostScript Document Structuring Conventions Specifies how a PostScript print job should be formatted Divides the job up into a
Most document generation systems produce PostScript that meets the PostScript Document Structuring Convention. This allows you to
Tools for PostScript Document Manipulation GhostScript - format conversion WWW: http://www.ghostscript.com PSUtils - utilities to massage PostScript by Angus Duggan FTP: ftp://ftp.dcs.ed.ac.uk/pub/ajcd/ WWW: http://www.dcs.ed.ac.uk/home/ajcd/psutils/ psbook rearranges pages into signatures psselect selects pages and page ranges pstops performs general page rearrangement and selection psnup put multiple pages per physical sheet of paper psresize alter document paper size epsffit fits an EPSF file to a given bounding box getafm (sh) outputs PostScript to retrieve AFM file from printer showchar (sh) outputs PostScript to draw a character with metric info fixdlsrps (perl) filter to fix DviLaser/PS output so that PSUtils works fixfmps (perl) filter to fix framemaker documents so that psselect etc. work fixmacps (perl) filter to fix Macintosh documents with saner version of md fixpsditps (perl) filter to fix Transcript psdit documents to work with PSUtils fixpspps (perl) filter to fix PSPrint PostScript so that psselect etc. work fixscribeps (perl) filter to fix Scribe PostScript so that psselect etc. work fixtpps (perl) filter to fix Troff Tpscript documents fixwfwps (perl) filter to fix Word for Windows documents for PSUtils fixwpps (perl) filter to fix WordPerfect documents for PSUtils fixwwps (perl) filter to fix Windows Write documents for PSUtils extractres (perl) filter to extract resources from PostScript files includeres (perl) filter to include resources into PostScript files psmerge (perl) hack script to merge multiple PostScript files
The combination of GhostScript and PSutils by Angus Duggan are a powerful combination.
Selection of Pages + 4up Printing h110: {81} % psselect -p20-24 LPRng-HOWTO.ps | psnup -4 >p4up.ps [20] [21] [22] [23] [24] Wrote 5 pages, 38404 bytes [1] [2] Wrote 2 pages, 42769 bytes
PostScript Output
End Of PostScript Job: ^D (CTRL-D) ^D is recognized as an 'end of job' - causes reset of PostScript interpreter to defaults ^D%!PS-Adobe-3.0 ... ^D The Dreaded ^D at Start of Job - causes problems Rest of job may be ignored! Solution: strip off ^D at start (ifhp = ps_eoj_at_start@) The Dreaded ^D at End of Job - causes problems when you are trying to massage postscript or append jobs Solution: strip off ^D everywhere (ifhp = ps_eoj_at_end@)
The PCL
One PCL Page ^[E^[&u600D^[&l2A^[&l0O^[&l0E^[(0N^[(s1p0s0b4101T ^[(s24V^[*p655x942Y1^L^[E Note: ^[ is ESC or \033 ^[E is 'reset printer configuration'
This is an example of a PCL file. Note that the file starts with
Generate One Page h110: {1} % echo 1 | groff -Tlj4 >/tmp/one.pcl h110: {2} % more ^[E^[&u600D^[&l2A^[&l0O^[&l0E^[(0N^[(s1p0s0b4101T ^[(s24V^[*p655x942Y1^L^[E
The quick way to generate a test page is use Printer Job Language (PJL) and PostScript, PCL
PJL Example ^[%-12345X@PJL @PJL RDYMSG DISPLAY = ":" @PJL USTATUSOFF @PJL USTATUS JOB = ON @PJL USTATUS DEVICE = ON @PJL USTATUS PAGE = ON @PJL USTATUS TIMED = 10 @PJL ENTER LANGUAGE = POSTSCRIPT ^D%! %!PS-Adobe-3.0 %% one page (i.e. - a page with a 1 on it) %%/Times-Roman /Courier findfont 200 scalefont setfont 72 300 moveto (1) show showpage ^D^[%-12345X@PJL @PJL RDYMSG DISPLAY = ":" @PJL EOJ NAME = ":" @PJL USTATUSOFF @PJL USTATUS JOB = ON @PJL USTATUS DEVICE = ON @PJL USTATUS PAGE = ON @PJL USTATUS TIMED = 10 @PJL RDYMSG DISPLAY = "Done: :" ^[%-12345X
Printer Job Language is used to set up configuration and other facilities for a printer. It can establish defaults for printing and provide direction to the printer on how to handle job items not specified by the PostScript or PCL language. The PJL Reset command Text Files
Text Files and The Jaggies Text - usually ASCII characters The Dreaded Jaggies File: This is what you see on the printer Printer output: This is what you see on the printer
Text is usually just ASCII characters. Unix lines are terminated with new line (
Fixing The Jaggies Fixing The Jaggies: Convert NL to CR/NL Quick and Dirty sed -e 's/$/\r/' OR lpf (&LPRng; utility) Make PCL Printer Interpret CR as CR/LF ^[E -> ^[E&k2G Remove the PCL Reset and add the &k2G (CR -> CR/LF command)
Magical Mystery Proprietary Format
Magical Mystery Formats Magical Mystery Proprietary Format - Usually a RASTER format - legacy devices such as Versatek Plotters - new super cheap InkJet Printers The host system needs to do conversion to raster file - Dirty Little Secret - some of these understand PCL Level 5 (monochrome) and are compatible with HP LaserJet 4.
You should try and see if your printer understands PCL. Try using GhostScript with the
GhostScript To The Rescue h110: {64} % gs --help AFPL Ghostscript 6.50 (2000-12-02) Copyright (C) 2000 Aladdin Enterprises, Menlo Park, CA. All rights reserved. Usage: gs [switches] [file1.ps file2.ps ...] Most frequently used switches: (you can use # in place of =) -dNOPAUSE no pause after page | -q `quiet', fewer messages -g<width>x<height> page size in pixels | -r<res> pixels/inch resolution -sDEVICE=<devname> select device | -dBATCH exit after last file -sOutputFile=<file> select output file: - for stdout, |command for pipe, embed %d or %ld for page # Input formats: PostScript PostScriptLevel1 PostScriptLevel2 PDF
You can read PostScript level 1, 2, or PDF with this version of GhostScript.
GhostScript Devices Available devices: x11 bbox x11alpha x11cmyk x11cmyk2 x11cmyk4 x11cmyk8 x11gray2 x11gray4 x11mono x11rg16x x11rg32x atx23 atx24 atx38 deskjet djet500 fs600 laserjet ljetplus ljet2p ljet3 ljet3d ljet4 ljet4d lp2563 oce9050 lj5mono lj5gray epswrite pswrite pdfwrite pxlmono pxlcolor bit bitrgb bitcmyk bmpmono bmpgray bmpsep1 bmpsep8 bmp16 bmp256 bmp16m bmp32b cgmmono cgm8 cgm24 jpeg jpeggray miff24 pcxmono pcxgray pcx16 pcx256 pcx24b pcxcmyk pcx2up pbm pbmraw pgm pgmraw pgnm pgnmraw ppm ppmraw pnm pnmraw pkm pkmraw pksm pksmraw plan9bm pngmono pnggray png16 png256 png16m psmono psgray psrgb faxg3 faxg32d faxg4 tiffcrle tiffg3 tiffg32d tiffg4 tifflzw tiffpack tiff12nc tiff24nc appledmp iwhi iwlo iwlq bj10e bj200 ccr cdeskjet cdjcolor cdjmono cdj500 cdj550 declj250 dnj650c lj4dith pj pjxl pjxl300 bjc600 bjc800 escp djet500c cljet5 cljet5pr cljet5c lj3100sw coslw2p coslwxl cp50 epson eps9mid eps9high ibmpro epsonc ap3250 st800 stcolor uniprint lj250 paintjet pjetxl hl7x0 imagen jetp3852 lbp8 lips3 lp8000 m8510 necp6 lq850 lxm5700m oki182 okiibm photoex sj48 t4693d2 t4693d4 t4693d8 tek4696 cfax dfaxlow dfaxhigh cif inferno mgrmono mgrgray2 mgrgray4 mgrgray8 mgr4 mgr8 sgirgb sunhmono cdj850 hpdj pcl3 hpdjplus hpdjportable hpdj310 hpdj320 hpdj340 hpdj400 hpdj500 hpdj500c hpdj510 hpdj520 hpdj540 hpdj550c hpdj560c hpdj600 hpdj660c hpdj670c hpdj680c hpdj690c hpdj850c hpdj855c hpdj870c hpdj890c hpdj1120c cdj970 stp nullpage
GhostScript converts PostScript to a wide range of output device formats. The interesting ones are
GhostScript Support http://www.ghostscript.com http://www.cs.wisc.edu/~ghost http://www.cs.wisc.edu/~ghost/doc/printer.htm http://www.cs.wisc.edu/~ghost/doc/AFPL/devices.htm
The http://www.ghostscript.com site has links to just about everything concerned with GhostScript. the http://www.cs.wisc.edu/~ghost site mirrors much of this information. The printer.htm and devices.htm are good sources for information about printing. Printing Test Pages
Printing Test Pages To Parallel Port #!/bin/sh for i in one.pcl one.pjl one.ps ; do cat $i >/dev/lp0 done
The easiest way to print the test pages is to try them all. This is brutal, but you may need to do it at least once.
Using Netcat (<application/nc/) nc - Netcat by Mudge http://www.avian.org/ ftp://ftp.lprng.com/pub/LPRng/TOOLS/netcat #!/bin/sh for i in one.pcl one.pjl one.ps ; do nc -w10 10.0.0.14 9100 <$i done h110: {453} % sh -x /tmp/testnc + nc -w10 -v -v 10.0.0.14 9100 h14.private [10.0.0.14] 9100 (jetdirect) open @PJL USTATUS DEVICE CODE=10003 DISPLAY="02 WARMING UP" ONLINE=TRUE ... @PJL USTATUS TIMED CODE=10001 DISPLAY="Done: papowell /" ONLINE=TRUE ^C
Netcat is a handy tool for testing network connections to a printer. You can also use it as a port mapper and find out what interesting ports are open on your print spooler box. Filters
Filters
A filter is responsible for converting the job data files to a format compatible with the printer, transfering the job to the printer, and monitoring for any problems.
Filter Specification in Printcap Entry # &LPRng; lp: :filter=/.../filter # Legacy BSD (&LPRng; is backwards compatible) lp: # file 'format' is lower case letter X, filter is # 'Xf' option value, default format is 'f' so default # filter is 'if' :if=/.../filter :hf=/.../filter
The legacy BSD printing system required you to specify a filter for all input types. LPRng uses
Specifying Job Datafile Format &LPRng 'format' selection: h110: {295} % lpr -Fx /tmp/hi Legacy BSD 'format' selection: h110: {295} % lpr -x /tmp/hi Format 'b' (Binary) or 'l' (Literal) for 'Passthrough' Operation - format 'l' is used h110: {295} % lpr -l /tmp/hi h110: {295} % lpr -b /tmp/hi Control file example: Hh110.private J/tmp/hi Lpapowell N/tmp/hi fdfA383h110.private <- first letter is format UdfA383h110.private
The &lpr; In the control file, lines starting with lower case letters specify a format and the data file to print with the format.
Filter Execution Environment lp:sd=/var/spool/lpd/%P :filter=/filter :lp=/dev/lp Execution: CWD is spool directory (/var/spool/lpd/lp) Environment: PATH=... - from &conf; LD_LIBRARY_PATH=... - from &conf; PRINTER=lp PRINTCAP_ENTRY=lp: - printcap entry :sd=/var/spool/lpd/lp with %P fixed up :filter=/filter :lp=/dev/lp CONTROL=Aroot@h110+383 - job control file CA D2001-10-19-06:40:59.968 Hh110.private J/tmp/hi Lroot Proot Qlp N/tmp/hi fdfA383h110.private UdfA383h110.private HF=A=root@h110+383 - job control file C=A D=2001-10-19-06:40:59.968 H=h110.private J=/tmp/hi priority=B transfername=cfA383h110.private
The for an example of this use. The
Command Line Options lp:sd=/var/spool/lpd/%P :filter=/filter :lp=/dev/lp /filter <dfA383h110.private >/dev/lp
The filter command line options are really agressive due to history and feeping creaturism. All of the lines in the control file with a capital letter are passed as shown, the
Filter Exit Codes Exit Code Action 0 (JSUCC) Successful, send filter output to printer 1 (JFAIL) Failed, retry later 2 (JABORT) Failed, do not retry, and Abort printing 3 (JREMOVE) Remove job 4 (JHOLD) Set job HOLD flag
The filter program exit codes can be used to control how the job is processed. The
Solid As A Rock Filter Operation Filter: - examines input format using CR/LF - if printer can reports status, then gets status as it does the transfer operation. - after transferring job, sends more magic cookies to tell printer that job is over - monitors printer for error status - exits with an appropriate error code telling exactly what problems (if any) were encountered.
This is what a real filter should do. Note that it appears to be obvious that you would need to do all this.
Solid As A Used Paper Coffee Filter Operation Filter: - Tosses job at GhostScript for conversion, sets GhostScript output to STDOUT - Returns GhostScript exit status
OK, I am being a bit harsh. But this is not too far from the truth. Most filter packages are somewhere between the two extremes. Writing Your Own Filter If you want to write your own filter you can start with the following simple examples. In practice you have two choices:
Filter Template in <application/perl/ #!/usr/bin/perl use Getopt::Std; my $debug = 0; # always... sigh... my(%opt, @pc, %options); # get command line options getopts( 'A:B:C:D:E:F:G:H:I:J:K:L:M:N:O:P:Q:R:T:S:U:V:W:X:Y:Z:' . 'a:b:cd:e:f:g:h:i:j:k:l:m:n:o:p:q:r:t:s:u:v:w:x:y:z:', \%opt ); while( @ARGV ){ $opt{acct} = pop @ARGV ; }; # split up the PRINTCAP_ENTRY environment variable value @pc = split /\n\s*:/s, ($ENV{PRINTCAP_ENTRY} || ""); shift @pc; # throw way first entry field, printer name # set the options foreach (@pc){ # set the options values if( /^(.+)=(.*)/ ){ $options{$1} = $2; } elsif ( /^(.+)@/ ){ $options{$1} = 0; } else { $options{$_} = 1; } } if( $debug ){ # for those interested my $s = ""; foreach my $v (sort keys %options ){ $s .= "$v='$options{$v}',"; } print STDERR "Printcap: '$s'\n"; $s=""; foreach my $v (sort keys %opt){ $s .= "$v='$opt{$v}',"; } print STDERR "Args: '$s'\n"; }
This example shows how to get the various environment variables and command line options and put them into handy
How To Determine The Type of Job File my $file = `/usr/bin/file -`; # we find the file type chomp $file; print STDERR "File: '$file'\n" if $debug; # show the file type sysseek STDIN,0,0 or die "cannot seek STDIN - $!"; # rewind to start of file my $is_postscript = ($file =~ /PostScript/i); print STDERR "Postscript: '$is_postscript'\n" if $debug; # show the file type if( $is_postscript ){ my $status = system "/usr/local/bin/psnup", "-4"; if( $status ){ print STDERR "psnup failed - $!\n"; exit 1; } exit 0; } while( <STDIN> ){ print }; exit 0;
To determine the file type we use the
Printcap for Filter nup:force_localhost :filter=/usr/local/libexec/filters/nup :sd=/var/spool/lpd/%P :lp=lp@localhost (Don't forget to run checkpc!)
We set make a printcap entry. Note the use of
Using Filter With $debug=1 Status: processing 'dfA946h110.private', size 145, format 'f', IF filter 'nup' at 07:27:30.938 Status: IF filter 'nup' filter msg - 'Printcap: 'cm='Class Test Printer 1',.... Status: IF filter 'nup' filter msg - 'Args: 'A='papowell@h110+946',C='A',.... Status: IF filter 'nup' filter msg - 'File: 'standard input: PostScript document' at 07:27:30.938 Status: IF filter 'nup' filter msg - 'Postscript: '1'' at 07:27:30.938 Status: IF filter 'nup' filter msg - 'Wrote 0 pages, 1775 bytes' at 07:27:30.940 Status: IF filter 'nup' filter finished at 07:27:30.941 Status: sending job 'papowell@h110+946' to lp@localhost at 07:27:30.943
shows the status output when we set the
Using Filter With $debug=0 Status: processing 'dfA021h110.private', size 145, format 'f', IF filter 'nup' at 07:38:22.416 Status: IF filter 'nup' filter msg - 'Wrote 0 pages, 1775 bytes' at 07:38:22.472 Status: IF filter 'nup' filter finished at 07:38:22.473 Status: sending job 'papowell@h110+21' to t6@localhost at 07:38:22.475
shows the status output when we set the The &LPRng; IFHP Filter
&ifhp &ifhp; (IFHP) part of the &LPRng; suite separate from &LPRng; not quite as strong as a brick, but better than a wet paper coffee filter. ifhp.conf contains printer configuration information
The &ifhp; filter is part of the LPRng family of programs. It is distributed separately because the release and update times did not orginally match. The &ifhp; filter is intended for use with the &LPRng; software and undergoes much of the same testing.
ifhp.conf Configuration Information ### Supported Printers ### default - HP 4M Plus, PostScript, PJL, PCL, status, pagecount support ### apple - PostScript printer, text to PS conversion, status, pagecount support ### postscript - PostScript printer, text to PS conversion, status, pagecount support ### ps - PostScript printer, text to PS conversion, status, pagecount support ### pcl - PCL only printer, no status ### pcl_gs - HP Laserjet 4 PCL only printer, write only, no status ### hpiiisi - HP LaserJet III (PCL and PostScript Interpreter)
Each printer type has an entry in the
Default Printer Magic Cookies # magic cookie definitions [default] # printer capabilities pjl # can do PJL pcl # can do PCL 5 ps # can do PS text # can do TEXT status # returns status by default sync # needs sync magic cookie sent ps_sync= serverdict begin 0 exitserver statusdict begin false setenginesync end # PostScript sync magic cookie definition # definition of available user options pjl_user_opts=[ ... simplex duplex ... ] # magic cookie strings for use when PJL, PostScript or PCL file pjl_duplex=@PJL SET DUPLEX = ON ps_duplex= statusdict begin true setduplexmode false settumble end pcl_duplex=\033&l1S
Each printer has a configuration section where the printer capabilities are defined, the user options that are available are specified, and the magic cookies that need to be sent to the printer to have the operations happen are defined. The
PostScript Only Printer a2ps_converter= /usr/local/bin/a2ps \%s{a2ps_options} a2ps_options= -q -B -1 -M \%M{papersize} --borders=no -o- gzip_decompress = /usr/bin/gzip -c -d # model for 'apple', 'postscript' or 'ps' [ apple postscript ps ] pjl@ pcl@ ps text@ file_output_match = [ *postscript* ps *text* ps \%s{a2ps_converter} *pdf* ps \%s{pdf2ps_converter} *gzip_compressed* filter \%s{gzip_decompress} ] # do { # $file = (lc ` file - `) =~ s/[\s\n]/_/gs; # foreach $line (@file_output_match) { # last if globmatch( $file, $line->[0] ); # } # if( $line->[2] ){ # run $file->[2] and convert input file to format # } # } while $line and $line->[1] != "filter" # outfile file format is $line->[1]
Here is an example of a PostScript only printer. The The
Using the &ifhp; Filter Printcap: lp:sd=/var/spool/lpd/%P :filter=/usr/local/lib/filters/ifhp :lp=/dev/lp # a PostScript printer that does not return status :ifhp= model=ps,status@
The
Example of &ifhp Operation h110: {205} % lpr /tmp/f.pdf h110: {205} % lpq -L Filter_status: using model 'DEFAULT' at 09:36:36.475 Filter_status: pagecount using 'pjl info pagecount' at 09:36:36.477 Filter_status: setting up printer at 09:36:36.477 Filter_status: getting sync using 'pjl echo' at 09:36:36.477 Filter_status: sync done at 09:36:38.335 Filter_status: pagecounter 105340 after 1 attempts at 09:36:38.349 Filter_status: pagecounter 105340 at 09:36:38.349 Filter_status: sending job file at 09:36:38.350 Filter_status: starting transfer at 09:36:38.350 Filter_status: file program = '/usr/bin/file -' at 09:36:38.350 Filter_status: started FILE_UTIL- 'file' at 09:36:38.351 Filter_status: file information = 'pdf_document,_version_1.2' at 09:36:38.415 Filter_status: initial job type 'pdf_document,_version_1.2' at 09:36:38.415 Filter_status: decoded job type 'POSTSCRIPT' at 09:36:38.415 Filter_status: job type 'POSTSCRIPT', converter '/usr/local/bin/pdf2ps - -' at 09:36:38.415 Filter_status: started CONVERTER- 'pdf2ps' at 09:36:38.416 Filter_status: converter done, output 707742 bytes at 09:36:39.589 Filter_status: transferring 707742 bytes at 09:36:39.590 Filter_status: 26 percent done at 09:36:40.338 Filter_status: 52 percent done at 09:36:41.082 Filter_status: 78 percent done at 09:36:41.830 Filter_status: data sent at 09:36:44.501 Filter_status: sent job file at 09:36:44.501 Filter_status: getting end using 'pjl job/eoj' at 09:36:44.501 Filter_status: end of job detected at 09:43:50.268 Filter_status: pagecounter 105359 after 1 attempts at 09:43:51.503 Filter_status: pagecounter 105359, pages 19 at 09:43:51.504 Filter_status: done at 09:43:51.504
As you can see the information produced by the &ifhp; filter is more than adequate for tracing its steps. You might want to try adding
Using -Z to Pass Options to &ifhp; h110: {227} % lpr -Zlandscape,duplex,copies=3 /tmp/hi Standard &ifhp; Options: Paper/Media Selection: a3, a4, a5, ledger, legal, letter envelope, oversize, transparency mediaselect=N Input Selection: inlower, inupper, manual Output Selection: outlower, outupper Copies: copies=N Orientation: landscape, portrait Duplex: duplex, duplexshort, simplex, lduplex, sduplex
Job formatting options are passed to
Testing &ifhp; Operations #!/bin/sh # sendhp.sh cp /dev/null /tmp/log cp /dev/null /tmp/out IP=10.0.0.14 ifhp=/usr/libexec/filters/ifhp # $ifhp -Tdev=$IP%9100,trace,debug=4 </tmp/one.ps 2>&1 | tee /tmp/log # $ifhp -Tdev=$IP%9100,trace,debug=1,appsocket,status,pagecount,waitend </tmp/one.ps 2>&1 | tee /tmp/log # $ifhp -Tdev=$IP%9100,trace,debug=1,pagecount_poll=2 </tmp/one.ps 2>&1 | tee /tmp/log $ifhp -Tdev=/tmp/out,trace,model=hp5 </tmp/one.ps 2>&1 | tee /tmp/log h110: {475} % sh /tmp/sendhp.sh ifhp 06:48:04.430 [3438] main: using model 'hp5' ifhp 06:48:04.433 [3438] Process_job: setting up printer ifhp 06:48:04.433 [3438] Do_accounting: pagecounter 0 ifhp 06:48:04.434 [3438] Process_job: sending job file ifhp 06:48:04.434 [3438] Send_job: starting transfer ifhp 06:48:04.434 [3438] Send_job: initial job type 'POSTSCRIPT' ifhp 06:48:04.434 [3438] Send_job: decoded job type 'POSTSCRIPT' ifhp 06:48:04.434 [3438] Send_job: job type 'POSTSCRIPT' ifhp 06:48:04.434 [3438] Send_job: transferring 145 bytes ifhp 06:48:04.434 [3438] Send_job: 100 percent done ifhp 06:48:04.434 [3438] Send_job: data sent ifhp 06:48:04.434 [3438] Process_job: sent job file ifhp 06:48:04.434 [3438] Do_accounting: pagecounter 0, pages 0 ifhp 06:48:04.434 [3438] Process_job: done h110: {475} % more /tmp/out ^[%-12345X@PJL @PJL RDYMSG DISPLAY = ":" @PJL USTATUSOFF @PJL USTATUS JOB = ON ...
You can test &ifhp; and see what it does by using the Taming the Wild Phaser Printer There are several printers that have network interfaces but which require very special treatment. Among these printers are the Tektronix Phaser/Appsocket Support Printcap: lp: :lp=/dev/null :filter=/.../ifhp :ifhp=model=phaser # OR :ifhp=appsocket,status,pagecount,waitend,dev=10.0.0.14%9100 Offline Test: IP=10.0.0.14 ifhp -Ttrace,debug=1,appsocket,status,pagecount,waitend,dev=10.0.0.14%9100 </tmp/one.ps 2>&1 | tee /tmp/log You need to specify the remote host and port to use to the Banner Pages and Accounting Banner pages are usually a waste of paper unless you need to make sure that user jobs are separated clearly. Even then, unless banner pages are on different stock or color they are usually ignored and thrown away. Suppressing Banner Pages Using the Incoming Control Filter Facility Most users do not
Changing JetDirect Configuration h110: {492} % telnet 10.0.0.14 Trying 10.0.0.14... Connected to h14.private. Escape character is '^]'. Please type [Return] two times, to initialize telnet configuration For HELP type "?" > ? ===JetDirect Telnet Configuration=== Configured Parameters IP Address : 10.0.0.14 Subnet Mask : 255.255.255.0 Default Gateway : 10.0.0.1 Syslog Server : 0.0.0.0 Idle Timeout : 121 Seconds Banner : 1 > banner: 0 > quit
Your first line of defense is to try to disable banner printing by the printer. This can be done (for HP Printers) as in . Note that the user name and password are not set by default so effectively anybody can modify your printer configuration.
Printcap Option <literal/:sh/ and &lpr; -h (No Header) Option Printcap: lp: ... :sh Command line: h110: {838} % lpr -h /tmp/hi No 'L' line in control file
The banner printing is triggered by the
Removing Banner Lines Printcap: lp:... :incoming_control_filter=/.../nobanner nobanner Script: #!/usr/bin/perl ... See # read stdin my( $file ); $file = join "", <STDIN>; $file =~ s/^L.*$/L/m; print $file; exit 0
The Forcing Banner Pages The
Forcing Banner Pages lp:... lp:server :ab # force a banner page on printing
Generating Banner Pages
Generating Banner Page lp: :of=/.../ifhp :bp=/.../banner.ps # for banner at start # :be=/.../banner.ps # for banner at end # :bs=/.../banner.ps # for banner at start &LPRng; banner generators: /usr/local/libexec/filters/psbanner - PostScript /usr/local/libexec/filters/pclbanner - PCL /usr/local/libexec/filters/lpbanner - Text
If you want to have a banner page printed you need to have two additional &lpd; facilities in the printcap entry: a banner printing program ( The banner printing programs are run exactly as a normal filter program, and the output is used as the banner to be printed. The &LPRng; If your printer requires special setup or conditioning, then you will have to specify a filter for the banner program. Historically this is done using the Accounting For a detailed discussion of accounting, please consult the &LPRng; HOWTO documentation. We will briefly cover some simple recipes for disaster here.
Basic Accounting Information lp: :af=acct # accounting file or :af=|/... # filter to run :af=host%port # remote server to query :as=jobstart $H $n $P $k $b $t # line to print :as=/... # filter to run at start of job :ae=jobend $H $n $P $k $b $t # line to print :ae=/... # filter to run at start of job :achk # check to see if allowed to print
The
Accounting File Information jobstart '-Hh110.private' '-npapowell' '-Pt1' '-kcfT456h110.private' '-b3' '-t2001-10-21-15:17:12.000' jobend '-Hh110.private' '-npapowell' '-Pt1' '-kcfT456h110.private' '-b3' '-t2001-10-21-15:17:
The accounting information provided by the &lpd; server is very basic and does not include page usage. However, we can have the print filters write information to the file as well. Filter Accounting Information jobstart '-Hh110.private' '-nroot' '-Plp' '-kcfA129h110.private' '-b48780' '-t2001-10-19-09:36:36.000' filestart '-q26132' '-p105340' '-t2001-10-19-09:36:38.350' '-Aroot@h110+129' '-nroot' '-Plp' fileend '-b19' '-T435' '-q26132' '-p105359' '-t2001-10-19-09:43:51.504' '-Aroot@h110+129' '-nroot' '-Plp' jobend '-Hh110.private' '-nroot' '-Plp' '-kcfA129h110.private' '-b48780' '-t2001-10-19-09:43:51.000' The Remember that &ifhp; can only get accurate page counting information if there is a physical page counter and it can be accurately read. This requires a bidirectional network link. Parallel ports The Accounting Gotchas
Accounting Gotchas jobstart '-Hh110.private' '-nroot' '-Plp' '-kcfA129h110.private' '-b48780' '-t2001-10-19-09:36:36.000' filestart '-q26132' '-p105340' '-t2001-10-19-09:36:38.350' '-Aroot@h110+129' '-nroot' '-Plp' jobstart '-Hh110.private' '-nroot' '-Plp' '-kcfA129h110.private' '-b49780' '-t2001-10-19-09:36:36.000' filestart '-q27992' '-p105340' '-t2001-10-19-09:36:38.350' '-Aroot@h110+129' '-nroot' '-Plp'
Observe the accounting file in . Clearly something has happened. The clever student (ummm... user?) has killed off the printer just as his last page has come out. There is no usage line. You will have to calculate usage based on the differences between the pagecounters at the start of each job. Of course, this can also be the result of a printer failure, bad print job, etc. etc. etc. Not to mention elves. Most student labs have lots of elves lurking in the background that cause endless headaches. Accounting Including Banner Pages
Accounting Using Banner Pages lp: :of=/.../ifhp :...
The Printer Pools and Load Sharing
Printer Pools and Load Sharing
A printer pool does load sharing amoung a group of printers. When you send a job to the main spool queue the job is then sent to the next available printer. If all of the printers are busy then the job is held in the queue .
Load Balancing Printcap main: :sd=/var/spool/lpd/%P:sv=sv1,sv2,sv3 sv1: :sd=/var/spool/lpd/%P:ss=main:lp=... sv2: :sd=/var/spool/lpd/%P:ss=main:lp=... sv3: :sd=/var/spool/lpd/%P:ss=main:lp=...
The printcap for setting up spooling is shown in . The
Load Balancing to Remote Queues
Printcap for Chooser main: # program to select destination :chooser=/.../chooser :destinations=s1@host1,s2@host2,s3@host3 # You can even combine the two forms # sv=...
The Implementing Smart Load Balancing
Chooser Program Operation # In Perlish @list = PC('destination'); # get destination list foreach $printer (@list) { if( PrinterAvailable( $printer ){ print $printer . "\n"; last; } }
The If you specify a
Filter Template in <application/Perl/ #!/usr/bin/perl use Getopt::Std; my $debug = 1; # always... sigh... my(%opt, @pc, %options); # get command line options getopts( 'A:B:C:D:E:F:G:H:I:J:K:L:M:N:O:P:Q:R:T:S:U:V:W:X:Y:Z:' . 'a:b:cd:e:f:g:h:i:j:k:l:m:n:o:p:q:r:t:s:u:v:w:x:y:z:', \%opt ); while( @ARGV ){ $opt{acct} = pop @ARGV ; }; # split up the PRINTCAP_ENTRY environment variable value @pc = split /\n\s*:/s, ($ENV{PRINTCAP_ENTRY} || ""); shift @pc; # throw way first entry field, printer name # set the options foreach (@pc){ # set the options values if( /^(.+)=(.*)/ ){ $options{$1} = $2; } elsif ( /^(.+)@/ ){ $options{$1} = 0; } else { $options{$_} = 1; } } if( $debug ){ # for those interested my $s = ""; foreach my $v (sort keys %options ){ $s .= "$v='$options{$v}',"; } print STDERR "Printcap: '$s'\n"; $s=""; foreach my $v (sort keys %opt){ $s .= "$v='$opt{$v}',"; } print STDERR "Args: '$s'\n"; }
This is the standard filter template. We use this almost everywhere.
Choosing A Destintation my (@list, @destinations); if( $options{sv} ){ # if we have :sv then we read them from STDIN while( <STDIN> ){ chomp; push @destinations, $_; } } else { # else we use the 'destinations' printcap value @list = split /[,\s]+/, ($options{destinations} || ""); # and we randomize - this is a bit of perl magic while( @list ){ push @destinations,(splice @list,rand(@list),1); } } # and we split the destinations up... print STDERR "Destinations '@destinations'\n" if $debug; # and now we search my $lpq="/usr/bin/lpq"; foreach ( @destinations ){ my $status = ""; next if not $_; # run the lpq eval { alarm(10); $status = `$lpq -s -P$_`; }; alarm(0); chomp $status; print STDERR "STATUS '$_' $status\n" if $debug;; # we reject queues that are not suitable next if( $status =~ /disabled/ or $status != / 0 jobs / ); print STDERR "chose '$_' from @$destinations\n"; print $_; last; }
We first get the list of destinations - from If no printer is available then nothing is printed on Normally, only the first job in the spool queue is checked to see if it can be printed. However, by setting the Using <literal/:chooser/ Exit Codes
Chooser Exit Codes Exit Code Action 0 (JSUCC) Use chooser output for destination (No destination, retry later) 1 (JFAIL) Failed - retry later (same as JSUCC, no destination) 2 (JABORT) Abort printing, wait for restart 3 (JREMOVE) Remove job 4 (JHOLD) Set job HOLD flag
The Wildcards, Bounce Queues, and Forwarding One of the things you might want to do is have a set of queues that massage the various jobs and then send them to a destination printer.
Evil (BAD) Way landscape:force_localhost :ifhp=model=xx :filter=/.../convert_to_landscape | /.../ifhp :lp=10.0.0.14%9100 portrait:force_localhost :ifhp=model=xx :filter=/.../convert_to_landscape | /.../ifhp :lp=10.0.0.14%9100 lp:tc=.common :ifhp=model=xx :filter=/.../ifhp :lp=10.0.0.14%9100
Each queue will now fight for a connection to the destination printer. Bounce Queues
Not So Evil Way landscape:tc=.common :filter=/.../convert_to_landscape :lp=lp@localhost portrait:tc=.common :filter=/.../convert_to_landscape :lp=lp@localhost lp:tc=.common :ifhp=model=xx :filter=/.../ifhp :lp=10.0.0.14%9100
You have various filters set up so that each queue does a conversion and then forwards it to the real printer for output. No fighting. This method is called Adding -Z Options Using Bounce Queues
Add Options Using <literal/:append_z/ landscape:tc=.common :append_z=landscape :lp=lp@localhost portrait:tc=.common :append_z=portrait :lp=lp@localhost # ifhp (or other) filter uses the -Z options lp:tc=.common :ifhp=model=xx :filter=/.../ifhp :lp=10.0.0.14%9100
Now you can add one option at a time. But what if you want to do landscape and duplex mode at the same time? You need to create a Adding Options By Using The Incoming Control Filter Facility
Option Modification .common=force_localhost:sd=/var/spool/lpd/%P:sh:mx=0 lp|lp_* # we recognize lp_xxxx for this filter :tc=.common :incoming_control_filter=/.../update_z :ifhp=model=xx :filter=/.../ifhp :lp=10.0.0.14%9100 -- for landscape: h110: {838} % lpr -Plp_landscape -> Control file: Zlandscape -- for portrait h110: {838} % lpr -Plp_portrait -> Control file: Zlandscape -- for landscape and duplex h110: {838} % lpr -Plp_landscape_duplex -Zother -> Control file: Zother,landscape,duplex
If you use a
Incoming Control Filter filter input: job control or job ticket Xoldvalue X=oldvalue filter output: X <- delete X option X= <- delete X option Xvalue <- set option X value X=xxx <- alternative set option X value
When the job arrives its options can be modified by using the The The . All of the standard control file options start with upper case letters followed immediately by either the option value or an equals sign. Other options start with lower case letters and have a The Form Support and Hold Queues Sometimes jobs require a special setup on a printer, and jobs cannot be printed unless it is done. There are several ways to handle this. Hold Queues
Hold Queues .common=force_localhost:sd=/var/spool/lpd/%P:sh:mx=0 setup1:tc=.common :ah # always hold incoming jobs :lp=lp@localhost setup2:tc=.common :ah # always hold incoming jobs :lp=lp@localhost lp:tc=.common # print queue :ifhp=model=xx :filter=/.../ifhp :lp=10.0.0.14%9100
All Hold Queues h110: {853} % lpq -Psetup1 Printer: setup1@h110 (dest t1@localhost) (autohold) Queue: no printable jobs in queue Printer: t1@h110 'Test Printer 1' (printing disabled) Queue: no printable jobs in queue h110: {854} % lpr -Psetup1 /tmp/hi h110: {855} % lpq -Psetup1 Printer: setup1@h110 (dest t1@localhost) (autohold) Queue: no printable jobs in queue Holding: 1 held jobs in queue Server: no server active Rank Owner/ID Class Job Files Size Time hold papowell@h110+356 A 356 /tmp/hi 3 15:02:50 Printer: t1@h110 'Test Printer 1' (printing disabled) Queue: no printable jobs in queue
When we print jobs to a
Releasing Jobs for Printing h110: {856} % lpc release setup1 all Printer: setup1@h110 setup1: selected 'papowell@h110+356' setup1@h110.private: started h110: {857} % lpq -Psetup1 Printer: setup1@h110 (dest t1@localhost) (autohold) Queue: no printable jobs in queue Status: job 'cfA356h110.private' removed at 15:03:49.053 Printer: t1@h110 'Test Printer 1' (printing disabled) Queue: 1 printable job Server: no server active Rank Owner/ID Class Job Files Size Time 1 papowell@h110+356 A 356 /tmp/hi 3 15:03:49 h110: {858} %
We can release the jobs which are then forwarded to the main queue for printing. We can also set up
Releasing Jobs For Scheduled Print Run Printcap: nightrun: :ah # always hold incoming jobs :lp=lp@localhost Crontab Entry To Release Jobs: #minute hour mday month wday who command 1 3 * * * root /usr/sbin/lpc release nightrun all
You can also use the &LPRng;
Using Job Classes h110: {870} % lpc class t1 top,middle Printer: t1@h110 classes printed 'top,middle' t1@h110.private: class updated h110: {871} % lpq Printer: t1@h110 'Test Printer 1' (classes top,middle) Queue: no printable jobs in queue h110: {872} % lpr -Clow /tmp/a h110: {873} % lpq Printer: t1@h110 'Test Printer 1' (classes top,middle) Queue: no printable jobs in queue Holding: 1 held jobs in queue Server: no server active Rank Owner/ID Class Job Files Size Time holdclass papowell@h110+451 L 451 /tmp/a 38404 15:16:39 h110: {874} % lpr -Ctop /tmp/hi h110: {875} % lpq Printer: t1@h110 'Test Printer 1' (classes top,middle) Queue: no printable jobs in queue Holding: 1 held jobs in queue Server: no server active Status: job 'cfT456h110.private' removed at 15:17:12.932 Rank Owner/ID Class Job Files Size Time holdclass papowell@h110+451 L 451 /tmp/a 38404 15:16:39
You can specify a current list of classes to be printed using the &lpc; . the jobs not in the current classes are held until explicitly released or until the class is changed. You can disable the job class facility by setting the class to
Setting New Job Classes and Disabling Job Classes h110: {877} % lpc class t1 low Printer: t1@h110 classes printed 'low' t1@h110.private: class updated h110: {879} % lpq -ll Printer: t1@h110 'Test Printer 1' (classes low) Queue: no printable jobs in queue Status: finished 'papowell@h110+451', status 'JSUCC' at 15:22:03.178 Status: subserver pid 84477 exit status 'JSUCC' at 15:22:03.179 Status: t1@h110.private: job 'cfL451h110.private' printed at 15:22:03.180 Status: job 'cfL451h110.private' removed at 15:22:03.181 h110: {39} % lpc class t1 off Printer: t1@h110 all classes printed t1@h110.private: class updated h110: {40} % lpq Printer: t1@h110 'Test Printer 1' Queue: no printable jobs in queue Status: job 'cfL451h110.private' removed at 15:22:03.181
You can also put a class value into the control file using the .
Modifying Control File Using <application/update_class/ lp|lp_*:tc=.common :incoming_control_filter=/.../update_class :ifhp=model=xx :filter=/.../ifhp :lp=10.0.0.14%9100
The
The <application/update_class/ Filter #!/usr/bin/perl ... See # read stdin my( $file, $Copts, $Q ); $file = join "", <STDIN>; print STDERR "File '$file'\n" if $debug; # first use command line Queue name, then control file Q # then the printer name, then control file P $Q = $opt{Q}; ($Q) = $file =~ /^Q(.*)$/m if not $Q; # if no queue name fall back to printer name $Q = $opt{P} if not $Q; ($Q) = $file =~ /^P(.*)$/m if not $Q; $Q = "" if not $Q; # stupid -w... sigh... # get Copts ($Copts) = $file =~ /^C(.*)$/m; $Copts = "" if not $Copts; # stupid -w ... sigh ... print STDERR "Q '$Q', Copts '$Copts'\n" if $debug; # now we split up the name and use as parameters for C option while( $Q =~ /_([^_]+)/g ){ $Copts = $1; } print "Final '$Copts'\n" if $debug; if( $Copts ){ $file = "C$Copts\n" . $file if( not ($file =~ s/^C.*$/C$Copts/m)); } print $file; exit 0
Interfacing to Vintage, Legacy, and SunOS Print Spoolers Some legacy, vintage, and other print spoolers do not meet the RFC1179 requirements, or accept only control files with options used by the original BSD (1984 vintage) print spooler and only in the order used by the original BSD (1984 vintage) print spooler. The
Using <literal/:bk/ (Berkeley Kompatible) Flag lp:force_localhost@ # make control files berkeley :bk :lp=...
Managing Enterprise Level Printing Systems If you are doing management of more than 20 printers, then you already know the headaches. You need to make the printers available to all/some/none of your users, each user has a different set of requirements, and no two printers are the same. The following are some helpful suggestions and recipes for managing printer information. Templates and Standard Configurations
Templates in Printcaps .common :sh:sd=/var/spool/lpd/%P:force_localhost .hplj4 :ifhp=model=hp4 :filter=/.../ifhp # server information hp4:server:tc=.common,.hplj4 :lp=10.0.0.14%9100 #client information hp4:client:lp=%P@server1
You should set up a standard set of templates to see what you have. You can then use &lpc; to see what the printcap is.
Using &lpc; client all .defaults :ab@ ... .config .all :t1 :t2 #Printcap Information t1|t1_* :filter=/usr/local/libexec/filters/ifhp :lp=/var/tmp/t1_lp :sd=/var/spool/lpd/%P t2|Test Printer 2 :lf=log :lp=t1@h110.private :sd=/var/spool/lpd/%P
You can use Master Print Servers, One User Printcap
Master User Printcap File, No Local Spooling # Just information for clients # list all of the printers for this server lp1|lp2|..... :client:lp=%Q@server1.private:force_localhost@ lp99|.... :client:lp=%Q@server2.private:force_localhost@
This will allow you to send jobs directly to the print server. You use the Master Print Servers, Local Spooling
Master User Printcap File, Local Spooling # Just information for clients # list all of the printers for this server lp1|lp2|..... :client:lp=%Q@server1.private:force_localhost lp99|.... :client:lp=%Q@server2.private:force_localhost
Observe that you have two queues, one per print server. You use the Master Print Servers, Selection by User
Master User Printcap File, No Local Spooling # list all of the printers for this server lp1|lp2|..... OR lp1|* :client:lp=%Q@server1.private:force_localhost@ :oh=*.engineering.private lp1|lp2|..... OR lp1|* :client:lp=%Q@server2.private:force_localhost@ :oh=*.marketing.private
You can use the 10.0.0.0/24 or 10.0.0.0/255.255.255.0) or a wildcard match for the DNS resovled host name ( The Great Grand Dad Of All Printcap Files
All In One # list all of the printers for this server lp1|lp2|..... :client:lp=%Q@server1.private:force_localhost@ :oh=*.engineering.private lp1|lp2|..... :client:lp=%Q@server2.private:force_localhost@ :oh=*.marketing.private lp1:server :.... lp2:server :....
Add all the printer information in as well. Huge printcap files. But very easy to manage. But how do you get them to the user? Using Printcap Filters and Central Databases
Printcap Path Configuration Information /etc/lpd.conf: # Purpose: lpd printcap path # default lpd_printcap_path= (STRING) # Purpose: /etc/printcap files # default printcap_path= /etc/printcap (STRING) printcap_path=|/usr/local/libexec/get_printcap
If the &conf;
Example of Returned Printcap Value Configuration: printcap_path = |/usr/local/bin/get_ldap_pc h110: {917} % lpr -Plp Printcap access equivalent to Perlish: $printcap = `echo lp | /usr/local/bin/get_ldap_pc` Configuration: lpd_printcap_path = |/usr/local/bin/get_lpd_ldap_pc lpd server will do: $printcap = `echo lp | /usr/local/bin/get_lpd_ldap_pc`
The exercise of building the necessary &LPRngTool;
Starting Screen
Printcap Entry Selection
Add A Printer
Option Specification
Advanced Options
&ifhp Options
Saving Printcap Entry
Checkpc Results
&LPRng; The &LPRng; print spooler software was developed to be robust, reliable, secure, scalable, and portable. It has been used since 1988 in extremely demanding academic printing environments such as University of Minnesota, MIT, and Rutgers, commercial companies such as Dow Jones and Abbot Pharmaceuticals, as well as being distributed with Linux, FreeBSD, and other systems. Each of these environments has a unique set of problems, demanding various configuration and administrative capabilities. For example, the simple single user system with a single or limited number of printers requires easy configuration and simple diagnostic procedures, while the network based printing system requires highly robust error logging, authentication, and failover support. &LPRng; provides a highly flexible configuration system that allows it to perform optimally in all of these environments. The &LPRng; software has three components: the &lpd; print spooler and the user client applications &LPRng; mimics many of the features of the vintage or legacy Berkeley (University of California - Berkeley) Line Printer (LPR) package found on Berkeley derivatives of the Unix operating system. &LPRng; will print a document with little or no knowledge of the content or special processing required to print the document on a stand-alone machine or in a distributed printing environment. New (as compared to Berkeley LPR) features include: lightweight lpr, lpc and lprm programs, dynamic redirection of print queues, automatic job holding, highly verbose diagnostics, load balancing queues; enhanced security (SUID not required in most environments), and easy configuration. &LPRng; started life at the University of Waterloo in 1986 as PLP (Public Line Printer), a replacement for the original BSD jmason@iona.ie) who started the &LPRng; mailing list. In 1992 while at San Diego State University Prof. Powell redesigned and reimplemented the PLP code and named the result &LPRng;. The goals of the &LPRng; project were to build a server system that was as close to user abuse proof as possible, that would provide services limited only by the inherent capacities of the support system, RFC1179 compliant, and with extensive debugging capabilities to allow quick and easy diagnostics of problems. In 1999 the code base for &LPRng; was again reorganized in order to provide a common method for running on non-UNIX platforms such as Microsoft Windows NT, Apple Rhapsody, and embedded systems. As a side effect of this work, many security problems that could develop were identified and steps taken to ensure that they were not present in &LPRng;. For example, &LPRng; clients such as lpr, lprm, lpc, and lpq can run as ordinary users programs, the lpd server can run as a non-root user once a network port has been opened, and all text formatting operations done by &LPRng; use a very restricted and highly secure version of the Documentation The main &LPRng; documentation is the LPRng-HOWTO, which is available in several formats. Information about &LPRng; and the latest release can be found on the &LPRng; web page http://www.lprng.com/LPRng.html The &ifhp; documentation is the IFHP-HOWTO, which is available in the &ifhp; distribution. Information about &ifhp; and the latest release can be found on the &LPRng; web page http://www.lprng.com/LPRng.html There is also a mailing list at lprng@lprng.com. To post to the list you must subscribe by sending send an email to lprng-request@lprng.com, with the message subject or body containing the word `subscribe' or `help'. Several presentations of &LPRng; and print spooling software have been made at the Large Installation System Administrator (LISA) conferences. The presentation at the LISA 98 conference is in the PowerPoint file LISA98.ppt in the &LPRng; distribution documentation. Installation It is recommended that installation be done from the source distribution, and that the files be put in the /usr/bin, /usr/sbin, and /etc directories, as most existing applications require them there. Get the source code distribution from the main &LPRng; site or one of the mirror sites show in . The install using: %> gunzip -c LPRng-XXX.tgz | tar xvf - %> cd LPRng-XXX ./configure --prefix=/usr --sysconfdir=/etc #if your OS does not support shared libraries, use: # ./configure --disable-shared --prefix=/usr --sysconfdir=/etc %> make clean all %> su password: xxxxx #> make install License The &LPRng; Print Spooler and the ifhp Print Filter software are distributed under the GNU Public License (GPL) and the Artistic License. Users can choose to redistribute or use the software under a license that is appropriate for their purpose. Other licenses and distribution agreements are available by contacting AStArt Technologies for information. Commercial Support AStArt Technologies provides commercial support and enhancements for the &LPRng; and other network software. AStArt provides network and system consulting services for UNIX and NT systems, as well as real time and network software. Web Site, FTP Site, and Mirrors Web Page: http://www.lprng.com Main FTP Site: ftp://ftp.lprng.com/pub/LPRng (US) Mirrors: ftp://ftp.cs.columbia.edu/pub/archives/pkg/LPRng (US) ftp://ftp.cise.ufl.edu/pub/mirrors/LPRng (US) ftp://ftp.cs.umn.edu/pub/LPRng (US) ftp://uiarchive.uiuc.edu/pub/packages/LPRng (US) ftp://ftp.sage-au.org.au/pub/printing/spooler/lprng/ (AU) ftp://mirror.aarnet.edu.au/pub/LPRng/ (AU/NZ) http://mirror.aarnet.edu.au/pub/LPRng/ (AU/NZ) ftp://sunsite.ualberta.ca/pub/Mirror/LPRng (CA) ftp://ftp.informatik.uni-hamburg.de/pub/os/unix/utils/LPRng (DE) ftp://ftp.uni-paderborn.de/pub/unix/printer/LPRng (DE) ftp://ftp.mono.org/pub/LPRng (UK) ftp://ftp.iona.com/pub/plp/LPRng (IE) ftp://uabgate.uab.ericsson.se/pub/unix/LPRng (SE) Mailing List To join the &LPRng; mailing list, please send mail to lprng-request@lprng.com with the word 'subscribe' in the BODY. The &LPRng; mailing list is archived on http://www.findmail.com/list/lprng PGP Public Key The &LPRng; distributions have an MD5 checksum calculated, which is then signed with a PGP public key. Here is the key for validating the checksums: Type Bits/KeyID Date User ID pub 1024/00D95C9D 1997/01/31 Patrick A. Powell \ <papowell@lprng.com> -----BEGIN PGP PUBLIC KEY BLOCK----- Version: 2.6.3i mQCNAzLygTQAAAEEANBW5fPYjN3wSAnP9xWOUc3CvsMUxjip0cN2sY5qrdoJyIhn qbAspBopR+tGQfyp5T7C21yfWRRnfXmoJ3FVtgToAsJUYmzoSFY08eDx+rmSqCLe rdJjX8aG8jVXpGipEo9U4QsUK+OKzx3/y/OaK4cizoWqKvy1l4lEzDsA2VydAAUT tCdQYXRyaWNrIEEuIFBvd2VsbCA8cGFwb3dlbGxAYXN0YXJ0LmNvbT6JAJUDBRA0 XonoiUTMOwDZXJ0BAQ2cBAC7zU9Fn3sC3x0USJ+3vjhg/qA+Gjb5Fi1dJd4solc4 vJvtf0UL/1/rGipbR+A0XHpHzJUMP9ZfJzKZjaK/d0ZBNlS3i+JnypypeQiAqo9t FV0OyUCwDfWybgAORuAa2V6UJnAhvj/7TpxMmCApolaIb4yFyKunHa8aBxN+17Ro rrQlUGF0cmljayBBLiBQb3dlbGwgPHBhcG93ZWxsQHNkc3UuZWR1PokAlQMFEDLy gTSJRMw7ANlcnQEBYBYD/0zTeoiDNnI+NjaIei6+6z6oakqO70qFVx0FG3aP3kRH WlDhdtFaAuaMRh+RItHfFfcHhw5K7jiJdgKiTgGfj5Vt3OdHYkeeh/sddqgf9YnS tpj0u5NfrotPTUw39n6YTgS5/aW0PQfO9dx7jVUcGeod1TGXTe9mIhDMwDJI4J14 =3Zbp -----END PGP PUBLIC KEY BLOCK----- References and Standards The following references and standards have been used in the development of the &LPRng; software. RFCs During the early development of the Internet developers did not want to go through the laborious process of developing formal standards and applying to a standards body such as the EIA, IEEE, or ISO. Instead, they called the standards documents they developed Requests for Comments. These soon became de facto standards, and with the formal acceptance of the TCP/IP protocol as a network standard, de jure as well. You can get copies of the RFCs from literally hundreds of network sites, including http://www.isi.edu, http://www.faqs.org/rfcs, NIS.NSF.NET, RFC.JVNC.NET, or FTP.ISI.EDU. The RFC1179 - Line Printer Daemon Protocol describes the protocol used to transfer jobs from client program to print server. See RFC1179 for more a discussion of this protocol and more details about the RFC. The rfc1179.txt file is included in the &LPRng; distribution documentation. PostScript PostScript is one of the de facto standards for print jobs. The Adobe Corporation (http://www.adobe.com) provides an excellent set of references for the PostScript language. They have made many of these available for downloading from their web sites or have published them in book form. The PostScript Language Reference Manual contains a great deal of technical information about the PostScript Language, and is the language reference manual. The PostScript Language Tutorial and Cookbook is a very nice and easy to read introduction to PostScript programming, and has some very useful utilities. Combined with The PostScript Language Program Design is the companion to the PostScript Language Tutorial and Cookbook, and has more complex examples of PostScript programs. More importantly, it also introduces, although without explanation, the PostScript Document Structuring Conventions described in Appendix G of the The PostScript Language Reference Manual. This alone makes it useful. HP PCL 5 The Hewlett-Packard (HP) PCL Printer Language is the second de-facto standard for print jobs. Currently, Hewlett-Packard makes documentation for PCL available through their Developer Program. You will need to register and then search their site for the PCL 5 Printer Language Reference Manual. HP PJL The Hewlett-Packard (HP) Printer Job Language is used to control various features of HP printers. The Printer Job Language Reference Manual is also available from Hewlett-Packard (http://www.hp.com) through their Developer Program. PDF The Portable Document Format (pdf) was developed by Adobe to be a more useful method of distributing documentation for view by online systems and software. The Portable Document Format Reference Manual is available from Adobe (http://www.adobe.com). While pdf is not used directly as a print job language, it is one of the more common formats for files that need to be printed. It can be converted to PostScript by most pdf viewers such as GhostScript and Adobe Acrobat. RFC 1179 - Line Printer Daemon Protocol RFC1179 can be obtained from the &LPRng; distribution, in the LPRng_DOC/rfc1179 directory, or from one of many sites which mirror the RFCs. This RFC is an informational RFC, which means that the information in it is meant as a guide to users, and not as a fixed standard. In addition, the RFC tried to document the behavior of the BSD In this section, I will try to explain what RFC1179 specifies as a protocol, and many of the problems encountered in trying to use it. Ports and Connections Options used: lpd_port=Port for originate_port=Ports to originate connections on reuse_addr FLAG Set SO_REUSEADDR flag on connection retry_econnrefused FLAG Retry on connect ECONNREFUSED error retry_nolink FLAG Retry on device open or connection ffailure socket_linger=socket linger timeout RFC1179 requires that the lpd server listen for TCP/IP connections on port 515. This port is registered with the Internet Naming Authority, and the /etc/services file or TCP/IP services database usually has an entry: printer 515/tcp spooler # line printer spooler RFC1179 explicitly states that all connections to port 515 must originate from ports 721-731. The reason for this restriction is due to the UNIX concept of reserved and privileged ports. By convention, ports in the range 1-1023 can only bound by processes whose Effective User ID (EUID) is 0 (root). This, ordinary users could not originate a connection from the reserved or privileged port range. In a UNIX environment, this means that the user programs lpr, lpq, lprm, and lpc would have to be SETUID root. As experience has shown, for security purposes, the fewer programs that need to have privileged status, the better. &LPRng; uses the lpd_port=printer configuration option to set the actual port to be use. By default, this is port 515, but can be set to other values. The restriction of originating ports to 721-731 causes another set of problems. Part of the TCP/IP protocol is concerned with avoiding communications problems resulting from the arrival of old or stale packets. When a connection between sourcehost, sourceport and desthost, destport is made, a set of sequence numbers is established and used for sending and acknowledgement of data. When the connection terminates, the TCP/IP protocol restricts the establishment of a new connection between sourcehost, sourceport and desthost, destport for a period long enough for all stale packets to be removed from the system. This is approximately 10 minutes long. In order to simplify assignments of ports, timing out connections, and other matters, many TCP/IP packages do keep track of explicit connections originating from a port, but simply prevent the port from being reused for either origination or reception of a connection. They do, however, keep track of the active connections to a port, and perform timeouts on these. This is usually much simpler to implement, as it can be done with a list attached to the port. This implementation method creates some problems when a large number of connections must be originated from a relatively small number of port numbers. Observe what happens when host 1 tries to send a large number of jobs to a server 2. The following connections are established and terminated: host 1, port 721 and host 2, port 515 host 1, port 722 and host 2, port 515 host 1, port 723 and host 2, port 515 host 1, port 724 and host 2, port 515 host 1, port 725 and host 2, port 515 host 1, port 726 and host 2, port 515 host 1, port 727 and host 2, port 515 host 1, port 728 and host 2, port 515 host 1, port 729 and host 2, port 515 host 1, port 730 and host 2, port 515 host 1, port 731 and host 2, port 515 Now according to the RFC1179 rules and the TCP/IP protocol, we will have to wait until one of these connections terminates before we can make another. On the originating system, if the TCP/IP implementation does timeouts on the originating port, we will have to wait for the timeout to elapse before we can make a new connection. Unfortunately, there is no way to find out what the status of the port is, so we will have to try them each in turn until we get a successful connection. The &LPRng; code has tried to provide several methods to deal with these problems. Firstly, the originate_port=512 1023 option specifies the range of ports used to originate connections when the software is running either as ROOT or SETUID root. By strict RFC1179 rules, this should be originate_port=721 731, but it turns out that most BSD reserved originating port. By using 512 ports we get a greatly reduced rate of errors due to lack of ports due to pending timeouts. However, on some systems which are acting as servers for a large number of printers even increasing this port range is insufficient, and steps need to be taken use the originating port numbers more efficiently. The Berkeley TCP/IP implementation getsockopt() and setsockopt() allows the user to manipulate some of the underlying timeouts and options of the TCP/IP network. When a TCP/IP connection is established, the setsockopt() facility can be used to set the SO_REUSEADDR flag on the connection. This flag effectively sets the timeout value on the ports and connections to 0, allowing immediate reuse of the ports. When done on an originating end of a connection, this will allow the originating port number to be reused immediately. It would appear that by setting SO_REUSEADDR on the originating end that we have solved our problems. However, unless the destination end of the connection sets its SO_REUSEADDR flag on the connection, it will still do a timeout. Thus when we try to make a connection from a port that was active within a short period of time to the same host, then it will reject the connection until the timeout is over. The reuse_addr flag (default off) forces the &LPRng; software to set the SO_REUSEADDR flag on originating connections. As indicated, this will allow ports to be reused immediately for outgoing connections, rather than waiting for a timeout. While the reuse_addr flag usually allows us to reuse ports, there is still the problem of dealing with connections failing due to the remote site rejecting the connection due to a pending timeout from a previous connection. A careful study of the original BSD TCP/IP network code and of some others indicates that when a connection fails due to a pending timeout, an ECONNREFUSED error code is returned to a connect() system call. If this happens and we suspect that the remote site is rejecting the connection due to a timeout problem, then we should retry making the connection but from a new port, and continue retrying until all possible ports are used. The retry_econnrefused (default on) flag is used to specify that we retry connections in this manner. When this is set, a connection refused error causes the connection to be retried using a new port. This will be repeated until all available ports have been tried. When printing a job and the lpd server connection to a remote site or device open fails, the retry_nolink (default on) will cause the attempt to be retried indefinitely. The combination of retry_econnrefused and retry_nolink will provide robust connection attempts to remote systems. While the above problems cause difficulties when making connections, there are also problems when terminating connections. After closing a socket, the TCP/IP software will try to flush any pending data to the destination. Unfortunately, on some systems it will only do this while the process is active. This has caused problems on systems which terminate a process it has received an abnormal (signal caused) termination. The setsockopt() SO_LINGER option allows the user to specify that when a socket is closed normally, that the process should block until pending data is flushed or for the socket_linger period. If socket_linger is 0, then no SO_LINGER operation is done. In summary, if you experience problems with connection failures due to port exhaustion, first try setting the reuse_port flag, and you should see a reduction. Check to ensure that the retry_econnrefused and retry_nolink flags are set, and the error code in the log and status files. If the failures continue, then the problem is caused by the remote end having timeout limitations and there is little you can do except to set a very long connect_retry interval, say connect_retry=120 (2 minutes). Protocol Requests and Replies Options used: remote_support=Remote operations supported After a connection has been established, a request can be sent to the lpd server. The request consists of a single octet indicating the request type, followed by the printer (or print queue) name, followed by a set of options for the request, followed by a LF (line feed) character. RFC1179 Commands NNNRFC1179Operationprogram1yesstart printlpc2yestransfer a printer joblpr3yesprint short form of queue statuslpr4yesprint long form of queue statuslpr5yesremove jobslprm6&LPRng;do control operationlpc7&LPRng;transfer a block format print joblpr8&LPRng;secure command transferlpc9&LPRng;verbose status informationlpr
After the request has been sent, then a reply will be returned. In general the reply has the following form: \000\n Success \NNN\n Failure (NNN is error code) text\n Text or status information As can be seen, this protocol is extremely simple, but there are a set of problems due to the loosely written language of RFC1179. Firstly, while RFC1179 sets limits on the lengths of commands, it does not strictly set limits on the characters set used in the commands. This can result in problems when trying to print status information, headers on banners, and other details. The original RFC1179 protocol did not provide any way to do remote control of queues or lpc to control a non-&LPRng; printer, it will not work. You can specify that a network printer is non-&LPRng; by using the remote_support=RQVMC option and specify the operations supported by the printer. The letters R, Q, M, and C stand for lpr, lpq, lprm, and lpc operations respectively, and indicate that these are supported. If remote_support does not allow a particular operation, then the &LPRng; software will not send a corresponding request to the printer. For example, remote_support=R would restrict operations to spooling jobs only, and the &LPRng; software would not query the printer for status. Job Transfer Options used: longnumber FLAG Long job number (6 digits) send_data_first FLAG Send data files first use_shorthostUse short hostname A job transfer operation starts with a job transfer request, followed by several file transfer operations. At the end of the file transfers, the connection should be closed. A file transfer request has the form: CommandPurpose \001\nabort \002nnnn cfnamecontrol file transfer \003nnnn dfnamedata file transfer The abort operation is used to terminate job transfer and indicate that the job should not be processed for printing. The connection will be closed and the partly transferred job will be discarded. The control file and data file transfer commands have a length (in bytes) of the file and the name of the file to be transferred. When the command is received, the server will reply with a status line: StatusPurpose \000Accepted, proceed \nnnRejected with error code The reply is only a single octet. Some defective implementations of RFC1179 send a LF after the octet, which makes life very difficult. &LPRng; makes an effort to detect these non-conforming RFC1179 systems and will accept jobs from them. However, it will not send jobs to them. If &LPRng; sends a reject code, as an extension to RFC1179 it also sends an error message. Note that the values for error codes are not defined, nor are their causes. &LPRng; uses the following values for error codes, which appear to be compatible with many, but not all, of the BSD CodeError \000Accepted, proceed \001Queue not accepting jobs \002Queue temporarily full, retry later \003Bad job format, do not retry When the sender gets the reply indicating success, it sends the nnnn bytes of the control or data file, followed by a \000 octet. The receiver will then reply as above; a single \000 octet indicating success. The above procedure is carried out until all data files and the control file of a job are transferred. RFC1179 is silent on the following issues: When sending a job, do you send the control file first, followed by the data file(s), or the data files first? When sending multiple jobs, can you send them on a single connection, or do you have to establish a new connection for each job? &LPRng; will accept jobs whether they are sent control or data files first. By default, it sends the control file first, followed by the data file. If the destination system requires that the data files be sent first, the send_data_first printcap option can be used to force data files to be sent first. RFC1179 states that:
The name of the control file ... should start with ASCII "cfA", followed by a three digit job number, followed by the host name which has constructed the control file.
The should in this wording indicates that this is simply a guideline, and that other formats are possible. Some of the major problems with this format are as follows: The restriction to 3 digits means that at most 1000 jobs can be in a queue. Strangely, some systems generate far more than 1000 jobs a day, and need to archive them on a regular basis. The longnumber option will allow &LPRng; to use a 6 digit job number for files in the print queue. The host name format is not specified. Some implementations consider that this is the short host name, while others think it is the fully qualified domain name (FQDN). &LPRng;, by default, will use the FQDN host name. However, the use_shorthost option will force it to use short host names in control and data files. The cfA control file name was modified to allow the job priority to be used as the A letter of the control file. By default, this is A (lowest, i.e. cfA) and but can range to Z (highest, i.e. cfZ). All known spoolers except &LPRng; seem to ignore the actual value of the letter. Data File Transfer As mentioned before a data file is transferred using the command below. CommandPurpose \003nnnn dfnamedata file transfer From RFC1179:
The data file may contain any 8 bit values at all. The total number of bytes in the stream may be sent as the first operand, otherwise the field should be cleared to 0. The name of the data file should start with ASCII "dfA". This should be followed by a three digit job number. The job number should be followed by the host name which has constructed the data file. Interpretation of the contents of the data file is determined by the contents of the corresponding control file.
There are several surprises in RFC1179. Apparently a job should only consist of a single data file. This is a severe limitation, and in fact the BSD dfA, dfB, ... dfZ, dfa, dfz. The RFC does not specify that the control file and data file job numbers must be identical. Most implementations follow this convention, which simplifies life tremendously. The RFC does not specify that the control file and data file job host names must be identical. Most implementations follow this convention, which simplifies life tremendously. A zero length data file does not cause a data transfer to take place. &LPRng; modifies this action to be slightly different. When a zero length data file transfer is indicated, all of the input until the connection is closed is used as the contents of the data file. When lpr program, this can be very useful as it eliminates the need to create temporary files on the local host. Note that some print spoolers do not use this interpretation, and this option should be used carefully. Control File Contents The control file consists of a set of lines which either provide printing information or specify data files to be printed. The information lines start with upper case letters or digits, while the data files lines start with lower case letters. Here is a sample control file: Hh4.private J(stdin) CA Lpapowell Apapowell@h4+955 Ppapowell fdfA955h4.private N(stdin) UdfA955h4.private The following are the letters and their meanings in the control file. Control File Lines and Purpose LetterDefinedPurposeA&LPRng;Identifier for jobCRFC1179Class for banner pageHRFC1179Host nameIRFC1179Indent PrintingJRFC1179Job name for banner pageLRFC1179Print banner pageMRFC1179Mail When PrintedNRFC1179Name of source filePRFC1179User identificationQ&LPRng;Queue nameR&LPRng;Accounting infoSRFC1179Symbolic link dataTRFC1179Title for prURFC1179Unlink data fileWRFC1179Width of outputZ&LPRng;Filter options1RFC1179troff R font2RFC1179troff I font3RFC1179troff B font4RFC1179troff S fontcRFC1179Plot CIF filedRFC1179Print DVI filefRFC1179Print formatted filegRFC1179Plot filekRFC1179Reserved for use by Kerberized &LPRng; clients and servers.lRFC1179Print file leaving control charactersnRFC1179Print ditroff output fileoRFC1179Print Postscript output filepRFC1179Print file with 'pr' formattRFC1179Print troff output filevRFC1179Print raster filezRFC1179Reserved for future use with the Palladium print system.
The A (Identifier) line was introduced to record a unique system wide job identifier for &LPRng; submitted jobs. This is basically formed from the user name, job number, and host at the time of submission. For example: papowell@h4+955 is job number 995 submitted by papowell from host h4. The C (Class) line is set by the lpr -C class option, and the value can be used to control printing. For example, the lpc class zone command would restrict job printing to only jobs with class zone. The H (hostname), P (username), and J (jobname) fields are used to identify the host and user which sent the job, and to provide information to be displayed by lpq when reporting job status. The L (print banner page) field is one that has caused many problems for users. RFC1179 indicates that its presence causes the banner page to be printed, and its absence suppresses banner pages. The lpr -h option suppresses putting this line into the control file. Usually the L field is a duplicate of the P field. The M (mail information) field supplies a mail address for &LPRng; to send mail to when a job is completed. The N (file name) field is usually provided to identify the file name corresponding to the data file. This can be used to print names on page separators, etc. &LPRng; largely ignores this line. The I (indent) and W (width) fields are supposed to specify a page indent and width for printing. These fields are passed to filters if they are present. The Q (queue name) field is an &LPRng; extension, and contains the name of the print queue the job was originally sent to. The R (accounting info) field was added by &LPRng; to allow a specified account to be billed for job printing. The lpr -Rname option can be used to specify the accounting name. The S (symbolic link) and U (unlink after printing) lines were used by the original BSD S lines and force the U lines to refer only to job data files. This closes a nasty security loophole on non-&LPRng; print spoolers. The T (pr job title) is used with the lpr -p operation to supply a banner to the pr program. The Z (filter options) value is specified with lpr -Zoption and is passed to the data file filters during the printing operation. All of the lower case letters are reserved for format specifications for data files. In the control file, these are followed by the name of the data file to which they correspond. While in principle different data files in the control file can have different formats, this has not been implemented in any known spooling system. <application>lpq</application> Requests The RFC1179 protocol specifies that lpq print status requests can be sent to the lpd server. The lpq requests have the format: \003printer [id]* \n short \004printer [id]* \n long \009printer [id]* \n &LPRng; extension- verbose The lpd print server will then return queue status and close the data connection. RFC1179 does not state in any manner what the format of the queue status should be. Thus, implementors have been free to augment or change the status as they like. Even the BSD The id values are used to select the jobs to be displayed. &LPRng; displays any job whose ID, hostname, or user name information from the control file A, H, or P fields match any of the id values. Note that since there is no identification of the information requestor, then restriction of information is almost impossible. <application>lprm</application> Requests The RFC1179 protocol specifies that lprm job removal requests can be sent to the lpd server. The lpq requests have the format: \005printer user [id]* \n The lpd print server will search the specified print queue and remove any job whose ID, hostname, or user name information from the control file A, H, or P fields match any of the id values and for which the user has permission to perform a removal operation. Most RFC1179 compatible spoolers use the user information in the request as the name of the user which spooled the job. However, in a network environment this is extremely easy to fabricate, and is at best a weak type of authentication. LPC Requests &LPRng; has extended the RFC1179 protocol to allow queue and printer control commands to be sent to the \006printer user key [options] The following commands are supported. LPC Commands CommandOperationCommandOperation active [printer[@host]]check to see if server accepting connections abort (printer[@host] | all) terminate server process printing job disable (printer[@host] | all) disable queueing debug (printer[@host] | all) debugparms set debug level for printer enable (printer[@host] | all) enable queueing hold (printer[@host] | all) (name[@host] | job | all)* hold job holdall (printer[@host] | all) hold all jobs on kill (printer[@host] | all) stop and restart server lpd [printer[@host]] get lpq (printer[@host] | all) (name[@host] | job | all)* invoke lprm (printer[@host] | all) (name[@host]|host|job| all)* invoke move printer (user|jobid)* target move jobs to new queue noholdall (printer[@host] | all) hold all jobs off printcap (printer[@host] | all) report printcap values quit exit LPC redirect (printer[@host] | all) (printer@host | off )* redirect jobs release (printer[@host] | all) (name[@host] | job | all)* release job reread [printer[@host]] start (printer[@host] | all) start printing status (printer[@host] | all) status of printers stop (printer[@host] | all) stop printing topq (printer[@host] | all) (name[@host] | job | all)* reorder job defaultq default queue for local (printer | all) client printcap and configuration information server (printer | all) server printcap and configuration information
Many of these commands support extremely specialized operations for print queue management, However, the following are the most commonly used and are supported by the BSD start, stop, enable, disable Start and stop will start and stop printing for a specified queue. Enable and disable enable and disable sending and/or accepting jobs for the queue. abort, kill Abort will cause the process doing the actual job printing to be terminated. Kill does an abort, and then restarts the printing process. These commands are used to restart a queue printing after some disaster. topq Places selected jobs at the top of the print queue. status Shows a status display of the print spools on the server. The following commands are extensions to the basic set provided by the BSD lpq, lprm Invokes the lpq or lprm program from lpc. Useful when in the interactive mode. hold, holdall, release The hold command will cause the selected jobs to be held until released. The holdall jobs sets all jobs submitted to the queue to be held until released. The release command releases jobs for printing. If a job has had an error and is in the error state, the release command will cause it to be reprinted. move, redirect The move command will move selected jobs to the specified spool queue. The redirect command sends all jobs submitted to the queue to be sent to the specified queue. active, lpd, reread The active command will connect to the server for the printer. This is used to check to see if non-&LPRng; print servers are active. The lpd command will connect to the server and get the process id (PID) of the lpd server. The reread command causes a SIGHUP signal to be sent to the lpd process, causing it to reread the lpd.conf, printcap, and lpd.perms files. This is done when configuration information has been modified and the administrator wants to have the server use the new information. debug This is a desperation facility for developers that allows dynamic enabling of debug information generation. Not normally used in general operation. local, server These commands will print out the configuration information in the local lpd.conf file, as well as the printcap information for the specified printers; client prints what the &LPRng; clients (lpr, lpq, ...) would use while server prints what the &LPRng; server (lpd) would use if running on this host. This is an extremely useful diagnostic tool for administrators. Not normally used in general operation. Block Job Transfer Options used: send_block_format FLAG Transfer job as a block In normal job transfer operations, the sender and receiver have a handshake interaction in order to transfer a print job. Each file is sent individually. The send_block_format option forces a Block Job Transfer operation. This causes the sender to transfer a single file containing all the job printing information, including control file and data files. The transfer command line has the form: \007printer size\n The receiver will return any acknowledgement of a single 0 octet, and then the size bytes of the job will be transferred by the sender. At the end of the transfer a single 0 octet is added, and the receiver will indicate success by returning a single 0 octet. Any other value returned by the receiver indicates an error condition. The file transferred by the sender is simply the command lines that it would have normally sent for job transfer, followed by the control or data file values. Authenticated Transfer RFC1179 does not provide any authentication or encryption mechanism for the transfer of jobs or commands to the lpd print server. The Authenticated Transfer operation was added to allow an encrypted or authenticated transfer of print jobs or commands. Since there are various restrictions on the incorporation of authentication facilities into programs, &LPRng; supports authentication by providing a simple interface to encryption programs. The idea is that when authentication is required when sending a job, &LPRng; will generate a block transfer job as described for the Block Job Transfer operation, and then invoke a set of programs to encryt and transfer the file, and encrypt and transfer the returned status. Similarly, when sending a command, the command information will be placed in a file and the encrypted file will be transferred. This technique means that the programs and support to do encryption are external to &LPRng;, and can use any type of method that they choose to implement the secure and/or authenticated transfer.