Section 24.3. Printing (Topic 1.107)

24.3. Printing (Topic 1.107)

24.3.1. Objective 2: Manage Printers and Print Queues

• Printers are assigned to queues, which are managed by lpd, the print daemon. lpd listens for inbound print requests, forking a copy of itself for each active print queue.

• lpr submits jobs to print queues.

• lpq queries and displays queue status.

• lprm allows jobs to be removed from print queues.

• lpc allows root to administer queues; it has both interactive and command-line forms.

• Filters translate data formats into a printer definition language.

• Spool directories hold spooled job data.

24.3.2. Objective 3: Print Files

• Files are printed with the lpr command:

   # lpr /etc/lilo.conf # man -t 5 myfile.txt | lpr -Pqueue2 

  
  

24.3.3. Objective 4: Install and Configure Local and Remote Printers

24.3.3.1. /etc/printcap

• New printer definitions are added to /etc/printcap:

   lp|ljet:\         :sd=/var/spool/lpd/lp:\         :mx#0:\         :sh:\         :lp=/dev/lp0:\         :if=/var/spool/lpd/lp/filter:         :lf=/var/spool/lpd/lp/log: 

  
  

  The lines in this example are defined as follows:

  
  

  lp|ljet:\

  This parameter defines two alternate names for the printer, lp or ljet.

  
  

  sd=spool_directory

  This parameter specifies the spool directory, under /var/spool/lpd.

  
  

  mx=max_size

  The maximum size of a print job in blocks. Setting this to #0 indicates no limit.

  
  

  sh

  Suppress header pages. Placing this attribute in printcap sets it, eliminating the headers.

  
  

  lp=printer_device

  The local printer device, such as a parallel port.

  
  

  if=input_filter

  The input filter to be used. See "Filters" in Chapter 15 for additional information.

  
  

  lf=log_file

  The file where error messages are logged.

24.3.3.2. Filters

• APSfilter is implemented as executable scripts. Installation configures /etc/printcap automatically. Multiple queues may be defined to give the user access to specific printer capabilities.

• Magicfilter is a binary program; installation does not automatically create print queues.

24.3.3.3. Remote queues and Samba printers

• Printing on a remote system or network printer is done through a local queue. /etc/printcap for the local queue looks something like this:

   rlp:\         :sd=/var/spool/lpd/rlp:\         :rm=lphost:\         :rp=rlp:\         :mx#0:\         :sh:\         :if=/usr/local/bin/magicfilter    : 

  
  

• Printing to Windows printers is similar and uses the smbprint filter:

   winpr:\         :sd=/var/spool/lpd/winpr:\         :mx#0:\         :sh:\         :if=/usr/bin/smbprint: