printcap

PRINTCAP(5)                    File Formats Manual                   PRINTCAP(5)

NAME
     printcap — printer capability data base

SYNOPSIS
     printcap

DESCRIPTION
     The Printcap function is a simplified version of the termcap(5) data base
     used to describe line printers.  The spooling system accesses the printcap
     file every time it is used, allowing dynamic addition and deletion of
     printers.  Each entry in the data base is used to describe one printer.
     This data base may not be substituted for, as is possible for termcap(5),
     because it may allow accounting to be bypassed.

     The default printer is normally lp, though the environment variable PRINTER
     may be used to override this.  Each spooling utility supports an option, -P
     printer, to allow explicit naming of a destination printer.

     Refer to the 4.3 BSD Line Printer Spooler Manual for a complete discussion
     on how to setup the database for a given printer.

CAPABILITIES
     Refer to termcap(5) for a description of the file layout.

     Name       Type      Default                Description
     af         str       NULL                   name of accounting file
     br         num       none                   if lp is a tty, set the baud
                                                 rate (ioctl(2) call)
     cf         str       NULL                   cifplot data filter
     ct         num       120                    TCP connection timeout in
                                                 seconds
     df         str       NULL                   tex data filter (DVI format)
     du         num       1                      UID to run daemon as
     ff         str       ‘\f’                   string to send for a form feed
     fo         bool      false                  print a form feed when device
                                                 is opened
     gf         str       NULL                   graph data filter (plot(3)
                                                 format
     hl         bool      false                  print the burst header page
                                                 last
     ic         bool      false                  driver supports (non standard)
                                                 ioctl to indent printout
     if         str       NULL                   name of text filter which does
                                                 accounting
     lf         str       /dev/console           error logging file name
     lo         str       lock                   name of lock file
     lp         str       /dev/lp                device name to open for output,
                                                 or port@machine to open a TCP
                                                 socket
     mc         num       0                      maximum number of copies which
                                                 can be requested on lpr(1),
                                                 zero = unlimited
     ms         str       NULL                   if lp is a tty, a comma-
                                                 separated, stty(1)-like list
                                                 describing the tty modes
     mx         num       0                      maximum file size (in BUFSIZ
                                                 blocks), zero = unlimited
     nd         str       NULL                   next directory for list of
                                                 queues (unimplemented)
     nf         str       NULL                   ditroff data filter (device
                                                 independent troff)
     of         str       NULL                   name of output filtering
                                                 program
     pc         num       200                    price per foot or page in
                                                 hundredths of cents
     pl         num       66                     page length (in lines)
     pw         num       132                    page width (in characters)
     px         num       0                      page width in pixels
                                                 (horizontal)
     py         num       0                      page length in pixels
                                                 (vertical)
     rc         bool      false                  when sending to a remote host,
                                                 resend copies (see below)
     rf         str       NULL                   filter for printing FORTRAN
                                                 style text files
     rg         str       NULL                   restricted group. Only members
                                                 of group allowed access
     rm         str       NULL                   machine name for remote printer
     rp         str       lp                     remote printer name argument
     rs         bool      false                  restrict remote users to those
                                                 with local accounts
     rw         bool      false                  open the printer device for
                                                 reading and writing
     sb         bool      false                  short banner (one line only)
     sc         bool      false                  suppress multiple copies
     sd         str       /var/spool/lpd         spool directory
     sf         bool      false                  suppress form feeds
     sh         bool      false                  suppress printing of burst page
                                                 header
     sr         str       NULL                   file name to hold statistics of
                                                 each datafile as it is received
     ss         str       NULL                   file name to hold statistics of
                                                 each datafile as it is sent
     st         str       status                 status file name
     tf         str       NULL                   troff data filter (cat
                                                 phototypesetter)
     tr         str       NULL                   trailer string to print when
                                                 queue empties
     vf         str       NULL                   raster image filter

     Each two-letter capability has a human-readable alternate name.

     Short form    Long form
     af            acct.file
     br            tty.rate
     cf            filt.cifplot
     ct            remote.timeout
     df            filt.dvi
     du            daemon.user
     ff            job.formfeed
     fo            job.topofform
     gf            filt.plot
     hl            banner.last
     if            filt.input
     lf            spool.log
     lo            spool.lock
     lp            tty.device
     mc            max.copies
     ms            tty.mode
     mx            max.blocks
     nf            filt.ditroff
     of            filt.output
     pc            acct.price
     pl            page.length
     pw            page.width
     px            page.pwidth
     py            page.plength
     rc            remote.resend_copies
     rf            filt.fortran
     rg            daemon.restrictgrp
     rm            remote.host
     rp            remote.queue
     rs            daemon.restricted
     rw            tty.rw
     sb            banner.short
     sc            job.no_copies
     sd            spool.dir
     sf            job.no_formfeed
     sh            banner.disable
     sr            stat.recv
     ss            stat.send
     st            spool.status
     tf            filt.troff
     tr            job.trailer
     vf            filt.raster

     If the local line printer driver supports indentation, the daemon must
     understand how to invoke it.

FILTERS
     The lpd(8) daemon creates a pipeline of filters to process files for
     various printer types.  The filters selected depend on the flags passed to
     lpr(1).  The pipeline set up is:

           p       pr | if regular text + pr(1)
           none    if      regular text
           c       cf      cifplot
           d       df      DVI (tex)
           g       gf      plot(3)
           n       nf      ditroff
           f       rf      Fortran
           t       tf      troff
           v       vf      raster image

     The if filter is invoked with arguments:

           if [-c] -wwidth -llength -iindent -n login -h host acct-file

     The -c flag is passed only if the -l flag (pass control characters
     literally) is specified to lpr(1).  The Width function and length specify
     the page width and length (from pw and pl respectively) in characters.  The
     -n and -h parameters specify the login name and host name of the owner of
     the job respectively.  The Acct-file function is passed from the af
     printcap entry.

     If no if is specified, of is used instead, with the distinction that of is
     opened only once, while if is opened for every individual job.  Thus, if is
     better suited to performing accounting.  The of is only given the width and
     length flags.

     All other filters are called as:

           filter -xwidth -ylength -n login -h host acct-file

     where width and length are represented in pixels, specified by the px and
     py entries respectively.

     All filters take stdin as the file, stdout as the printer, may log either
     to stderr or using syslog(3), and must not ignore SIGINT.

REMOTE PRINTING
     When printing to a remote printer using rm, it is possible to use either if
     or of.  If both are specified, of is ignored.  Both filters behave the same
     except that they are passed different arguments as above.  Specifically,
     the output filter is terminated and restarted for each file transmitted.
     This is necessary in order to pass the resulting size to the remote lpd(8).

     If the -p flag was passed to lpr(1), pr(1) is not executed locally, but is
     requested of the remote lpd(8).  Any input filtering via if will therefore
     happen before pr(1) is executed rather than afterwards.

     There are some models of network printers which accept jobs from lpd(8),
     but they ignore the control file for a job and simply print each data file
     as it arrives at the printer.  One side-effect of this behavior is that the
     printer will ignore any request for multiple copies as given with the -#
     flag on the lpr(1) command.  The rc entry will cause lpd(8) to resend each
     data file for each copy that the user originally requested.  Note that the
     rc entry should only be specified on hosts which send jobs directly to the
     printer.

     If lp is specified as port@machine (and rm is not in use), print data will
     be sent directly to the given port on the given machine.

TRANSFER STATISTICS
     When a print job is transferred to a remote machine (which might be another
     unix box, or may be a network printer), it may be useful to keep statistics
     on each transfer.  The sr and ss options indicate filenames that lpd should
     use to store such statistics.  A statistics line is written for each
     datafile of a job as the file is successfully transferred.  The format of
     the line is the same for both the sending and receiving side of a transfer.

     Statistics on datafiles being received would be used on a print server, if
     you are interested in network performance between a variety of machines
     which are sending jobs to that print server.  The print server could
     collect statistics on the speed of each print job as it arrived on the
     server.

     Statistics on datafiles being sent might be used as a minimal accounting
     record, when you want to know who sent which jobs to a remote printer, when
     they were sent, and how large (in bytes) the files were.  This will not
     give include any idea of how many pages were printed, because there is no
     standard way to get that information back from a remote (network) printer
     in this case.

LOGGING
     Error messages generated by the line printer programs themselves (that is,
     the lpd(8) and related programs) are logged by syslog(3) using the LPR
     facility.  Messages printed on stderr of one of the filters are sent to the
     corresponding lf file.  The filters may, of course, use syslogd(8)
     themselves.

     Error messages sent to the console have a carriage return and a line feed
     appended to them, rather than just a line feed.

SEE ALSO
     lpq(1), lpr(1), lprm(1), hosts.lpd(5), termcap(5), chkprintcap(8), lpc(8),
     lpd(8), pac(8)

     4.3 BSD Line Printer Spooler Manual.

HISTORY
     The printcap file format appeared in 4.2BSD.

                                October 11, 2000