PRINTCAP(5)

NAME
printcap - printer capability database

SYNOPSIS
printcap

DESCRIPTION
The printcap file is a simplified version of the termcap(5) database 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 database is used to describe one printer. This database 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, -Pprinter, to allow explicit naming of a destination printer.

Refer to the for a complete discussion on how to set up 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 baud rate
(ioctl(2) call)
cf | str | NULL | cifplot data filter
df | str | NULL | tex data filter
(DVI format)
fc | num | 0 | if lp is a tty, clear flag bits
(<sgtty.h>)
ff | str | ‘\f’ | string to send for a form feed
fo | bool | false | print a form feed when device is opened
fs | num | 0 | if lp is a tty, set flag bits
(<sgtty.h>)
gf | str | NULL | graph data filter
(plot(3) format)
hl | bool | false | print the burst header page last
ic | bool | false | 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 | local printer device, or port@host for remote
ms | str | NULL | list of terminal modes to set or clear
mx | num | 1000 | max file size (in
BUFSIZ blocks); 0=unlimited
nd | str | NULL | next directory for queues list (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)
rf | str | NULL | filter for printing
FORTRAN style text files
rg | str | NULL | restricted group-only group members can access
rm | str | NULL | machine name for remote printer
rp | str | ``lp'' | remote printer name argument
rs | bool | false | remote users must have a local account
rw | bool | false | open 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
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
xc | num | 0 | if lp is a tty, clear local mode bits
(tty(4))
xs | num | 0 | if lp is a tty, set local mode bits
(tty(4))

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

FILTERS
If a printer is specified via lp (either local or remote), the lpd(8) daemon creates a pipeline of “filters” to process files for various printer types. The pipeline is not set up for remote printers specified via rm unless the local host is the same as the remote printer host given. 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). width 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.

LOGGING
Error messages generated by the line printer programs themselves 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 syslog(3) 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), termcap(5), lpc(8), lpd(8), pac(8) 4.3 BSD Line Printer Spooler Manual.

HISTORY
The printcap file format appeared in 4.2BSD.