PRINTCAP(5) BSD File Formats Manual PRINTCAP(5)NAMEprintcap — printer capability data base
SYNOPSISprintcapDESCRIPTION
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 dele‐
tion 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, 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 discus‐
sion on how to setup the database for a given printer.
CAPABILITIES
Refer to termcap(5) for a description of the file layout.
Name Type 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
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 like `fc' but set bits
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
mx num 1000 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)
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
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 like `xc' but set bits
If the local line printer driver supports indentation, the daemon must
understand how to invoke it.
The lp entry can specify either a device in the ``/dev'' directory or a
printer accessible via the network using the syntax:
:lp=port @host printcap:
where host is the network name of the printer and port is the TCP port
number to use for the network connection. This works both for printers
directly connected to the network (and which understand TCP/IP) as well
as for many terminal servers that support printers via their serial
and/or parallel ports.
FILTERS
The lpd(8) daemon creates a pipeline of filters to process files for var‐
ious 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 liter‐
ally) is specified to lpr. 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.
LOGGING
Error messages generated by the line printer programs themselves (that
is, the lp* programs) are logged by syslog(3) using the LPR facility.
Messages printed on stderr of one of the filters are sent to the corre‐
sponding lf file. The filters may, of course, use syslog themselves.
Error messages sent to the console have a carriage return and a line feed
appended to them, rather than just a line feed.
ADMINISTRATION
In a networked environment with many hosts, it is convenient to use the
same printcap file on all machines. This is accomplished by specifying
the complete set of entries for every printer on all machines, including
entries for both the rm and lp capabilities. This is possible because
the lpd daemon matches the rm printcap entry with the local host name and
only opens the line printer specified by lp if the names match. Other‐
wise the lp entry is ignored and the spooled file is sent on to the
remote machine for printing.
SEE ALSOtermcap(5), lpc(8), lpd(8), pac(8), lpr(1), lpq(1), lprm(1)
4.3 BSD Line Printer Spooler Manual.
HISTORY
The printcap file format appeared in 4.2BSD.
4.2 Berkeley Distribution May 10, 1995 4.2 Berkeley Distribution
