NAME
printcap —
printer capability data base
SYNOPSIS
printcap |
DESCRIPTION
The printcap data base is 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.
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 set up the database for a given printer.
CAPABILITIES
Refer to capfile(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 |
| 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 to local printer, or port@host for remote printer/printer on print server |
| ms | str | NULL |
list of terminal modes to set or clear |
| 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 |
| pf | str | NULL |
filter for printing PostScript files |
| 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 or port@host for a remote printer on a port other than the standard port. (also suppress the burst page, see NOTES) |
| 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/output/lpd | spool directory |
| sf | bool | false | suppress form feeds |
| sh | bool | false | suppress printing of burst page header (local only, see NOTES) |
| 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.
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 o pf PostScript f rf Fortran t tf troff v vf raster image
The if filter is invoked with arguments:
if
[-c]
-wwidth
-llength
-iindent
-n login
[-j jobname]
-h host acct-fileThe -c flag is passed only if the
-l flag (pass control characters literally) is
specified to lpr(1). The 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 -j parameter is optional and
specifies the name of the print job if available. The
acct-file option 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
[-j jobname]
-h host acct-filewhere 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.
Filters can communicate errors to lpd by their exit code and by modifying the mode of the spool lock file as follows:
- Exit code
- Description
- 0
- Success.
- 1
- An attempt is made to reprint the job and mail is sent if it fails.
- 2
- lpd(8) silently discards the job.
- n
- lpd(8) discards the job and mail is sent.
- lock code
- Description
- u+x
- Stop printing and leave queue disabled (S_IXUSR).
- o+x
- Rebuild the queue (S_IXOTH).
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
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), capfile(5), lpc(8), lpd(8), pac(8)
4.3 BSD Line Printer Spooler Manual.
NOTES
The sh flag is a function of the spooler with the locally attached printer, and so has no effect when used with rm. NetBSD never adds a burst page when used as a remote spooler. To suppress the burst page for other systems or dedicated devices, refer to the documentation for those systems or devices.
HISTORY
The printcap file format appeared in
4.2BSD.