NAME
printcap - printer capability data base
SYNOPSIS
printcap database
DESCRIPTION
The format of the LPRng printcap database was based on the termcap(5)
data base file format. Entries in the printcap Each entry in the data
base is used to define various options and values to control the
printing and spooling of print jobs.
LPD.CONF, SYSTEM AND USER PRINTCAP FILES
Default configuration values are read from the LPRng configuration file
//etc/lprng/lpd.conf, consult the lpd.conf(5) man page for details
about them. The system printcap file //etc/printcap contains
information common to all users and the LPRng printing system.
Finally, the user printcap files is in ${HOME}/.printcap and contain
user configurable information for printer information. The values in
the user printcap file override values in the printcap file which
override the default values in the //etc/lprng/lpd.conf file.
The user printcap file is used by client programs such as lpr , lprm ,
lpq , and lpq to allow the user to define either a special set of
printers, provide additional configuration information, or to modify
default settings in the //etc/printcap, or //etc/lprng/lpd.conf file.
CAPABILITIES
The printcap database files format is based on the termcap (5) database
format, modified as follows. Leading whitespace on each line is
discarded, and blank lines or lines which then start with a comment
character (#) are discarded. A line which does not start with a colon
(:) or bar (|) starts a printer entry definition. Lines ending with a
backslash (\) are assumed to continue to the next line; this is for
compatibility with other historical printcap file formats. Trailing
blanks and tabs (whitespace) for an option value are deleted unless the
last one is escaped with a backslash (‘‘\’’). If a colon character
value is required then the \: escape sequence can be used, e.g.:
dest=ftp\://address/file.
A printer definition starts with a primary printer name, followed by
zero or more alternative printer names, followed by a set of keyword
entries and values. For example:
#comment
# primary printer name
lp
#alternate names
|lp2|lp3
|Example of a printer
:sd=/usr/spool/LPD/lp
:rw:lp=/dev/lp:mx#100
include /etc/printcap/mainprintcap
The special printcap definition include will read the named file, which
must have an absolute pathname, as the next set of printcap entries.
Keywords can be 1 to an indefinite number of characters long, and are
case sensitive. Values for keywords can be strings (:st=string:),
signed integer values using the C language notation,
(:nu#12:max#-2:mask#0x1EF:), or flags (:flag: to set to 1, :flag@: to
clear to 0). Integer values must be representable as 32 bit 2’s
complement numbers; care should be taken with extremely large numbers.
If the primary name of a printcap entry starts with a punctuation
character, then the entry may be referenced using the tc capability,
but is ignored otherwise. This allows common printcap information to
be placed in a single entry.
The special printcap entry oh (i.e. - only this host) may be used to
select a printcap entry for use by one or more hosts. The oh entry can
be a list of one or more host names or glob type of patterns. These
patterns are first applied to the host’s fully qualified domain name,
and then used to to a lookup of an IP address. If either the glob
match or the host has a matching IP address then the printcap entry is
selected for use. In addition, the server flag indicates that only the
LPD server is to use this printcap entry. This allows client and
server printcap information be to be segregated in a simple manner.
The following is a list of the keywords currently used by the LPRng
software. Many of these keywords are used only by the LPD server,
others are used by the client programs LPR, LPC, LPRM, PAC, as well as
the server. In the Use column in the table below, an A stands for all
programs, D stands for lpd, and R stands for the client programs such
as LPR.
Some of these entries can only appear or have an effect if they are in
the lpd.conf initialization file. See lpd.conf(5) for further details.
ENTRIES BY ALPHABETICAL ORDER
FL Use Type Default Description
Xf D str NULL output filter for format X (used by lpd).
’filter’ sets default filter
ab D bool false always print banner, ignore lpr -h option
achk D bool false
If TRUE LPD and the :as specifies a remote host or
filter or the :af specifies a remote host or filter
then after writing the accounting information to the
destination a reply will be read. The value of the
reply determines how the job is to be handled.
ae D str accounting format for end of job or a program to run
to record accounting information (see also af, la, ar
and Accounting).
af D str NULL
accounting file, filter, or remote accounting server
(see also la, ar, as, ae, achk). If format is |/path then
the program will be started and accounting information
will be written to the program STDIN. If the format
host%port, a tcp/ip connection will be made to port
on host and the accounting information written to the
remote host. In both of these cases the write operation
must succeed or an error will result. If the format
is neither of these cases then the value will be treated
as a file and accounting information appended to the file
if it exists. The accounting file will not be created,
it must exist for LPD to append data to it.
The :as and :ae fields have the accounting information.
ah D bool false auto-hold - job held until explicitly released
all A str NULL a list of all printers; (see ALL PRINTERS)
allow_duplicate_flags A bool false
allow duplicate command line flags; last overwrites earlier
allow_getenv A bool (compile time)
allows LPRng software to use the LPD_CONF environment variable
to specify the location of a configuration file. This is
for testing only.
allow_user_logging A bool false
if mail is requested using lpr -mhost%port,prot operations,
and the allow_user_logging flag is true, then job logging
information will be sent to host%port,prot.
allow_user_setting A str NULL
allow these users to impersonate other users with the
lpr -U user@host, lpc -U user@host, etc., options
append_z A str
append these options to the -Z options for the job
ar D bool true write remote transfer accounting (if af, and as/ae set)
architecture A str (compile time)
architecture the software was compiled for. (Obsolete.)
as D str accounting format for start of job or a program to run
to record accounting information (see also af, la, ar
and Accounting).
auth R str NULL
client to server authentication type
be D str banner printing program for end (overrides bp, hl)
bk R bool false Berkeley-compatible: be strictly RFC-compliant
or more exactly, BSD LPR compatible when sending jobs.
bk_filter_options D str (see source code)
when bk flag set, options for non OF print filters
bk_of_filter_options D str (see source code)
when bk flag set, options for OF print filters
bkf R bool false
use bk_filter_options and bk_of_filter_options when
invoking print filter.
bl D str banner line - sent to banner printer program
default: $-’C:$-’n Job: $-’J Date: $-’t
expands to: Class:User Job: job Date: date
This is to force compatibility with vintage print filters
that require a non-standard banner string. Usually used with
:sb: option.
bp D str banner printing program (see hl)
(default: configuration variable default_banner_printer)
bq_format D str l format of output from bounce queue filters
br D num none if lp is a tty, set the baud rate (see ty)
break_classname_priority_link A flag false
Do not set priority to first letter of class name
bs D str banner printing program for start (overrides bp, hl)
cf D str NULL cifplot data filter
check_for_nonprintable R bool false
lpr checks f and p formats for printable files
check_for_protocol_violations R bool false
check for RFC1179 protocol violations
chooser D str load balance queue destination chooser program
chooser_interval D num 10
load balance queue does checks for a
destination queue available at this interval
chooser_routine D bool false
use the user provided chooser routine for this queue
class_in_status A bool true
show class name in lpq status rather than priority
cm A str NULL comment identifying printer (LPQ)
config_file A str //etc/lprng/lpd.conf
location of LPRng configuration information. Compile
time option only - see allow_getenv.
connect_grace A num 0
time between jobs to allow printer recovery
connect_interval A num 10
time between open or connection attempts
connect_timeout A num 10
timeout value for connection or open
control_file_line_order D str NULL
Put the control file lines in a specific order
control_filter D str NULL
Filter for control file. Used when sending job to remote
spool queue.
create_files D bool false
create log, debug, etc., files automatically
db A str NULL LPD debug options when serving this queue.
See lf (log file) entry as well.
default_format R str f
default format for printing jobs
default_permission D str A
default permission for operation
default_printer A str lp
default printer for printing jobs
default_priority R str A
default priority for printing jobs
default_remote_host A str localhost
default remote host for printing operations
default_tmp_dir A str /tmp
default temporary directory
destinations D str NULL
names of printers that lpq/lprm should talk to
find a job that has been processed by a router
script (see README.routing)
df D str NULL tex data filter (DVI format)
done_jobs D num 1
retain status for last N jobs
done_jobs_max_age num 0
remove status older than N seconds (0 - no removal)
exit_linger_timeout A num 10
socket SO_LINGER timeout value
fd D bool false if true, no forwarded jobs accepted
ff D str ‘‘\f’’ string to send for a form feed (see INITIALIZATION)
filter D str NULL
default filter to use for printing file
filter_ld_path D str (see source)
the LD_LIBARY_PATH environment variable value for filters
filter_options D str (see source code)
when bk flag clear, options for non OF print filters
filter_path D str (default ’/bin:/usr/bin’)
the PATH environment variable value for filters
filter_poll_interval D num 30
interval to poll OF filter
filter_stderr_to_status_file D bool false
set the filter STDERR to the status file and do
no report errors in the queue status file.
fo D bool false print a form feed when device is opened
force_fqdn_hostname A bool FALSE
Force a fully qualified host name in control file
force_ipadddr_hostname A bool FALSE
Force the IP address of the host to be used for the
hostname in control file
force_localhost A bool TRUE
Forces the clients programs (lpr, lpc, etc.)
to send all print jobs and requests to the server running
on the localhost entry for action. This flag effectively
forces BSD LPR behavior.
force_lpq_status D str NULL
Specifies a list of LPQ formats and hosts which get status
returned in this format. For example
force_lpq_status=s=pc*;l=mac* will cause hosts whose
FQDN matches pc* to get short status and those which
match mac* to get long format.
force_queuename A str NULL
When :qq: flag or use_queuename configuration is enabled,
specifies the queuename to be used for control file Q
information.
ff_separator D bool false
need form feeds to separate job files
fq D bool false print a form feed when device is closed
full_time D bool detailed time format specification in log messages
fx A str NULL valid output filter formats
i.e. ‘‘flp’’ would allow f, l, and p
default is to allow all formats
gf D str NULL graph data filter (plot (3X) format)
generate_banner D bool false
generate a banner when forwarding job
group D str daemon LPD server group id for execution
hl D bool false print banner after job instead of before
if D str NULL filter command, run on a per-file basis
ignore_requested_user_priority D bool false
Ignore the requested user priority when ordering jobs.
Prevents students... um... users from queue jumping.
ipv6 A bool false Use IPV6
keepalive A bool true
set socket SO_KEEPALIVE option
kerberos_keytab D str /etc/lpd.keytab
Kerberos lpd server keytab file
kerberos_life D str NULL
Kerberos lpd server key lifetime
kerberos_renew D str NULL
Kerberos lpd server key renewal time
kerberos_server_principle D str NULL
Kerberos remote lpd server principle
kerberos_service D str lpr
Kerberos service used in principle requests
la D bool true write local printer accounting (if af is set)
ld D str NULL leader string printed on printer open (see INITIALIZATION)
lf D str ‘‘log’’ error and debugging log file (LPD)
lk D bool false lock the lp device to force arbitration
lockfile D str /var/spool/lpd/lpd
lpd lock file (used only in lpd.conf).
The lpd_port port value is appended
to the lockfile value to provide a unique lockfile
even when different versions of LPRng are running
on the same system.
logger_destination D str NULL
destination for logging information. Format is
host%port
logger_max_size D num 1024
logger file maximum size in K
logger_path D str NULL
logger file pathname
logger_timeout D num 0
logger connection timeout. 0 is no timeout.
longnumber D bool false
use 6 digit job numbers
lp D str NULL device name or pipe to send output to
lpd_bounce A bool FALSE
Forces lpd to filter jobs and then forward them
as a single file
(See Bounce Queues)
lpd_force_poll A bool FALSE
Forces lpd to periodically poll lpd queues.
lpd_poll_time A num 600
Check queues for work at this interval; start queues
in groups of ’lpd_poll_servers_started’ at intervals
of ’lpd_poll_start_interval’ seconds
lpd_poll_start_interval A num 10
Start ’lpd_poll_servers_started’ queue servers at this
interval.
lpd_poll_servers_started A num 10
Start ’lpd_poll_servers_started’ queues at once
lpd_port D str printer
format is [ipaddr%]port. If the ipaddr is present
then the lpd listening socket is bound to the specified
ip address and port only, otherwise it is bound to all
interfaces. If the port value is not a number then the
then the getservbyname() system call is used to get the
port number.
lpd_printcap_path D str (see source)
printcap path for lpd, used instead of printcap path
(configuration value only)
lpr_bounce R bool true
Forces lpr to filter jobs and then send them.
(See Bounce Queues)
lpr_bsd R bool false
when set, LPR -m will not take argument, but will use
$USER value for return mail address.
mail_from D str NULL
specifies the user part of email From: address
mail_operator_on_error D str NULL
send mail to this user when LPD encounters printing error.
max_connect_interval A num 60
maximum time between connection attempts
max_log_file_size D num 0
maximum log file size in K bytes (0 is unlimited)
spool queue log file truncated to min_log_file_size
when value is nonzero and limited exceeded.
max_servers_active D num 0
maximum servers that LPD will allow to be active at one
time. 0 selects the system default, which is usually
pretty small, perhaps 10. (configuration value only).
max_status_line D num 79 maximum number of characters on an LPQ status line
max_status_size D num 10 maximum size (Kbytes) of status file
mc R num 1 maximum copies allowed
min_log_file_size D num 0 minimum size (Kbytes) of log file
min_status_size D num 2 minimum size (Kbytes) of status file
minfree D str 0
minimum space (in K) for spool directory
ml R num 32 minimum printable characters for printable check
ms_time_resolution D bool false
log time in milliseconds
mx R num 0 maximum job size in K, 0 = unlimited
nb D num 0 if non-zero, do a nonblocking open on lp device
nf D str NULL DITROFF data filter
network_connect_grace A num 0
time between attempts to send jobs to spooler
Useful when dealing with network printer using LPD
interface to allow a bit of time between jobs.
nline_after_file D bool false
put the N (filename) after the data file information
in the control file. Use to handle systems that want
it that way.
of D str NULL output filter, run once for all output
(used for banner printing, form feeds between files)
of_filter_options D str (see source code)
when bk flag clear, options for OF print filters
oh A str NULL Specific printcap entry for host;
(printcap entry ignored unless IP address of host and
entry value match. Entry is used first to do glob
style match against the host’s fully qualified domain name,
and then interpreted as a general IP address)
order_routine D bool false
use a user provided routine to generate queue order
information.
originate_port A str 512 1023
when originating a connection, use ports in this range.
pass_env A str PGPPASS,PGPPATH
if not the LPD server, sanitize and put these variables
in a filter environment variable list.
perms_path A str //etc/lprng/lpd.perms
location of perms file (used in lpd.conf)
pl D num 66 page length (in lines)
pr D str ‘‘/bin/pr’’ pr program for p format
prefix_o_to_z D bool false
prefix the control file O line to the control file
Z line.
prefix_z D str NULL
prefix the specified options to the control file
Z line.
prefix_z_to_o D bool false
prefix the control file Z line to the control file
O line.
printcap_path A str //etc/printcap
location of printcap file (only in lpd.conf)
ps A str ’’status’’ printer status file name
pw D num 132 page width (in characters)
px D num 0 page width in pixels (horizontal)
py D num 0 page length in pixels (vertical)
qq A bool false LPR - puts in the queue name (Q entry)
in the job control file when spooled or transferred.
LPD - when receiving or transferring a job,
if the queue name (Q entry) in the job control
file is not present, puts in the queue name.
queue_control_file D str control.%P
name of the queue control file
queue_lock_file D str %P
name of the queue lock file
queue_status_file D str status.%P
name of the queue status file
queue_unspooler_file D str unspooler.%P
name of the queue unspooler status file
remote_support A str NULL
if non-null, specifies allowed operations to remote queue.
R=lpr, M=lprm, Q=lpq, V = lpq -v, C=lpc. For example,
remote_support=RM would only allow LPR and LPRM operations.
remove_z D str null
remove these options from the control file Z line
report_server_as A str NULL
use the str value as the name of the server when reporting
LPQ or LPC status.
require_explicit_q Require a queue to be specified, do not use default
queue from printcap.
retry_econnrefused A bool true
if set, retry a connection to a remote system when an
ECONNREFUSED error is returned.
retry_nolink D bool true
if LPD is sending a job or opening a device for
printing and the value is true, then the connection or
device open is repeated indefinitely.
return_short_status D str NULL
Some legacy (non-LPRng) LPQ programs expect ’short’ status
to be returned. This option allows you to specify which hosts
will get it. The value is a list of hosts and/or IP addresses
and masks to which the LPD server will provide short status.
For example: return_short_status=192.8.0.0/16 will make LPD
return short status to all requests from hosts in subnet
192.8.0.0. (See short_status_length)
reuse_addr A bool false
if set, use SO_REUSEADDR on outgoing connection ports.
This reduces the problems with exhausting port numbers.
(usually only in lpd.conf)
reverse_lpq_status D str NULL
When a lpq status request arrives from one of the specified
hosts or IP addresses, then the LPQ status format is inverted.
For example, if reverse_lpq_status=host*,127.0.0.0/8,
then when a LONG status request arrives from host1 or from
IP address 127.0.0.1, the SHORT status will be returned.
reverse_priority_order D bool false
Make highest priority A, lowest Z
rf D str NULL filter for printing FORTRAN style text files
rg A str NULL (restrict to group members)
Restrict use of queue to users which are members of
specified groups.
rm A str NULL remote-queue machine (hostname) (with rp)
router D str NULL script that dynamically re-routes a job
(see README.routing)
rp A str NULL remote-queue printer name (with rm)
rw D bool false open the printer for reading and writing
safe_chars D str NULL
additional safe characters for control file contents
save_on_error D bool false
Save job when an error occurs to allow post-mortem
diagnostics or reprinting. This should only be set on
print queues. It is also a diagnostic aid.
save_when_done D bool false
Save job when done (printed, transferred) to allow
retry at a later time. This should only be set on
print queues. It is also a diagnostic aid.
sb D bool false short banner (one line only)
sd A str NULL spool directory (only ONE printer per directory!)
send_block_format A bool false
Use the LPRng extended ’block job’ job transmission
method to send a job to a remote site.
send_data_first A bool false send data files then control files
when sending a job to a remote host.
send_failure_action D str "remove"
Action on print or transmission failure after send_try
attempts; use the following codes:
’success’ (JSUCC) - treat as successful
’abort’ (JABORT) - abort printer
’retry’ (JRETRY) - retry job
’remove’ (JREMOVE)- remove job
’hold’ (JHOLD) - hold job
If the value is "|/filter", the filter will be run and
the number of attempts can be read from standard input.
The filter should exit with one of the error codes listed
above to cause the appropriate action.
send_job_rw_timeout A num 6000
timeout on read/write operations when sending job to
printer or remote host (0 value is no timeout)
send_query_rw_timeout A num 6000
timeout on read/write operations when performing a status
operation (0 value is no timeout)
send_try A num 3
number of times to try sending
or printing a job. 0 is infinite.
sendmail D str /usr/sbin/sendmail -oi -t
sendmail command to send mail to user. Flags must be set
so that address and other information is taken from
standard input.
server A bool false printcap entry for server only
server_auth_command A str NULL
authentication command for server program
server_tmp_dir D str /tmp
temporary directory for server to create files when there
is no spool directory.
server_user D str daemon server user name used in authentication operations
sf D bool true suppress form feed separators between job files
sh D bool false suppress headers and/or banner page
shell D str /bin/sh
SHELL environment variable value for filters
short_status_length D num 1
If the return_short_status value is used and has a match against
a requesting address, this amount of status is set by the
short_status_length option. For most legacy systems a 1 is
suitable (1 line of status).
socket_linger A num 10
if nonzero, forces a SO_LINGER operation to be done
on all TCP/IP connections. This usually corrects a problem
with missing last data transmissions to remote hosts.
spool_dir_perms D num 042700 permissions for spool directory
spool_file_perms D num 0600 permissions for spool file
ss D str NULL name of queue that server serves (with sv)
ssl_XXX D str NULL
SSL authentication and encryption options.
See lprng_certs(1) for details.
ssl_ca_file str A //etc/lprng/ssl.ca/ca.crt
SSL signing certificate file
ssl_ca_path str A NULL
SSL signing certificate directory. Default is
directory containing ssl_ca_file.
ssl_server_cert str A //etc/lprng/ssl.server/server.crt
SSL server certificate
ssl_server_password str A
SSL server certificate password
stalled_time D num 120
Time after which to report an active job as stalled
stop_on_abort D bool true
Stop processing queue when print filter aborts.
stty D str NULL stty settings for serial connected printer
suspend_of_filter D bool true
suspend OF filter and restart. If false, close filter
and start new one for each activity.
sv D str NULL names of servers for queue (with ss)
syslog_device D str /dev/console
name of syslog device to use if no syslog facility
tc A str NULL reference to a printcap entry to include as part of
the current entry.
tf D str NULL troff data filter (C/A/T phototypesetter)
tr D str NULL trailer string to print when queue empties
translate_format D str NULL
translate job format (similar to tr(1) utility)
on outgoing jobs.
Example: translate_format=pfml
p format changed to f, m format to l
translate_incoming_format D str NULL
translate job format (similar to tr(1) utility)
on incoming jobs. See translate_format.
use_date A bool true add date line (’D’) to control file
use_identifier R bool true
add job identifier lines (’A’) in the control file
use_info_cache D bool true cache printcap information
use_shorthost R bool false
use only the hostname for job control
and data file names. Host information in job file
will still be fully qualified domain name.
user D str daemon LPD effective user (EUID) for SUID operations
wait_for_eof D bool true
wait for EOF on input when readable IO device,
do not close immediately at job end.
vf D str NULL (Versatek) raster image filter
ENTRIES BY FUNCTION
See the alphabetical listing for detailed information.
Filters and Page Formats
Xf D str NULL output filter for format X (used by lpd)
’filter’ sets default filter
cf D str NULL cifplot data filter
control_filter D str NULL
Filter for control file. Used when sending job to remote
spool queue.
df D str NULL tex data filter (DVI format)
direct_read D bool false
if true, filters are given direct access to file.
This means no progress indication possible.
fx A str NULL valid output filter formats
i.e. ‘‘flp’’ would allow f, l, and p
default is to allow all formats
gf D str NULL graph data filter (plot (3X) format)
if D str NULL filter command, run on a per-file basis
lpd_bounce R bool false
Forces lpd to filter jobs and then forward them.
(See Bounce Queues)
lpr_bounce R bool false
Forces lpr to filter jobs and then send them.
(See Bounce Queues)
nf D str NULL DITROFF data filter
of D str NULL output filter, run once for all output
pl D num 66 page length (in lines)
pr D str ‘‘/bin/pr’’ pr program for p format
pw D num 132 page width (in characters)
px D num 0 page width in pixels (horizontal)
py D num 0 page length in pixels (vertical)
rf D str NULL filter for printing FORTRAN style text files
translate_format D str NULL
translate job format (similar to tr(1) utility)
only valid when transferring to remote spool queue.
Example: translate_format=pfml
p format changed to f, m format to l
tf D str NULL troff data filter (C/A/T phototypesetter)
vf D str NULL (Versatek) raster image filter
Banners
ab D bool false always print banner, ignore lpr -h option
be D str banner printing program for end (overrides bp, hl)
bp D str banner printing program (use hl to print banner at end)
bs D str banner printing program for start (overrides bp, hl)
hl D bool false print banner after job instead of before
sb D bool false short banner (one line only)
sh D bool false suppress headers and/or banner page, overrides ab
Accounting
ae D str accounting format for end of job or a program to run
to record accounting information (see also af, la, ar
and Accounting).
af D str NULL name of accounting file (see also la, ar)
ar D bool true write remote transfer accounting (if af, and as/ae set)
as D str accounting format for start of job or a program to run
to record accounting information (see also af, la, ar
and Accounting).
la D bool true write local printer accounting (if af is set)
Queue control
ah D bool false auto-hold - job held until explicitly released
bk R bool false backwards-compatible: be strictly RFC-compliant
bkf R bool false backwards-compatible filter: use Berkeley filter options
bqfilter D bool false if a bounce queue (sends jobs to remote site)
then when bqfilter true and a format filter is specified,
sends data files through format filter before transfer.
See also ’qq’.
cd D str NULL control information directory for LPD server
cm A str NULL comment identifying printer (LPQ)
fd D bool false if true, no forwarded jobs accepted
lf D str ‘‘log’’ error and debugging log file (LPD)
longnumber D bool false
use 6 digit job numbers
mc R num 1 maximum copies allowed
ml R num 32 minimum printable characters for printable check
minfree D str 0 minimum space (Kb) to be left in spool filesystem
You can also use nnnM for nnn megabytes.
mx R num 0 maximum job size (1Kb blocks, 0 = unlimited)
ps A str ’’status’’ printer status file name
nw A bool false spool dir is on an NFS file system
(take precautions when reading/writing files)
qq A bool false place queue information in control file. See
alphabetical for details.
rm A str NULL remote-queue machine (hostname) (with rp)
rp A str NULL remote-queue printer name (with rm)
sd A str NULL spool directory (only ONE printer per directory!)
ss D str NULL name of queue that server serves (with sv)
sv D str NULL names of servers for queue (with ss)
sc R bool false suppress multiple copies
use_auth A str NULL authentication to use
use_date A bool true add date line (’D’) to control file
use_identifier R bool true
add job identifier lines (’A’) in the control file
use_shorthost R bool false use only the hostname for job control
and data file names. Host information in job file
will still be fully qualified domain name.
Connection and Interface to Printer
db A num 0 debug level when using this printer
connect_interval A num 10
time between open or connection attempts
connect_timeout A num 10
timeout value for connection or open
(0 is infinite number)
ff D str ‘‘\f’’ string to send for a form feed (see INITIALIZATION)
fo D bool false print a form feed when device is opened
fq D bool false print a form feed when device is closed
ld D str NULL leader string printed on printer open (see INITIALIZATION)
lp D str NULL device name or pipe to send output to
lk D bool false lock the lp device to force arbitration
max_connect_interval A num 60
maximum time between connection attempts
nb D num 0 if non-zero, do a nonblocking open on lp device
retry_econnrefused A bool true
if set, retry a connection to a remote system when an
ECONNREFUSED error is returned.
retry_nolink D bool true
if LPD is sending a job or opening a device for
printing and the value is true, then the connection or
device open is repeated indefinitely.
rs D num 300 number of seconds between spool queue status scans
rt D num 3 number of times to try printing (0=infinite).
rw D bool false open the printer for reading and writing
save_on_error D bool false
See above.
save_when_done D bool false
See above.
send_failure_action D str remove
See above.
send_try alias for rt
sf D bool true suppress form feed separators between job files
socket_linger A num 10
if nonzero, forces a SO_LINGER operation to be done
on all TCP/IP connections. This usually corrects a problem
with missing last data transmissions to remote hosts.
tr D str NULL trailer string to print when queue empties
Serial Line Setup
br D num none if lp is a tty, set the baud rate (see ty)
stty D str NULL stty commands to set output line characteristics
alias is sy, ms
xs D num 0 like ‘xc’ but set bits (see STTY)
Miscellaneous
all A str NULL a list of all printers; (see ALL PRINTERS)
destinations D str NULL
names of printers that lpq/lprm should talk to find
a job that has been processed by a router script
(see README.routing)
forward_auth D str NULL
server to server authentication type, e.g. pgp, kerberos
force_localhost A bool TRUE
Forces the clients programs (lpr, lpc, etc.)
to send all print jobs and requests to the server running
on the localhost entry for action. This flag effectively
forces BSD LPR behaviour.
force_queuename A str NULL
See above.
logger_destination D str NULL
destination for logging information. Format is
host[%port][,(TCP|UDP)]
oh D str NULL Specific printcap entry for host. See above.
remote_support A str RMQC
if non-null, specifies allowed operations to remote queue.
R=lpr, M=lprm, Q=lpq, C=lpc
router D str NULL script that dynamically re-routes a job
(see README.routing)
server A bool false printcap entry for server only
server_auth_command D str NULL
authentication command for server to use.
tc A str NULL reference to a printcap entry to include as part of
the current entry.
use_auth D str NULL
client to server authentication type, e.g. pgp, kerberos
user_auth_command R str NULL
authentication command for user (client program)
FILTERS
By convention, all output filter names have the form Xf, where X is the
lower case letter corresponding to the lpr formatting option. The
filter option can specify a default filter for job files.
The of filter is started for each job and is used to print the banner
page and any FF separators between individual files of the job. It is
sent a special stop sequence by the lpd server, and must suspend
operations until sent a SIGCONT signal. A file or job filter is run
separately for each file; at the end of the job the of filter is
restarted and used to print the trailing banner (if any) and FF
separators.
Filters are invoked with a standard set of options defined by the
bk_filter_options (backwards compatible), bk_of_filter_options
(backwards compatible OF filter), and filter_options configuration
variables. See the lpd(8) manual page for details. If the first
characters of the filter specification are -$, i.e.- Xf=-$ filter, then
the command line options are not added. Currently, the options are:
bk_filter_options $P $w $l $x $y $F $c $L $i $J $C $0n $0h $-a
bk_of_filter_options $w $l $x $y
filter_options $C $F $H $J $L $P $Q $R $Z $a $c $d \
$e $f $h $i $j $k $l $n $s $w $x $y $-a
SPOOL QUEUES
Printcap entries which have a spool directory value (sd) are called
spool queues. Jobs sent to a printer with a spool queue are place in
the spool directory. When checking the spool queue for jobs, the
server will check to see if there is a printcap file in the directory
with the name printcap.host. If there is, the additional printcap
information is processed and used by the server.
If the spool directory is NFS exported, then remote hosts can
manipulate the spool entries directly; this can have catastrophic
effects, especially in systems where the NFS implementation has
defects. The printcap information is particularly vulnerable to
exploitation, as well as symbolic links, jobs which cannot be removed,
etc.
LOCAL PRINTERS
Local printers have an lp entry, which is the device that output should
be sent to, usually a serial port tty. PLP supplements this by using
the lp field to indicate a remote printer, or by allowing communication
with the printer using a separate program, known as an lp-pipe, instead
of a serial line. If the printcap lp entry contains a string of the
form printer@host, jobs are forwarded to the specified remote printer
on the host. If the printcap lp entry contains a string of the form |
command args , the command command is run, with the arguments args .
This can be used to communicate with printers connected to network
terminal servers, some TCP/IP-capable printers, and just about anything
you can hack up a communication program for. Read the LPRng Manual for
more details.
STTY OPTIONS
The stty printcap parameter recognizes a set of stty(1) options that
can be used to set serial line characteristics for the printer.
However, due to the differences between implementations of UNIX, there
are several sets of ty options supported. Invoke lpd(8) with the ‘‘-v’’
command-line option to see which set your installation is using.
Systems using the sgtty tty manipulation interface may use the
following stty(1) options:
bs0 bs1 [-]cbreak cooked cr0
cr1 cr2 cr3 [-]decctlq [-]echo
[-]even ff0 ff1 [-]lcase [-]litout
nl0 nl1 nl2 nl3 [-]nl
[-]noflsh new [-]nohang old [-]odd
[-]raw start stop tab0 tab1
tab2 [-]tabs [-]tandem tek ti700
[-]tilde tn300 tty33 tty37 vt05
[-]evenp [-]oddp [-]pass8
Systems using termio may use the following options:
[-]ignbrk [-]brkint [-]ignpar [-]parmrk [-]inpck
[-]istrip [-]inlcr [-]igncr [-]icrnl [-]iuclc
[-]ixon [-]ixany [-]ixoff [-]decctlq [-]tandem
[-]imaxbel [-]opost [-]olcuc [-]onlcr [-]ocrnl
[-]onocr [-]onlret [-]ofill [-]ofdel [-]cstopb
[-]cread [-]parenb [-]parodd [-]hupcl [-]clocal
[-]loblk [-]parity [-]evenp [-]oddp [-]stopb
[-]hup [-]crtscts [-]isig [-]noisig [-]icanon
[-]cbreak [-]xcase [-]echo [-]echoe [-]echok
[-]crterase [-]lfkc [-]echonl [-]noflsh [-]tostop
[-]echoctl [-]ctlecho [-]echoprt [-]prterase [-]echoke
[-]crtkill [-]lcase [-]nl [-]litout [-]pass8
[-]raw [-]sane [-]cooked [-]nopost fill
nl0 nl1 cr0 cr1 cr2
cr3 tab0 tab1 tab2 tab3
bs0 bs1 vt0 vt1 ff0
ff1 cs5 cs6 cs7 cs8
nul-fill del-fill -tabs
And systems using termios may use the following options:
[-]ignbrk [-]brkint [-]ignpar [-]parmrk [-]inpck
[-]istrip [-]inlcr [-]igncr [-]icrnl [-]iuclc
[-]ixon [-]ixany [-]ixoff [-]imaxbel [-]pass8
[-]opost [-]olcuc [-]onlcr [-]ocrnl [-]onocr
[-]onlret [-]ofill [-]ofdel [-]tabs nl0
nl1 cr0 cr1 cr2 cr3
tab0 tab1 tab2 tab3 bs0
bs1 vt0 vt1 ff0 ff1
cs5 cs6 cs7 cs8 [-]cstopb
[-]cread [-]parenb [-]parodd [-]hupcl [-]clocal
[-]crtscts [-]evenp [-]parity [-]oddp [-]pass8
[-]isig [-]icanon [-]xcase [-]echo [-]echoe
[-]echok [-]echonl [-]noflsh [-]tostop [-]iexten
[-]echoctl [-]ctlecho [-]echoprt [-]prterase [-]echoke
[-]crtkill [-]flusho [-]pendin
The fc , fs , xc , and xs printcap entries are obsolete, and if present
with non-zero values will abort print job processing.
INITIALIZATION
Many printers require an initialization string to be sent to them in
order to configure their operation. The leader (ld) and trailer (tr)
strings are sent at the start and end of job processing. These strings
are interpreted using the C language conventions for character
representation: \nnn is replaced with a character with the value nnn,
\n with a new line, \r with a carriage return, and so forth.
ALL PRINTERS
The LPRng software has the capability to use a remote database for
obtaining printcap and other information. One of the difficulties
arises when a list of all printers available is needed. By convention,
the special printer name all is reserved for this information; the all
field is a list of printers separated by spaces or punctuation. For
example:
#all printers
all:all=lp1,lp2,lp3,lp4
ACCOUNTING
Accounting in the LPRng package has evolved over time to accommodate
new requirements. The general approach is to use either a simple log
to file method in which the accounting information is written to a log
file or a more complex log to program method in which the accounting
information is written to a program. The information and method and
actions taken are specified by the following entries:
:as - start of job accounting
:ae - end of job accounting
:af - default job accounting
:achk - used accounting for authorization.
The value of the :as and :ae options are either a string which is used
as the accounting information or a program which is executed to log or
save the accounting information. If a program is executed then the
value of the :af entry is ignored and the program is run to record the
job accounting information. For example:
# string for information logging
:as=jobend $H $n $P $k $b $t
:ae=jobstart $H $n $P $k $b $t
:as=|/usr/local/libexec/logjobstart $H $n $P $k $b $t
:ae=|/usr/local/libexec/logjobend $H $n $P $k $b $t
If the :as or :ae value is a string then the :af information is used to
record the accounting information:
af=|/path - run program, :as or :ae written to
program STDIN
af=host%port - tcp/ip connection to port on host,
:as or :ae written to connection
af=path - treat path as a file pathname,
if file exists append :as or :ae
to file.
If the :achk flag is set then this is modified as follows.
If the :as entry specifies a program or :af entry specifies a
program or remote host (i.e. - logging using program) then
after accounting information has been written to the
program or connection a response will be read from the program
STDOUT or the connection.
This response is expected to be an ASCII string.
If the line is blank or starts with ACCEPT then the job will be printed,
HOLD will hold the job, REMOVE will remove the job,
and ABORT or a non-recognizable response will cause printing to be aborted.
If the output is written to a program then the exit status
of the program can be used as well.
If the program exits with nonzero status then the
exit code controls the disposition:
JHOLD, JREMOVE, and JABORT will hold, remove,
or abort the job respectively.
If the exit status is 0, then
the filter’s STDOUT will be read and processed as described above.
BOUNCE QUEUES AND PRINT FORMATS
If the lp option value has the format :lp=pr@host or job forwarding is
specified by :rp=pr:rm=host then the normal operation is simple to
store and forward the print jobs. If filters are specified then the
job files are first filtered and then the output of the filters is sent
to the destination. For historical reasons, a spool queue that does
filtering and forwarding is called a bounce queue. The
bounce_queue_format (default ’f’) specifies the output for the filtered
files. If this is not desirable the translate_format option can be
used to specify a format. The option has the form SdSdSdN, where S is
the original format and d is the final format. If none of the formats
match and there is an odd number of formats then the last one is used.
For example, pfmlf would convert formats p to f, m to l, and v to f.
The :lpd_bounce flag concatenate the output of the filters and the
result will be sent as a single job file to the destination. This
facility is useful when handling legacy print spooler applications that
do not understand the RFC1179 copy, etc., options. The first letter of
the bounce_queue_format (default ’f’) is used as the output file
format.
The lpr_bounce printcap flag can be used to cause LPR to do bounce
queue filtering in exactly the same manner as the server. This should
be used with caution as missing filters on the client system can cause
unexpected behavior.
KERBEROS, PGP, AND OTHER AUTHENTICATION METHODS
LPRng supports built in kerberos authentication. To enable this, the
LPD protocol has been extended to provide a way to transfer
authenticated and/or encrypted jobs and commands. The details are
covered in the LPRng HOWTO documentation.
Also, SSL can be used. See lprng_certs(1) for details.
FILES
The files used by LPRng are set by values in the printer configuration
file. The following are a commonly used set of default values.
//etc/lprng/lpd.conf LPRng configuration file
${HOME}/.printcap user printer description file
//etc/printcap printer description file
//etc/lprng/lpd.perms permissions
/var/run/lprng/lpd lock file for queue control
/var/spool/lpd spool directories
/var/spool/lpd/QUEUE/control queue control
/var/spool/lpd/QUEUE/log trace or debug log file
/var/spool/lpd/QUEUE/acct accounting file
/var/spool/lpd/QUEUE/status status file
SEE ALSO
lpd.conf(5), lpc(8), lpd(8), checkpc(8), lpr(1), lpq(1), lprm(1),
lpd.perms(5), pr(1), lprng_certs(1), lprng_index_certs(1).
AUTHOR
Patrick Powell <papowell@lprng.com>.
DIAGNOSTICS
Most of the diagnostics are self explanatory. If you are puzzled over
the exact cause of failure, set the debugging level on (-D5) and run
again. The debugging information will help you to pinpoint the exact
cause of failure.
HISTORY
LPRng is a enhanced printer spooler system with functionality similar
to the Berkeley LPR software. The LPRng developer mailing list is
lprng-devel@lists.sourceforge.net; subscribe by visiting
https://lists.sourceforge.net/lists/listinfo/lprng-devel or sending
mail to lprng-request@lists.sourceforge.net with the word subscribe in
the body.
The software is available via http://lprng.sourceforge.net