LPFILTER(ADM) UNIX System V
Name
lpfilter - administer filters used with the print service
Syntax
/usr/lib/lpfilter -f filter-name -F path-name
/usr/lib/lpfilter -f filter-name -
/usr/lib/lpfilter -f filter-name -i
/usr/lib/lpfilter -f filter-name -x
/usr/lib/lpfilter -f filter-name -l
Description
The lpfilter command is used to add, change, delete, and
list filters used with the LP print service. These filters
are used to convert the content type of a file to a content
type acceptable to a given printer. One of the following
options must be used with the lpfilter command: -F path-
name (or - for standard input) to add or change a filter, -i
to reset an original LP print service filter to its factory
setting, -x to delete a filter, or -l to list a filter
description.
The argument all can be used instead of a filter-name with
any of these options. When all is specified with the -F or
- option, the requested change is made to all filters.
Using all with the -i option has the effect of restoring to
their original settings all filters for which predefined
settings were initially available. Using the all argument
with the -l option produces a list of all filters, and using
it with the -x option results in all filters being deleted.
Adding or Changing a Filter
The filter named in the -f option and described in the input
is added to the filter table. If the filter already exists,
its description is changed to reflect the new information in
the input. Once added, a filter is available for use.
The filter description is taken from the path-name if the -F
option is given or from the standard input if the - option
is given. One of the two must be given to define or change
a filter. If the filter named is one originally delivered
with the LP print service, the -i option will restore the
original filter description.
Filters are used to convert the content of a request into a
data stream acceptable to a printer. For a given print
request, the LP print service will know the following:
⊕ the type of content in the request
⊕ the name of the printer
⊕ the type of the printer
⊕ the types of content acceptable to the printer
⊕ the modes of printing asked for by the originator of
the request
It will use this information to find a filter that will
convert the content into a type acceptable to the printer.
Below is a list of items that provide input to this command
and descriptions of each item. All lists are separated by
commas or spaces.
Input types: content-type-list
Output types: content-type-list
Printer types: printer-type-list
Printers: printer-list
Filter type: filter-type
Command: shell-command
Options: template-list
Input types
This gives the types of content that can be accepted by the
filter.
Output types
This gives the types of content that the filter can produce
from any of the input content types.
Printer types
This gives the type of printers for which the filter can be
used. The LP print service will restrict the use of the
filter to these types of printers.
Printers
This gives the names of the printers for which the filter
can be used. The LP print service will restrict the use of
the filter to just the printers named.
Filter type
This marks the filter as a ``slow'' filter or a ``fast''
filter. Slow filters are generally those that take a long
time to convert their input. They are run unconnected to a
printer to keep the printers from being tied up while the
filter is running. Fast filters are generally those that
convert their input quickly or those that must be connected
to the printer when run. These will be given to the
interface program to run connected to the physical printer.
Command
This specifies the program to run to invoke the filter. The
program name as well as fixed options are included in the
shell-command; additional options are constructed, based on
the characteristics of each print request and on the Options
field.
The command must accept a data stream as standard input and
produce the converted data stream on its standard output.
This allows filter pipelines to be constructed to convert
data not handled by a single filter.
Options
This is a list of templates separated by commas used by the
LP print service to construct options to the filter from the
characteristics of each print request listed in the table
later. In general, each template is of the following form:
keyword pattern = replacement
The keyword names the characteristic that the template
attempts to map into a filter-specific option; each valid
keyword is listed in the table below. A pattern is either a
literal pattern of one of the forms listed in the table or a
single asterisk, *; if the pattern matches the value of the
characteristic, the template fits and is used to generate a
filter-specific option. A pattern of * matches any value.
The replacement is a string used as a filter-specific option
with an embedded asterisk, *, replaced with the value of the
characteristic.
_________________________________________________________________
| lp Option Characteristic keyword Possible |
| |
|________________________________________________________________|
| -T Content type (input) INPUT content-type|
| N/A Content type (output) OUTPUT content-type|
| N/A Printer type TERM printer-type|
| -f, -o cpi= Character pitch CPI integer |
| -f, -o lpi= Line pitch LPI integer |
| -f, -o length= Page length LENGTH integer |
| -f, -o width= Page width WIDTH integer |
| -P Pages to print PAGES page-list |
| -S Character set/ CHARSET character- |
| print wheel set-name/ |
| print- |
| wheel-name |
| -f Form name FORM form-name |
| -y Modes MODES mode |
| -n Number of copies COPIES integer |
|________________________________________________________________|
For example, the template
MODES landscape = -l
would show that if a print request includes the -y landscape
option, the filter should be given the option -l. As
another example, the template
TERM * = -T *
would show that the filter should be given the option -T
printer-type for whichever printer-type is associated with a
print request using the filter.
When an existing filter is changed with this command, items
that are not specified in the new information are left as
they were. When a new filter is added with this command,
unspecified items are given default values.
Note that a filter name and a command must be given. A
filter with no input type value is assumed to work with any
input type; this is also true for the output type, printer
type, and printer values.
Deleting a Filter
The -x option is used to delete the filter specified in
filter-name from the LP filter table.
Listing a Filter Description
The -l option is used to list the description of the filter
named in filter-name. If the command is successful, the
following message is sent to standard output:
Input types: content-type-list
Output types: content-type-list
Printer types: printer-type-list
Printers: printer-list
Filter type: filter-type
Command: shell-command
Options: template-list
If the command fails, an error message is sent to standard
error.
See Also
lpadmin(ADM), lp(C)
Authorization
The use of this utility is governed by assignment of the lp
authorization, which is usually reserved for system
administrators.
(printed 3/2/90) LPFILTER(ADM)