filter(1)

NAME

       filter - cups file conversion filter interfaces

SYNOPSIS

       filter job user title num-copies options [ filename ]

DESCRIPTION

       The CUPS filter interface provides a standard method for adding support
       for new document types to CUPS. Each filter is  capable  of  converting
       from  one  or  more  input formats to another format that can either be
       printed directly or piped into another filter to get it to a  printable
       format.

       Filters  must be capable of reading from a filename on the command-line
       or from the standard input, copying the standard input to  a  temporary
       file  as  required  by  the file format. All output must be sent to the
       standard output.

       The command name (argv[0]) is  set  to  the  name  of  the  destination
       printer.

ENVIRONMENT VARIABLES

       The following environment variables are defined by the CUPS server when
       executing each filter:

       CHARSET
            The default text character set (typically us-ascii or iso-8859-1).

       CLASS
            When  a  job is submitted to a printer class, contains the name of
            the destination printer class. Otherwise this environment variable
            will not be set.

       CONTENT_TYPE
            The  MIME  type  associated  with the file (e.g. application/post-
            script).

       CUPS_DATADIR
            The directory where data files can be found.

       CUPS_SERVERROOT
            The root directory of the server.

       DEVICE_URI
            The device-uri associated with the printer.

       LANG
            The default language locale (typically C or en).

       PATH
            The standard execution path for external programs that may be  run
            by the filter.

       PPD
            The full pathname of the PostScript Printer Description (PPD) file
            for this printer.

       PRINTER
            The name of the printer; this is provided for shell scripts  which
            may not be able to get the passed argv[0] string.

       RIP_CACHE
            The  recommended  amount of memory to use for Raster Image Proces-
            sors (RIPs).

       SOFTWARE
            The name and version number of the server (typically CUPS/1.1).

       TZ
            The timezone of the server.

       USER
            The  user  executing  the  filter,  typically  lp;   consult   the
            cupsd.conf file for the current setting.

COMPATIBILITY

       While  the  filter  interface  is  compatible  with  System V interface
       scripts, it will only work with the System V interface  script  as  the
       only  filter.   Typically the interface script will be provided via the
       lpadmin(8) command using the -i option.

SEE ALSO

       backend(1), cupsd(8), CUPS Interface Design Description, CUPS  Software
       Administrators  Manual, CUPS Software Programmers Manual, http://local-
       host:631/documentation.html

COPYRIGHT

       Copyright 1993-2005 by Easy Software Products, All Rights Reserved.

22 June 2000              Common UNIX Printing System                filter(1)