filter

filter(1)                   Easy Software Products                   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/postscript).

       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
            Processors (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://localhost:631/documentation.html

COPYRIGHT
       Copyright 1993-2004 by Easy Software Products, All Rights Reserved.



22 June 2000              Common UNIX Printing System                filter(1)