backend(1)

NAME
       backend - cups backend transmission interfaces

SYNOPSIS
       backend job user title num-copies options [ filename ]

DESCRIPTION
       The  CUPS backend interface provides a standard method for
       sending document files to different physical interfaces.

       Backends must be capable of reading from a filename on the
       command-line or from the standard input, copying the stan-
       dard input to a temporary file if required by the physical
       interface.

       The command name (argv[0]) is set to the device URI of the
       destination  printer.  Starting  with  CUPS  1.1.22,   any
       authentication  information in argv[0] will be removed, so
       backend developers are urged to use the  DEVICE_URI  envi-
       ronment  variable  whenever  authentication information is
       required.

ENVIRONMENT VARIABLES
       The following environment variables  are  defined  by  the
       CUPS server when executing the backend:

       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. applica-
            tion/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; this is
            provided for shell scripts which may not be  able  to
            get  the  passed argv[0] string and for backends that
            require any authentication information which  is  not
            included in argv[0].

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



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backend(1)            Easy Software Products           backend(1)


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

       PPD
            The full pathname of the PostScript Printer  Descrip-
            tion (PPD) file for this printer.

       PRINTER
            The name of the printer.

       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 backend, typically root; con-
            sult the cupsd.conf file for the current setting.

SEE ALSO
       cupsd(8), filter(1)  CUPS  Interface  Design  Description,
       CUPS  Software  Administrators  Manual, CUPS Software Pro-
       grammers Manual, http://localhost:631/documentation.html

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























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