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 standard 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.
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. 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; this is provided for shell scripts which may not be able to get the passed argv[0] string.
LANG
The default language locale (typically C or en).
PATH
The standard execution path for external programs that may be run by the backend.
PPD
The full pathname of the PostScript Printer Description (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; consult the cupsd.conf file for the current setting.
