Re: IPP under emacs [was: Re: Post-22.1 development?]

[Vinicius Jose Latorre]

Richard Stallman wrote:
>     Some time ago, Eric Marsden created the ipp.el package, see the links:
>
> What does this do?
>   

;; The Internet Printing Protocol is intended to replace the LPD
;; protocol for interacting with network printers. It specifies
;; mechanisms for querying the capabilities of a printer, submitting
;; and cancelling jobs, and queue monitoring.
;;
;; You can find out whether a device is IPP-capable by trying to
;; telnet to port 631. If it accepts the connection it probably
;; understands IPP. You then need to discover the path component of
;; the URI, for example by reading the documentation or from a driver
;; program. Tested or reported to work on the following devices:
;;
;;   * Tektronix Phaser 750, with an URI of the form ipp://host:631/
;;     (empty path component)
;;
;;   * HP Laserjet 4000, with a path component of /ipp/port1.
;;
;;   * Xerox Document Centre 460 ST, with empty path component.
;;
;;   * CUPS printer spooler (see <URL:http://www.cups.org/>).
;;
;;
;;
;; Usage: load this package by putting in your ~/.emacs.el
;;
;;    (require 'ipp)
;;
;; then try printing a file using 'M-x ipp-print'. This will prompt
;; you for a file name (which should be in a format understood by the
;; printer, such as Postscript), and the URI of the printer. There are
;; also two functions for querying the capability of the device
;; `ipp-get-attributes' and examining its queue `ipp-get-jobs'. Until
;; I write display code for these functions you will have to call them
;; from the *scratch* buffer with C-j to examine their return value.
;;
;;
;; The IPP network protocol is based on HTTP/1.1 POST requests, using
;; a special "application/ipp" MIME Content-Type. The data is encoded
;; using simple marshalling rules.
;;
;; The Internet Printing Protocol is described in a number of RFCs:
;;   <URL:http://www.faqs.org/rfcs/rfc2565.html>
;;   <URL:http://www.faqs.org/rfcs/rfc2566.html>
;;   <URL:http://www.faqs.org/rfcs/rfc2568.html>
;;
;; and the Printer Working Group maintain a page at
;;
;;   <URL:http://www.pwg.org/ipp/>
;;
;;
;; Eventually it would be nice to modify the Emacs printing API to
;; support this type of direct printing, so that a user could set
;; `ps-printer-name' to "ipp://modern-printer:631/" or
;; "lpd://ancient-printer/queue" (it would be easy to write a package
;; similar to this one implementing the LPD protocol at the network
;; level; the LDP protocol is very simple).