[Xorg] Revision of Appendix A of the X11 Protocol Spec: KEYSYM Encoding

[Markus Kuhn]

I have substantially revised and updated the long neglected KEYSYM
Encoding specification in Appendix A of the X11 Protocol Standard. The
result, which I propose for inclusion into the next X.Org release,
is on

  http://www.cl.cam.ac.uk/~mgk25/ucs/X11.keysyms.pdf

The troff source to replace xc/doc/specs/XProtocol/X11.keysyms is on

  http://www.cl.cam.ac.uk/~mgk25/ucs/X11.keysyms       

Changes in a nutshell:

  - Added definition of Unicode-mapped keysyms 0x01000100 to 0x0110ffff

  - Restructuring of text, with separate sections for

      - Special keysyms
      - Latin-1 keysyms
      - Unicode keysyms
      - Function keysyms
      - Vendor keysyms
      - Legacy keysyms

  - Addition of Unicode cross-reference column to Legacy keysym table

  - Added some words on long-term depreciation of some of the Legacy
    keysyms (Currency, Special, etc.).

  - Addition of the 0xFExx keysyms (Keyboard (XKB) Extention) from
    <X11/keysymdef.h>, which were missing so far completely from the
    standard.

  - Replaced the archaic ISO/ECMA 16/16 notation with more useful
    contemporary hexadecimal numbers

  - Updated the character names to latest edition of ISO 8859 (which now uses
    the ISO 10646 names)

  - Removed some long obsolete and irrelevant text (e.g. the section sign vs.
    paragraph sign vs. pilcrow naming discussion), and rephrased other parts
    to give more modern examples.

  - Added keysyms

      0x06ad   Ukrainian_ghe_with_upturn
      0x06bd   Ukrainian_GHE_WITH_UPTURN
      0xfe60   dead_belowdot
      0xfe61   dead_hook
      0xfe62   dead_horn

   from Xfree86 <X11/keysymdef.h>.

Still to do:

  - Investigate the semantics of the added "Keyboard (XKB) Extention"
    set.

    E.g., some of these seem to come from ISO 9995-7, but cross-referencing
    with that document did not give a flawless match. Any additional
    information on that topic are highly welcome. Who did add the
    "Keyboard (XKB) Extention" keysyms, and when. Is there any additional
    background documentation about the meaning of these keysyms? Are they
    all actually used and needed?

  - Look at Microsoft's recent Multimedia/Internet function keys, which are
    in part already covered in XFree86 vendor extensions, whether/how these
    should be moved into the X11 standard.

A matching updated keysymdef.h proposal is on

  http://www.cl.cam.ac.uk/~mgk25/ucs/keysymdef.h

Comments and reviews welcome!

Markus

-- 
Markus Kuhn, Computer Laboratory, University of Cambridge
http://www.cl.cam.ac.uk/~mgk25/ || CB3 0FD, Great Britain