> And XKB is probably one of the most extensively documented protocols, I don't know what "extensively" means in your understanding, but the documentation of XKB is sloppily written. They even didn't labeled the items in "Appendix D: Protocol encoding". Which is the main document if one have to implement the protocol in code.
On Wed, 16 Feb 2022 09:59:55 +1000 Peter Hutterer <peter.hutte...@who-t.net> wrote: > On Tue, Feb 15, 2022 at 05:42:39PM +0200, John Found wrote: > > On Tue, 15 Feb 2022 14:29:05 +0000 > > Dave Howorth <x...@howorth.org.uk> wrote: > > > > > On Tue, 15 Feb 2022 15:21:07 +0200 > > > John Found <johnfo...@asm32.info> wrote: > > > > > > > What is the meaning of the fields in the following structure, > > > > in the XkbGetMap reply: > > > > > > > > KB_KEYSYMMAP 8+4n > > > > 4 LISTofCARD8 ktIndex ; What is this? > > > > 1 CARD8 groupInfo ; What is this? > > > > 1 CARD8 width ; Width of what? > > > > 2 n nSyms ; more or less clear > > > > 4n LISTofKEYSYM syms ; clear as well. > > > > > > Oh, and assuming you found this in the XKB Protocol Specification > > > then the answers to your question are in the same document, I > > > think. For example groupInfo is explained on p32. Just search the > > > document. > > > > Please, could you explain it on this example: > > > > 01 14 00 00 = ktIndex - what this means? > > 02 = groupInfo - what info? > > 04 = width - of what? > > 08 00 = 8 keysyms follow > > 34 00 00 00 = "4" > > 24 00 00 00 = "$" > > 00 00 00 00 = NULL > > 00 00 00 00 = NULL > > 34 00 00 00 = "4" > > 24 00 00 00 = "$" > > AC 20 00 00 = "€" (euro sign) > > AC 20 00 00 = "€" (euro sign) > > > > What the constants 0x01, 0x14 (ktIndex), 0x02 (groupInfo) and > > 0x04 (width) means? > > From: > https://www.x.org/releases/X11R7.7/doc/kbproto/xkbproto.html#XKB_Protocol_Requests > """ > Key Symbol Map > > The key symbol map for a key contains all of the information that a > client needs to process events generated by that key. Each key symbol > mapping reports: > > The number of groups of symbols bound to the key ( numGroups ). > The treatment of out-of-range groups ( groupInfo ). > The index of the key type to for each possible group ( > kt_index[MaxKbdGroups] ). The width of the widest type associated > with the key ( groupsWidth ). The two-dimensional (numGroups × > groupsWidth) array of symbols bound to the key. """ > > XKB is a huge spec and you will need to support virtually *all* of it > to get anywhere meaningful. Some terms that you don't know are > specific terms used in the protocol, e.g. if you do not know what > group "width" is that means you do not yet understand XKB well enough > to implement a protocol parser. > > And XKB is probably one of the most extensively documented protocols, > both originally and in terms of follow ups by people who had to wrap > their brains around it later. > > Which is also why I said earlier: you can either become an XKB expert > [1] or use libxkbcommon. XKB isn't *hard*, it's just complicated and > a lot to implement. > > Oh, and there's a PDF too https://www.x.org/docs/XKB/XKBproto.pdf in > case you want to inflict that on your ebook reader. > > Cheers, > Peter > > [1] fwiw, the job market for those is rather small and you rarely get > your face on TV during a crisis
