drmikehenry
commented
4 years ago Vim support for key codes can be spotty. In :help terminal-key-codes there is a (partial) list of key codes that can be configured using the set command. Function keys that are completely unmodified are supported (<F12>, for example), as are shifted function keys (<S-F12>); but function keys with the control modifier aren't supported. As shown in :help xterm-modifier-keys, Vim tries to avoid defining all combinations of modifiers for all keys, and instead uses a special sequence (;*X) at the end of the corresponding unmodified key.
For Xterm on my Linux system, the default key code for <F12> is shown as follows:
set <F12>This displays as:
^[[24;*~The first two characters (^[) are shown in a different color, indicating that they represent pressing control with [; this is another name for the Escape character. Note the extra ;*~ at the end of the sequence. This means that Xterm uses <Escape>[24~ for the unmodified key, and that modifiers will extend this sequence based on the particular modifier. For the shift modifier, the result is <Escape>[24;2~ (there is an extra ;2 inserted before the final character of the key code).
For key codes that Vim supports directly using the :set command, teaching Vim how to recognize a key code is mostly straightforward. As an example, make the following two mappings to make it easy to see when <F5> and <F6> are pressed:
:map <F5> :echo '<F5>'<CR>
:map <F6> :echo '<F6>'<CR>Now pressing <F5> or <F6> should echo the key name.
Typing :set <F5> yields ^[[15;*~, and :set <F6> yields ^[[17;*~. For demonstration purposes, these codes may be swapped as follows:
:execute "set <F5>=\e[17;*~"
:execute "set <F6>=\e[15;*~"Note the use of execute above. This is just for the convenience of using double-quoted strings that expand the two characters \e into the Escape code, rather than having to enter the actual key code directly (by pressing CTRL-v Escape, for example).
You should be able to do the same thing on your Mac, adjusting for whatever key codes these keys produce.
Things get harder for keys whose key codes aren't directly supported with :set. Function keys using the control modifier fall in this category, so it's not possible to do :set <C-F12>. This is despite the fact that the syntax <C-F12> is valid within mappings, because mappings and key codes are two different things to Vim.
The hack I use in Fixkey is to find a key that isn't used on typical keyboards, change the key code for that key, and then map that key to the unsupported key. For historical reasons, Vim supports numbered function keys beyond <F12>. The keys <F13> through <F-37> known to Vim, along with their shifted counterparts. Modern keyboards lack these keys, so Fixkey uses them as described above.
For your case, you might be able to make <C-F12> work by setting the key code for <F13> to be your sequence ^[[24^, and then map <F13> to <C-F12>:
:execute "set <F13>=\e[24^"
:map <F13> <C-F12>
:map! <F13> <C-F12>As before, execute allows the use of \e for Escape. The :map and :map! combination ensures mapping in all of Vim's modes. Within Fixkey itself, the function Fixkey_setNewKey() allocates a spare key from the range of unused function keys, sets the desired key code using :set, then performs the two mappings as shown above.
boulderob
hello. i came here via a stack post. i'm using vim8 on mac sierra. i'm trying to get it to recognize but it doesn't recognize that combo with the modifier key Ctl.
i can see that this combo produces
^[[24^in my stock terminal and in insert mode in vim. i can also see that the mac terminal is generating that key sequence in it's own profile config.instead of installing and using your plugin which is overkill for the one key seq i want to configure for vim, i want to borrow from it and just use the one line i need which is this (btw i believe you documented this in your stack post as well)
the problem is when i try to use this incantation, vim doesn't recognize the line as a valid line because it thinks it's an invalid option no matter how many different ways i've tried to enter it.
it obviously is tripping up on the fact that
<C-F12>doesn't look like a known vim option and i would agree but your entire plugin is based on it working! :) i'm probably missing something really simple.any and all thoughts greatly appreciated thx