colour ("true" or "direct" colour). These consist of new entries (such
as "xterm-direct") which have a different setaf/setab implementation,
colors and pairs set to 0x1000000 and 0x10000, and a new RGB flag.
The setaf/setab definitions seem to be geared towards what ncurses (or
emacs maybe) needs, in that the new versions do only ANSI and RGB
colours (they can't be used for the 256 colour palette); they rely on
the silly ISO colon-separated version of SGR; and they use a weird
multiplication scheme so they still only need one argument. The higher
values of colors and pairs require a recent ncurses to parse.
tmux can use the RGB flag to detect RGB colour support (keeping the old
Tc extension for backwards compatibility for now). However, as we still
want to send 256 colour information unchanged when possible, the new
setaf/setab are awkward. So when RGB is present, reserve setaf/setab
only for ANSI colours and use the escape sequences directly for 256 and
RGB colours. (To my knowledge no recent terminal uses unusual escape
sequences for these in any case.)
it is present and zero. This is useful for users with terminals or fonts
that do not correctly support UTF-8 line drawing characters. GitHub
issue 927, reported by Hiroaki Yamazoe and Akinori Hattori.
wasting unnecessary space. The 'Tc' flag must be set in the external
TERM entry (using terminal-overrides or a custom terminfo entry), if not
tmux will map to the closest of the 256 or 16 colour palettes.
Mostly from Suraj N Kurapati, based on a diff originally by someone else.
entry:
F13-F24 are S-F1 to S-F12
F25-F36 are C-F1 to C-F12
F37-F48 are C-S-F1 to C-S-F12
F49-F60 are M-F1 to M-F12
and F61-F63 are M-S-F1 to M-S-F3
This should be no difference for applications inside tmux, but means
that any key binding for F13 will need to be replaced by S-F1 and so on.
the xterm escape sequence for the purpose (if xterm is configured to
allow it).
Written by and much discussed Ailin Nemui, guidance on
xterm/termcap/terminfo from Thomas Dickey.
terminals (I'm looking at you, putty) which disable the vt100 ACS mode
switching sequences in UTF-8 mode.
Also on terminals without ACS at all, use ASCII equivalents where
obvious.
on Sun consoles (TERM=sun or sun-color), even if there appear to still be
problems on some boxes (my Blade 100 is fine but edd's Blade 1000 shows odd
screen corruption).
Irritatingly, although op can be used to tell if a terminal supports default
colours, it can't be used to set them because in some terminfo descriptions it
resets attributes as a side-effect (acts as sgr0) and in others it doesn't, so
it is not possible to determine reliably what the terminal state will be
afterwards. So if AX is missing and op is present, tmux just sends sgr0.
Anyone using -d for a terminal who finds they actually needed it can replace it
using terminal-overrides, but please let me know as it is probably an omission
from terminfo.