ncurses: init_color() has no effect (specific to PuTTY, xterm and gnome-terminal)
NCurses: Why does init_color return OK but still not set the color? (specific to xterm)
init_color is saving the color info in ncurses memory, and reporting success - but having no effect on the MacOS (Mojave 10.14.2) Terminal.app version 2.9.1 (421.1). ncurses was installed via HomeBrew:
$ brew info ncurses
ncurses: stable 6.1 (bottled) [keg-only]
Text-based UI library
https://www.gnu.org/software/ncurses/
/usr/local/Cellar/ncurses/6.1 (3,869 files, 8.3MB)
Poured from bottle on 2018-12-31 at 21:59:36
My workaround might have to be reliance on the default ncurses color palette.
Based on one of the answers in a prior question, I reviewed the terminfo source. The relevant section is under this text:
# The AppKit Terminal.app descriptions all have names beginning with
# "nsterm".
In particular:
# For Apple_Terminal v309+, use "nsterm-256color" (or "nsterm-bce")
It seems there's no specific section for 10.14; the latest entry is for 10.13:
# reviewed Terminal.app in High Sierra (version 2.8 build 400) -TD
# Comparing with build361, little has changed, except that italics work.
# Direct-color is not supported, by the way.
#
# Improved rmso/rmul -TD
nsterm-build400|Terminal.app in OS X 10.13,
rmso=\E[27m, rmul=\E[24m, use=xterm+sm+1006,
use=ecma+italics, use=nsterm-build361,
# This is an alias which should always point to the "current" version
nsterm|nsterm-256color|Apple_Terminal|AppKit Terminal.app,
use=nsterm-build400,
Upon reading that I'm unclear on whether this is expected behaviour.
When I run this, all asserts pass, but the default colours (rather than the edited colours) are shown for the foreground and background.
#include <assert.h>
#include <fcntl.h>
#include <ncursesw/ncurses.h>
#include <unistd.h>
int main() {
int fdump = open("/tmp/ncurses_dump", O_WRONLY|O_CREAT|O_TRUNC, 0600);
dup2(fdump, STDOUT_FILENO);
assert(initscr() != NULL);
assert(ERR != start_color());
assert(has_colors());
assert(can_change_color());
assert(COLOR_PAIRS >= 256);
assert(COLORS >= 256);
// color 21 is blue by default
// let's make it white
const NCURSES_COLOR_T fore = 21;
assert(ERR != init_color(fore, 998, 999, 1000));
NCURSES_COLOR_T r, g, b;
assert(ERR != color_content(fore, &r, &g, &b));
assert(r == 998);
assert(g == 999);
assert(b == 1000);
// color 195 is light blue by default
// let's make it black
const NCURSES_COLOR_T back = 195;
assert(ERR != init_color(back, 0, 1, 2));
assert(ERR != color_content(back, &r, &g, &b));
assert(r == 0);
assert(g == 1);
assert(b == 2);
// arbitrary
const NCURSES_PAIRS_T pair = 100;
assert(ERR != init_pair(pair, fore, back));
NCURSES_COLOR_T fc, bc;
assert(ERR != pair_content(pair, &fc, &bc));
assert(fc == fore);
assert(bc == back);
// The pair init works, but the color init doesn't - this still outputs blue
// on light blue
assert(ERR != attron(COLOR_PAIR(pair)));
assert(ERR != addch('X'));
while (getch() != 'q');
endwin();
return 0;
}
The dump file then contains the following:
$ hexdump -C /tmp/ncurses_dump
00000000 1b 5b 3f 31 30 34 39 68 1b 5b 32 32 3b 30 3b 30 |.[?1049h.[22;0;0|
00000010 74 1b 5b 31 3b 34 37 72 1b 28 42 1b 5b 6d 1b 5b |t.[1;47r.(B.[m.[|
00000020 34 6c 1b 5b 3f 37 68 1b 5b 33 39 3b 34 39 6d 1b |4l.[?7h.[39;49m.|
00000030 5d 34 3b 32 31 3b 72 67 62 3a 46 45 2f 46 45 2f |]4;21;rgb:FE/FE/|
00000040 46 46 1b 5c 1b 5d 34 3b 31 39 35 3b 72 67 62 3a |FF.\.]4;195;rgb:|
00000050 30 30 2f 30 30 2f 30 30 1b 5c 1b 5b 33 39 3b 34 |00/00/00.\.[39;4|
00000060 39 6d 1b 5b 33 37 6d 1b 5b 34 30 6d 1b 5b 48 1b |9m.[37m.[40m.[H.|
00000070 5b 32 4a 1b 5b 33 38 3b 35 3b 32 31 6d 1b 5b 34 |[2J.[38;5;21m.[4|
00000080 38 3b 35 3b 31 39 35 6d 58 1b 28 42 1b 5b 6d 1b |8;5;195mX.(B.[m.|
00000090 5b 33 39 3b 34 39 6d 1b 5b 33 37 6d 1b 5b 34 30 |[39;49m.[37m.[40|
000000a0 6d 1b 5b 33 38 3b 35 3b 32 31 6d 1b 5b 34 38 3b |m.[38;5;21m.[48;|
000000b0 35 3b 31 39 35 6d 71 1b 28 42 1b 5b 6d 1b 5b 33 |5;195mq.(B.[m.[3|
000000c0 39 3b 34 39 6d 1b 5b 33 37 6d 1b 5b 34 30 6d 1b |9;49m.[37m.[40m.|
000000d0 5b 33 39 3b 34 39 6d 0d 1b 5b 34 37 64 1b 5b 4b |[39;49m..[47d.[K|
000000e0 1b 5b 33 39 3b 34 39 6d 1b 5d 31 30 34 07 1b 5b |.[39;49m.]104..[|
000000f0 34 37 3b 31 48 1b 5b 3f 31 30 34 39 6c 1b 5b 32 |47;1H.[?1049l.[2|
00000100 33 3b 30 3b 30 74 0d 1b 5b 3f 31 6c 1b 3e |3;0;0t..[?1l.>|
0000010e
From the comments, you would need a terminfo entry (source) like this to use the new functionality in Mohave:
nsterm-direct|nsterm with direct color,
use=xterm+indirect, use=nsterm,
Compile/install using the ncurses 6.1 tic which you installed with brew.
That's a starting point (Apple does make incompatible changes, as you might notice in the history of the nsterm entries). There are other details to investigate by testing (see tack and vttest for instance).
However: init_color is not much use in this scenario (i.e., direct colors), since it assumes you can reprogram the color-content of an RGB entry. You can't. What you can do is use init_extended_pair as shown in the picsmap example. Some people might find that useful (see discussion). A color pair only affects the data in ncurses; color content changes the terminal.
For 256 colors... Terminal.app doesn't have a changeable palette unless that was done recently. That's why nsterm-256color uses xterm+256setaf as a building block (it's a have-not in this realm). If you follow the links back to the definition, you will see this:
# palette is hardcoded...
xterm+256setaf|xterm 256-color (set-only),
ccc@,
colors#0x100, pairs#0x10000,
initc@, op=\E[39;49m,
setab=\E[%?%p1%{8}%<%t4%p1%d%e%p1%{16}%<%t10%p1%{8}%-%d%e48;
5;%p1%d%;m,
setaf=\E[%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5
;%p1%d%;m,
setb@, setf@,