TERM=alacritty, TERM=tmux and TERM=tmux-256color don't handle Shift+F<N>.

[slyfox]

alacritty (​https://github.com/alacritty/alacritty) is an xterm-compatible terminal. Note how small the diff is (no diffs around kf* entries):

$ infocmp -a1 xterm alacritty
comparing xterm to alacritty.
    comparing booleans.
        ccc: F:T.
        hs: F:T.
        km: T:F.
    comparing numbers.
        colors: 8, 256.
        pairs: 64, 65536.
    comparing strings.
        dsl: NULL, '\E]2;\007'.
        fsl: NULL, '^G'.
        initc: NULL, '\E]4;%p1%d;rgb\:%p2%{255}%*%{1000}%/%2.2X/%p3%{255}%*%{1000}%/%2.2X/%p4%{255}%*%{1000}%/%2.2X\E\\'.
        ka1: '\EOw', NULL.
        ka3: '\EOy', NULL.
        kb2: '\EOu', '\EOE'.
        kbs: '^H', '^?'.
        kc1: '\EOq', NULL.
        kc3: '\EOs', NULL.
        mgc: '\E[?69l', NULL.
        oc: NULL, '\E]104\007'.
        rs1: '\Ec', '\Ec\E]104\007'.
        setab: '\E[4%p1%dm', '\E[%?%p1%{8}%<%t4%p1%d%e%p1%{16}%<%t10%p1%{8}%-%d%e48;5;%p1%d%;m'.
        setaf: '\E[3%p1%dm', '\E[%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p1%d%;m'.
        setb: '\E[4%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m', NULL.
        setf: '\E[3%?%p1%{1}%=%t4%e%p1%{3}%=%t6%e%p1%{4}%=%t1%e%p1%{6}%=%t3%e%p1%d%;m', NULL.
        smglr: '\E[?69h\E[%i%p1%d;%p2%ds', NULL.
        tsl: NULL, '\E]2;'.
        Se: '\E[2 q', '\E[0 q'.
        TS: NULL, '\E]2;'.
        ka2: '\EOx', NULL.
        kb1: '\EOt', NULL.
        kb3: '\EOv', NULL.
        kc2: '\EOr', NULL.
        kp5: '\EOE', NULL.
        kpADD: '\EOk', NULL.
        kpCMA: '\EOl', NULL.
        kpDIV: '\EOo', NULL.
        kpDOT: '\EOn', NULL.
        kpMUL: '\EOj', NULL.
        kpSUB: '\EOm', NULL.
        kpZRO: '\EOp', NULL.

tmux is a screen-compatible wrapper. infocmp -a1 screen-256color tmux-256color is a bit bigger. I'll omit it.

All of the melow fails on ncurses-6.2:

# in alacritty
$ TERM=alacritty mc
< press Shift-F6 to rename a directory>
< got: F8 response >

# in tmux in xterm
$ TERM=tmux mc
< press Shift-F6 to rename a directory>
< got: F8 response >

# in tmux in xterm
$ TERM=tmux-256color mc
< press Shift-F6 to rename a directory>
< got: F8 response >

I think xterm and screen only work because mc hardcodes terminal names in misc/mc.lib:

...
[terminal:xterm]
...
f16=\\e[29~;\\e[17\;2~
...

[terminal:gnome]
copy=xterm

[terminal:rxvt]
copy=xterm

[terminal:xterm-new]
copy=xterm

[terminal:xterm-color]
copy=xterm

[terminal:xterm-256color]
copy=xterm

[terminal:screen]
copy=xterm

[terminal:screen-256color]
copy=xterm
...

We can hardcode a few more $TERM names, but it does not scale very well and is not compatible to user-defined terminal definitions if they chose to do it.

WDYT of making feature detection based only on terminfo capabilities if those are sufficient?

$ LANGUAGE=en mc --version
GNU Midnight Commander 4.8.25
Built with GLib 2.64.5
Built with S-Lang 2.3.2 with terminfo database
With builtin Editor and Aspell support
With subshell support as default
With support for background operations
With mouse support on xterm
With support for X11 events
With internationalization support
With multiple codepages support
With ext2fs attributes support
Virtual File Systems:
 cpiofs, tarfs, sfs, extfs, ext2undelfs, ftpfs, sftpfs, fish, smbfs
Data types:
 char: 8; int: 32; long: 64; void *: 64; size_t: 64; off_t: 64;

[andrew_b]

Replying to slyfox:

WDYT of making feature detection based only on terminfo capabilities if those are sufficient?

There is a risk to broke the mc tty layer. Personally I'm not ready to do that.

[andrew_b]

Related tickets: #1769, #1890, #3254.

[slyfox]

0001-Ticket-4149-add-alacritty-tmux-tmux-256color-as-xter.patch

[slyfox]

0001-Ticket-4149-add-alacritty-tmux-tmux-256color-as-xter.patch adds alacritty, tmux, and tmux-256color as aliases of xterm.

[ossi]

There is a risk to broke the mc tty layer. Personally I'm not ready to do that.

nah, some minor temporary regressions seem like a perfectly acceptable price to pay for that.

[andrew_b]

Replying to ossi:

There is a risk to break the mc tty layer. Personally I'm not ready to do that.

nah, some minor temporary regressions seem like a perfectly acceptable price to pay for that.

Patches are welcome!

[andrew_b]

Branch: 4149_more_terminals
changeset:4059873ef424ce981bdccde572a5a613925cdc8b

[andrew_b]

Merged to master: [08dd7db86a71050b2e7e31dba3406bd9b021c975].