XTMODKEYS — Modify keyboard reporting (CSI > Pp ; Pv m)

Byte forms

Every common string-literal form so you can paste-and-search either direction.

Description

The > prefix flips the m final byte from SGR (set-graphic-rendition) to XTMODKEYS — a runtime-mutable view of four xterm resources that control how modifier-laden keys are reported. The first parameter Pp selects the resource (0 = modifyKeyboard, 1 = modifyCursorKeys, 2 = modifyFunctionKeys, 3 = modifyKeypadKeys is reserved, 4 = modifyOtherKeys), and Pv sets its value. The killer feature is modifyOtherKeys (Pp=4): with Pv=0 xterm only reports Ctrl+letter as the corresponding C0 byte (Ctrl+I === Tab, Ctrl+M === Enter), with Pv=1 it reports modified versions of unambiguous keys via CSI 27 ~, and with Pv=2 it reports every modified printable key — letting editors like vim/emacs/kakoune distinguish Ctrl+I from Tab, Ctrl+H from Backspace, and bind Alt+letter without the legacy ESC-prefix hack. Reset by emitting \x1b[>Pp m with no Pv (restores xterm default) or \x1b[>4;0m to leave modifyOtherKeys mode. Kitty's CSI u keyboard protocol (separate sequence) offers a strictly richer alternative and is preferred for greenfield code; XTMODKEYS remains the de-facto compatibility path for the millions of TUIs already targeting xterm.

Spec citation: xterm-ctlseqs (XTMODKEYS)

Parameters

Examples

# Enable full modifyOtherKeys — every Ctrl+letter reports distinctly:\nprintf '\033[>4;2m'\n# (run from inside a TUI that handles CSI 27 ~ replies; raw shells will show garbage)

import sys\nsys.stdout.write('\x1b[>4;2m')   # enable modifyOtherKeys 2\n# remember to send '\x1b[>4;0m' on exit to restore default

fmt.Print("\x1b[>4;1m")   // modifyOtherKeys mode 1

process.stdout.write('\x1b[>4;2m')   // enable full modify-other-keys

printf("\x1b[>4;2m");   /* opt in to fully-modified key reports */\natexit_send("\x1b[>4;0m");  /* opt out at exit */

Terminal support

xterm

yes

Linux console (fbcon)

no

macOS Terminal.app

no

iTerm2

yes

Windows Terminal

yes

cmd.exe / ConPTY

no

kitty

yes

alacritty

yes

WezTerm

yes

Ghostty

yes

GNOME Terminal

partial

Konsole

yes

tmux

yes

GNU screen

yes

Related sequences

• DECSET ?1004 — Focus in/out events
• DECSET ?2004 — Bracketed paste mode
• C0 controls — BS, HT, LF, CR, BEL (single-byte codes)
• DECSTR — Soft terminal reset