OSC 555 Flash Screen
Flash the whole terminal briefly, foot's extension.
OSC 555 ST
- ECMA-48
- §8.3.89 OSC – Operating System Command, p. 51
- Specification
- foot-ctlseqs(7)
OSC 555 ST is foot’s: it flashes the whole terminal, laying a colored overlay over it for 50 milliseconds, the same overlay foot’s visual bell uses for 100. Its color comes from foot’s colors.flash and colors.flash-alpha settings, and anything after the number is ignored (foot-ctlseqs(7), osc.c). A program can use it to draw the eye without the bell; DECSCNM set and reset is the older way to flash a screen.
A default xterm has no OSC 555 and ignores it (the OSC numbers it knows). The cases follow xterm.
libghostty-vt does not recognize OSC 555 either: its OSC parser in osc.zig has no state for the number, so the string is dropped, and the cases pass.
Support
| Terminal | Version | Support | Notes |
|---|---|---|---|
| VT220 | manual, 2nd ed., 1984 | No | OSC is not among the controls it recognizes (§4.2) |
| VT510 | manual, 1st ed., 1993 | No | ignores an OSC string (chapter 4) |
| xterm | patch 412, xterm-411a | No | ignored |
| libghostty-vt | 83edd49 | No | ignored |
| Konsole | 26.11.70, a24c3d71 | No | not among the OSC numbers it handles (Vt102Emulation.h) |
| foot | 1.28.0 | Yes | a 50 ms overlay (foot-ctlseqs(7)) |
| ConEmu | build 230724, its documentation | No | not in its ANSI escape codes |
Validation
OSC555-1: Nothing on screen, and no bell
A
\e]555\e\\
B
|AB____|
cursor 1,3
bell 0
reply none