DCS Sequences

Device Control String — ESC P (or the 8-bit 0x90) followed by parameters, an intermediate/final selector, a string payload, and a string terminator. DCS frames carry longer, structured payloads than CSI or OSC: sixel images, terminfo queries, and the DECRQSS setting queries.

Structure

ESC P <params> <selector> <payload> ST

• selector: intermediate + final bytes identifying the function (e.g. $ q for DECRQSS)
• payload: function-specific data
• ST: string terminator — ESC \ (preferred) or 0x9C

Otty support

vte does not dispatch general DCS payloads, so most DCS-framed functions are inert. Otty scans the byte stream for the ones it answers:

• DECRQSS cursor-style query (DCS $ q SP q ST) — replied with the current cursor code. See below.
• XTVERSION reply — Otty emits DCS > | otty(<version>) ST in response to the CSI > q request (so nvim / kakoune can gate features).

Sixel graphics and XTGETTCAP (DCS + q) are not supported.

Detail pages

• DECRQSS — Request Selection or Setting