Standards and specifications¶

Every claim on TDN traces to one of a small number of documents. This page catalogs them in the order the rest of the site follows: the framework standards that define the byte grammar, the DEC manuals that define most of the commands, xterm's document that defines most of the rest, and the vendor and working-group documents that define modern extensions. Each entry says what the document is authoritative for and which TDN section derives from it.

Framework standards¶

Document	Defines	TDN sections
ECMA-35 / ISO 2022	Code structure: C0/C1 sets, G0–G3 designation and invocation, 7-bit vs 8-bit environments, the `ESC` intermediate/final byte grammar	Control characters and ESC, Encoding
ECMA-48 / ISO 6429 / ANSI X3.64	Control functions: CSI parameter/intermediate/final grammar, the standard final bytes (CUP, ED, SGR, SM/RM…), the OSC/DCS/APC/PM/SOS string framing, `ST`	CSI, OSC anatomy, DCS
ECMA-6 / ISO 646	The 7-bit graphic set that ASCII and the national variants are instances of	Encoding
ISO/IEC 10646 / Unicode	The character repertoire; UTF-8	Text
UAX #11 East Asian Width	The `W`/`F`/`A` properties that terminal column width is derived from	Character width
UAX #29 Text Segmentation	Extended grapheme cluster boundaries	Grapheme clusters
UTS #51 Emoji	Presentation selectors and ZWJ sequences that widen or join cells	Character width, Grapheme clusters

ECMA-48 defines a grammar and a set of functions, not a terminal. It does not say what a screen is, has no notion of scrollback, private modes, or mouse reporting, and reserves the p–~ final bytes and the <, =, >, ? parameter prefixes for private use. Almost everything a modern application relies on lives in that private space.

DEC¶

Document	Defines	TDN sections
VT100 User Guide	The baseline: DECSC/DECRC, DECSTBM, the first private modes (`?1`–`?8`), DECALN, the original DA reply	Cursor, Scrolling, Modes
VT220 Programmer Reference	8-bit controls and S7C1T/S8C1T, DECSCA and selective erase, DECUDK, secondary DA, the `~`-terminated function-key encoding	Escape, Erase, DCS, Legacy keyboard
VT320, VT420	DECRQM/DECRPM, DECRQSS/DECRPSS, DECSLRM and DECLRMM, DECSCUSR (VT520), tertiary DA	Modes, DECRQSS, Scrolling
VT330/VT340	Sixel and ReGIS	Sixel, ReGIS
VT510/VT520	The most complete single DEC reference; the manual TDN cites when a command's DEC definition is needed	throughout
DEC STD 070 Video Systems Reference Manual	DEC's internal conformance standard: the parser, the `DCS P* I* Ft data ST` header and the equivalent OSC/APC/PM structure, private-range rules	Control strings, DCS, OSC anatomy

The vt100.net archive hosts all of these. DEC documents are the source for the DEC status on feature pages.

xterm¶

XTerm Control Sequences (ctlseqs) is the single most-cited document on the site. It is authoritative for xterm and, because every later emulator implemented some subset of it, it is the de facto index of what "a terminal" understands. It defines:

the OSC selector numbering (0–2 titles, 4/5/10–19 colors, 50 fonts, 52 clipboard, 104–119 resets) — OSC catalog;
XTWINOPS (CSI Ps t) — Window operations;
the DEC private modes above ?1000: mouse protocols, focus, bracketed paste, alternate screen — Modes, Mouse;
modifyOtherKeys and XTQMODKEYS — modifyOtherKeys;
XTGETTCAP, XTVERSION, XTPUSHSGR/XTPOPSGR, XTPUSHCOLORS — DCS, SGR.

Two companions matter:

terminfo(5) and the ncurses terminfo database, which name capabilities and are how applications discover them — Environment;
the xterm FAQ, which records the history behind several disputed behaviors.

xterm documents are the source for the xterm status.

Cross-emulator specifications¶

Document	Defines	TDN sections
terminal-wg specifications	The freedesktop working group's drafts; the venue where extensions become multi-vendor	referenced per feature
Hyperlinks in terminal emulators	OSC 8	Hyperlinks
Kitty keyboard protocol	`CSI … u` progressive enhancement	Kitty keyboard
Kitty graphics protocol	APC `G` image transfer and placement	Kitty graphics
Kitty text sizing	OSC 66	Text sizing
Kitty desktop notifications	OSC 99	Notifications
Synchronized output	DEC mode 2026	Modes
Color scheme reports	DEC mode 2031, `CSI ? 996 n`	Colors
FinalTerm / iTerm2 shell integration	OSC 133 and OSC 1337	Shell integration
Sixel graphics, libsixel	Sixel as implemented today	Sixel
win32-input-mode	`CSI … _` key records	win32-input-mode

These are the source for the Extension status when at least one other emulator has adopted them, and Vendor-private when not.

Surveys¶

Some documents define nothing and instead record what exists. TDN cites them for history and for the anatomy pages; they are never the source of a status.

Document	Records	TDN sections
terminal-wg N0001, Existing terminal sequence structures	The terminal-parsing subgroup's survey of every sequence shape in use or on record: the ESC code space, CSI marker and sub-parameter practice, control-string internals, non-standard introducers, and grammar-violating sequences from historical terminals	Escape, CSI anatomy, OSC anatomy, DCS, Control strings
A parser for DEC's ANSI-compatible video terminals	Paul Williams' state machine, reverse-engineered from VT500-series hardware; the de facto reference parser	CSI anatomy, Control strings

Emulator documentation¶

Each emulator's own escape-sequence document is linked from its terminal page. Where an emulator documents a behavior that no standard covers, the terminal page is the citation and the feature page marks it Vendor-private or Convention.

What is not written down¶

A great deal of terminal behavior has no document at all: what happens to pending wrap after DECSC, which terminator to prefer, how to query without blocking on a terminal that will never answer, how to survive tmux. TDN records that material in Practices, with the status Convention, and does not promote it to a standard however widely it is shared.