TP3/TERMINAL.md

TERMINAL — text configuration instead of a patched binary

TINST installs terminal escape sequences by writing them into TURBO.COM. This port does the same job with a text file, TP3.TRM, that tpshell reads at startup. The shell never modifies itself; the file can be edited, copied, versioned or generated, and a bad file is a data error rather than a corrupted executable.

The file

Plain text, one KEY=value per line. ; at the start of a line is a comment. Blanks around the key and value are ignored; the key is case-insensitive. Unknown keys are ignored (so files can carry fields another tool needs).

; TP3.TRM
NAME=ANSI
CLEAR=\e[2J\e[H
HOME=\e[H
GOTO=\e[%r;%cH
NORMAL=\e[0m
MARKED=\e[1;7m
BEEP=^G

key	meaning
NAME	a label, not interpreted
CLEAR	clear the screen (and usually home the cursor)
HOME	home the cursor
GOTO	cursor addressing, with the placeholders below
NORMAL	normal text attribute
MARKED	highlighted attribute (the shell's command letters)
BEEP	the bell

Values

Values are decoded, so the file stays readable:

written	byte
\e or \E	ESC (27)
\r	CR (13)
\n	LF (10)
\t	TAB (9)
\\	a backslash
^X	control-X (X uppercased, minus 64): ^G = BEL (7)
anything else	itself

GOTO placeholders:

placeholder	output
%r	the row in decimal (1-based)
%c	the column in decimal (1-based)
%R	one byte, row + 31 (VT52-style)
%C	one byte, col + 31
%%	a literal %

A missing TP3.TRM means the built-in ANSI defaults (the sequences the shell had before there was a config). A malformed line leaves the defaults (and anything read before it) in place; it never silently half-configure the screen.

tp3cfg

The configurator - TINST's role, without the patch. It lists the terminals it knows, asks for one, and writes TP3.TRM.

cd shell
./tp3cfg            # list, choose, write TP3.TRM

A terminal is added by one Build case in Tp3Cfg.mod and one bump of NumTerms; the sequences are written in the same readable spelling as the file. tp3cfg is built by make alongside tpshell.

Current table: ANSI, VT100 (ANSI-compatible for what the shell emits), VT52 (raw-byte cursor addressing, %R/%C).

Extracting TINST's full terminal table (next measurement)

TINST.COM embeds its table; TINST.MSG is only its UI text, and the disassembly in Resources/turbopascal3source is TURBO, not TINST. The method that measures rather than guesses:

1. Run the original TINST in dosemu once per terminal, selecting each entry from its menu.
2. Save the patched TURBO.COM each time and diff it against the untouched copy. TINST patches known offsets, so every terminal's exact escape strings fall out at the offsets TINST itself uses.
3. Convert each diff into a tp3cfg Build case.

That is deliberately not done by transcription: the sequences are what the original writes, and the diff is the evidence. Until it is done, the table above is the curated subset the shell needs.

Not in this step: key remapping

TINST also remaps the editing keys (the cursor/insert/delete/block command table visible in TINST.MSG). The shell's editor hard-codes its keys today. The same design extends to it - a KEYS section in the config read by Editor.mod - and is a separate step.