pardes.git/src/ninep/pty.zig, branch release-0.24

A shell's prompt drawn on the alternate screen is a prompt: a terminal whose program was killed there is no longer busy for ever

2026-10-01T07:57:43Z

htop killed with `sig KILL` leaves the emulator on its alternate screen; bash comes back and draws its prompt there, marks and all, but promptInputReady refused any prompt on the alternate screen, so pty/status said busy 1 and pty/run answered a bare `busy` for good. A prompt mark there now counts. A run sent at such a prompt leaves the alternate screen in the emulator first, as a reused command pane does, so its output lands on the primary screen and is read whole, not `exit 0 cut` with nothing. Busy there with no prompt drawn, and no program name to give, a run is told `busy alternate screen`. Co-Authored-By: Claude Opus 5.5

pty/run after a clear answers what the command printed from the clear on, whole; cut only when its start really scrolled away

2026-10-01T05:47:36Z

A clear (ED 2, ED 3, a reset) under a running command marked its output lost, so `clear; ls` answered only "exit 0 cut". The output's start is now pinned again at the screen's top after the erase: what the command prints from there is its answer, whole, and a cut is said only when that start leaves the scrollback. Co-Authored-By: Claude Opus 5.5

winsize refuses fewer than 2 rows, saying so, and its range reads 1x2 to 4096x4096 as the docs say

2026-10-01T03:12:17Z

`winsize 20 1` was taken and quietly raised to 2 rows, so the write succeeded with a size other than the one asked for. The range refusal also said "1x1 to 4096x4096", although fs.md says at least 2 rows. One row is now refused with "invalid winsize: at least 2 rows", and the range text starts at 1x2. size already refused anything under 20x6 with a text that names it. Co-Authored-By: Claude Opus 5.5

A run whose output a redraw moved above its start answers cut, never an empty whole

2026-10-01T03:12:17Z

pty/run reads a command's output between its C and D marks. When the end landed at or before the start, it answered `exit 0` with no output, as if nothing was printed. That happens when the shell redraws its prompt over the output, as it can in a window two rows high (winsize 10 2). Now only equal marks mean nothing was printed. An end at the top-left cell or above the start says `cut`, since how much was printed is not known. bash, fish, long lines and 3000-line outputs at winsize 10 2 all came back whole on this build, so the dogfood's loss could not be reproduced directly. The test drives the marks into the inverted case the loss needs. Co-Authored-By: Claude Opus 5.5

Terminal.zig is terminal.zig: a file of functions and no fields takes a namespace's lowercase name

2026-10-01T03:12:17Z

The last of the deferred renames, now that the tty and theme agents have landed: panes.terminal at its importers, the alias lines in Text.zig and File.zig and panes.zig's own uses following. dump.zig's Terminal struct, a dump record, is not this. The served sources list and docs/design.typ name the new file. test/perf.zig's references change, so the three perf baselines take its new harness id with their numbers as recorded. No behaviour changes. Co-Authored-By: Claude Opus 5.5

pty/run takes one line a run, its answer read before the next

2026-10-01T03:12:16Z

Two lines -- in one write, or as bash writes them, a line at a time on one open -- each ran, and the first's answer was lost under the second's. A write with more than one line, or a next line before the last answer is read, is now refused, EINVAL. Co-Authored-By: Claude Opus 5.5

pty/ctl exec on a command pane is refused: a command pane does not restart

2026-10-01T03:12:16Z

exec on a finished command pane ran its line again, silently, with no header, footer or records. It is now refused, EINVAL, invalid exec: a command pane does not restart. Co-Authored-By: Claude Opus 5.5

Every catch unreachable, orelse unreachable and syscall assert outside tests is a real refusal or says why it cannot fire

2026-10-01T03:12:16Z

A sweep for round 23's crash: a run's answer (pty/run) was bufPrint'd into 48 bytes with catch unreachable, so a foreground program's long name (macOS gives up to 32 bytes) panicked; it now cuts at the room, keeping its newline, in 96 bytes. The rest were numbers into buffers sized for them, a braille codepoint, pthread calls on the queue's own mutex, and pdf_view's resolved outline entries: each now carries a one-line comment saying why it cannot fire. Co-Authored-By: Claude Opus 5.5

A pty/ctl exec that cannot start its shell keeps the one running

2026-10-01T03:12:16Z

Each host closed the running shell before it forked the new one, so an exec whose shell failed left the pane with none and later runs answered error shell gone. A shell not there is now refused up front, and every host starts the new shell first, replacing the old only once the close-on-exec pipe says it ran; a failure there is only said (restartFailed). Co-Authored-By: Claude Opus 5.5

pty/ctl exec fails the write when the shell cannot start; a directory removed under a shell leaves its name

2026-10-01T03:12:16Z

`exec` on pty/ctl restarted a shell in a directory that was gone, the write succeeding and the pane dead; and the pane was then renamed ` (deleted)` from /proc, so a restart failed even once the directory was back. `exec` is now refused up front, ENOENT, where the directory is gone; a shell the host cannot start fails the waiting write (late failure, as a Save's); and a `(deleted)` cwd is no name to take. Co-Authored-By: Claude Opus 5.5