A shell that exits under a run answers exit N, and the log says exit before del

A dogfood agent ran `exit 3` through pty/run: the reader got ENOENT, and
the log went straight to del. The hosts now read a shell's exit status at
its pty's end as they do a command's; a run waiting on the line answers
`exit 3` with what it printed, the log says `exit <serial> 3` before
the pane's `del`, and an open run still stats after its pane is gone
(cat fstats its input). Pins cloud9 f35b7ed, whose stat of an open fid names
its open. Writes to a gone pane's pty/data, held open or not, fail ENOENT.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

1 files changed, 9 insertions, 0 deletions

diff --git a/src/Terminal.zig b/src/Terminal.zig
index 19e23624..a390b76b 100644
--- a/src/Terminal.zig
+++ b/src/Terminal.zig
@@ -961,6 +961,15 @@ pub const CommandOutput = struct {
 /// What the newest finished command printed: the screen text between its
 /// C and D marks, read from at most `max_rows` rows above its end, so a
 /// command that printed the whole history costs no more than its tail.
+/// The shell exited in the middle of a command (its `exit 3`): no end mark
+/// will come, so the command's output ends where the cursor is.
+pub fn endOutputHere(pane: *Pane) void {
+    if (comptime !enabled) return;
+    const state = pane.terminal orelse return;
+    const marks = &state.stream.handler;
+    if (marks.phase == .running and marks.out_end == null) marks.pinCursor(&marks.out_end, true);
+}
+
 pub fn commandOutput(pane: *Pane, gpa: std.mem.Allocator, max_rows: usize) !CommandOutput {
     // Unless there is text to read, whether the nothing it printed is the
     // whole of it.