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, 4 insertions, 3 deletions

diff --git a/src/tty/tty.zig b/src/tty/tty.zig
index d17316e8..b18f4de5 100644
--- a/src/tty/tty.zig
+++ b/src/tty/tty.zig
@@ -1050,12 +1050,13 @@ const Shell = struct {
                         return true;
                     }
                     _ = libc.close(pt.file.handle);
-                    // Unwatched, a command's exit is read here, as its end.
+                    // Unwatched, a command's exit is read here, as its end,
+                    // and a shell's, for a run waiting on it and the log.
                     const command = if (core.panes[e.id]) |pn| pn.command != null else false;
-                    const status = if (command) host_io.exitStatus(pt.pid, 100) else null;
+                    const status = host_io.exitStatus(pt.pid, 100);
                     if (status == null) host_io.retireShell(pt.pid);
                     s.ptys[e.id] = null;
-                    if (command) core.update(.{ .exited = .{ .pane = @intCast(e.id), .status = status } });
+                    if (command or status != null) core.update(.{ .exited = .{ .pane = @intCast(e.id), .status = status } });
                 }
                 core.update(.{ .eof = .{ .pane = @intCast(e.id) } });
             },