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, 5 insertions, 7 deletions

diff --git a/src/detached/server.zig b/src/detached/server.zig
index 3921d8d9..2fc165eb 100644
--- a/src/detached/server.zig
+++ b/src/detached/server.zig
@@ -706,16 +706,14 @@ pub const Session = struct {
         // it would hang up one that runs on without it.
         // Its exit, if it came first, is told now its output is in.
         if (pt.cmd.watched) return host_io.commandEof(s.core, &s.ptys, pane, s, closeWatched);
-        // 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 unwatched = if (s.core.panes[pane]) |pn| pn.command != null else false;
-        var status: ?u8 = null;
-        if (unwatched) {
-            status = host_io.exitStatus(pt.pid, 100);
-            if (status != null) pt.pid = 0; // reaped: no shell to retire
-        }
+        const status = host_io.exitStatus(pt.pid, 100);
+        if (status != null) pt.pid = 0; // reaped: no shell to retire
         s.closePty(pane);
         s.harvest();
-        if (unwatched) s.core.update(.{ .exited = .{ .pane = pane, .status = status } });
+        if (unwatched or status != null) s.core.update(.{ .exited = .{ .pane = pane, .status = status } });
         s.core.update(.{ .eof = .{ .pane = pane } });
     }