The root look and exec read back what a ctl write touched too

After a pane made by Tty or Newcol written to a ctl, /look and /exec still
read the serials of the last look or exec, and a script took the old pane for
the new one. A ctl write now resets them and records what each line made, or
else the pane it ran at, as a look or exec does.

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

1 files changed, 2 insertions, 1 deletions

diff --git a/docs/fs.md b/docs/fs.md
index 03f250af..96d0eb3a 100644
--- a/docs/fs.md
+++ b/docs/fs.md
@@ -82,7 +82,8 @@ Existing Plan9port/v9fs clients need a userspace bridge for QUIC.
 /README      this guide, also src/fs-help.txt
 /index       one line per pane: serial, kind (text|term|pdf|image), dirty flag, name
 /status      pid, version and pane count
-/look        write a line: a right click on it at the active pane; read: the serials it touched
+/look        write a line: a right click on it at the active pane; read: the serials the last
+             look, exec or ctl write touched (made, else acted at)
 /exec        write a line: a middle click; read the same serials
 /log         recent events, one a line: new|del|rename|save <serial> <name>, msg <serial|-> <text>,
              dump|restore <path>, err <serial|-> <file>: <why>;