Find and Grep share one +Search a directory, each run replacing the last

Each Grep with a new pattern opened another +Search, until the column
refused panes. Find and Grep now reuse their directory's one, as acme
reuses +Errors, and the exec reads back the pane it filled; a plain
word's LookWord list search keeps a pane a pattern as before.

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

1 files changed, 4 insertions, 1 deletions

diff --git a/docs/fs.md b/docs/fs.md
index 9b5b9d64..a0b3dcf7 100644
--- a/docs/fs.md
+++ b/docs/fs.md
@@ -736,7 +736,10 @@ whose directory is gone says `look: <dir>: no such directory` -- and for a
 Find or Grep that finds nothing, `grep: no match, not found`; Grep walks
 every pane's directory on this host, passing over panes of the served
 tree (`/virtual/`, a peer's `/n/<name>/`) and directories not there,
-so none of them spoils the rest, ENOSPC for no room or
+so none of them spoils the rest; Find and Grep share one `+Search` a
+directory, each run replacing what the last showed, as acme reuses a
+directory's `+Errors` (the exec reads that pane back), while a plain
+word's `LookWord list` search keeps a pane a pattern, ENOSPC for no room or
 slot, EBUSY for a held lock) -- and logs its reason exactly once, as `err <serial|->
 <file>: <why>`, with no `msg` for it. A builtin a click runs (Save, get's
 `Modified`, Tty with no room, Edit) is no exception. What is not a