A pane's ctl reads acme's fields in acme's order, the undo and redo flags included, then pardes's own

Where plan9port's line has whether Undo and Redo have a step, pardes's had current, so a client reading acme's fields by position read a word for a flag. The two flags now follow the tab width, as in plan9port's winctlprint, and current|notcurrent and a REPL's id come after them.

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

1 files changed, 6 insertions, 4 deletions

diff --git a/docs/fs.md b/docs/fs.md
index dfd887ac..8464768b 100644
--- a/docs/fs.md
+++ b/docs/fs.md
@@ -608,10 +608,12 @@ it was read too, and for an empty range acts on its text, which is how such
 a line is done. A click in a file's body carries the offsets of the text it
 took; one in a terminal's body cannot, since that body is a history
 snapshot, and is also at `0 0` with its text. A click that takes no text
-sends nothing, as in acme. `ctl` reads acme's window status line — serial, tag length, body
-length, a reserved zero, the dirty flag, the width in cells, the font and the
-tab width — followed by rio's `current` or `notcurrent` (rio(4), `wctl`):
-whether the pane has the keyboard. It takes the pane's builtins (below),
+sends nothing, as in acme. `ctl` reads acme's window status line, field for
+field as plan9port's — serial, tag length, body length, isdir (0), the dirty
+flag, the width in cells, the font, the tab width, whether Undo has a step
+(1) and whether Redo has one — followed by pardes's own: rio's `current` or
+`notcurrent` (rio(4), `wctl`), whether the pane has the keyboard, and a
+REPL's id. It takes the pane's builtins (below),
 `get`, which reloads the buffer from the name it
 carries (unsaved edits are refused once, listed in `+Unsaved` with a short
 notice as Exit's are, the write failing `<name>: Modified (get again to