A look takes acme's file:addr and :addr, and one that finds nothing changes nothing

A look at `file:/re/` or `:/re/` searched for the words instead of addressing, and a miss left an empty +Search pane and a cleared selection, while a hit answered the +Search pane on /look. Now an address after a colon (acme look.c:450) is evaluated in the file from its dot; a miss says no match and leaves the panes and the selection alone; a hit reads back as the pane the text is selected in. Both live in lookAt's one flow, so they are one change.

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

1 files changed, 11 insertions, 1 deletions

diff --git a/docs/fs.md b/docs/fs.md
index 95c1871e..e989aba8 100644
--- a/docs/fs.md
+++ b/docs/fs.md
@@ -299,7 +299,17 @@ write with EINVAL; a command that fails inside the editor is reported on the
 message row, not as a write error. Reading any of these files answers the
 serials of the panes the last command created, or, when it created none, the
 pane a look focused or the pane an exec acted on (even one it closed), one
-per line.
+per line; a look that found text answers the pane the text is selected in,
+not the hits buffer it opened.
+
+A look takes acme's addresses after a colon (editors/acme/look.c:450): a
+line written to `look` as `file:/re/`, `file:#n`, `file:$` or any address
+opens (or finds) the file and selects what the address names, evaluated
+from its dot; `:addr` does the same in the pane itself. `file:12` and
+`file:12:5` stay line and column. A bare `/re/` is a path, as in acme, and
+failing that a search for its text. A look that finds nothing, or an
+address that does not evaluate, says so on the message row and changes
+nothing: no buffer opens and the selection stays.
 
 `/pane/<n>/name` reads the pane's file name (a terminal's directory) and
 writing it renames the buffer; a relative name resolves against the pane's