src/cmd/acme: provide info on presense or absence of undo history (#528) It's sometimes useful to know whether there's been editing activity in a window. This PR adds that information to the ctl file. Change-Id: I21a342ac636dd5c7701b3ed560e3526867329c2c

tmac: rename IM (italic manual) to MR (manual reference) Suggested by G. Brandon Robinson.

tmac: introduce real manual reference macro instead of overloading IR The overloading of IR emits magic \X'...' sequences that turn into HTML manual links. But not all such IR invocations should be manual links; those had to be written to avoid the IR macro before. Worse, the \X'...' ending the IR causes troff to emit only a single space after a period. Defining a new IM macro for manual references fixes both problems. Fixes #441.

acme: add font control message

acme: add log file in acme root directory Reading /mnt/acme/log reports a log of window create, put, and delete events, as they happen. It blocks until the next event is available. Example log output: 8 new /Users/rsc/foo.go 8 put /Users/rsc/foo.go 8 del /Users/rsc/foo.go This lets acme-aware programs react to file writes, for example compiling code, running a test, or updating an import block. TBR=r R=r https://codereview.appspot.com/89560044

9term, acme: autoscroll Ignore scroll/noscroll window setting. Instead, scroll when the write begins in or immediately after the displayed window content. In the new scrolling discipline, executing "Noscroll" is replaced by typing Page Up or using the mouse to scroll higher in the buffer, and executing "Scroll" is replaced by typing End or using the mouse to scroll to the bottom of the buffer. R=r, r2 http://codereview.appspot.com/4433060

document tab width field

add errors file

Many small edits.

use macro for /usr/local/plan9

Some man pages.