frame callback perfectioned

README.md

@@ -1,3 +1,41 @@
 # rackedit
 
-Starts a simple racket editor window from DrRacket or the racket command line, given a file to edit. 
+`rackedit` opens a simple Racket editor window for a file. It can be used from
+DrRacket, from a Racket program, or from the Racket command line.
+
+The package exports one procedure:
+
+```racket
+(require rackedit)
+
+(rkdt "notes.rkt")
+```
+ 
+By default `rkdt` shows the editor and returns immediately. Use `#:wait? #t`
+when execution should continue only after the editor is closed:
+
+```racket
+(rkdt "notes.rkt" #:wait? #t)
+```
+
+The initial window geometry can be specified with `#:width`, `#:height`, `#:x`,
+and `#:y`. Window positions and sizes are remembered per internal editor number
+and per screen configuration.
+
+The frame can be customized with `#:frame-cb`. For example:
+
+```racket
+(require racket/class
+         rackedit)
+
+(rkdt "notes.rkt"
+      #:frame-cb
+      (λ (frame)
+        (send frame set-label "Notes")))
+```
+
+The standard File menu does not contain the Exit/Quit command, so closing one
+editor window does not imply exiting the application that opened it.
+
+Full API documentation is included as Scribble documentation in
+`scrbl/rkdt.scrbl`.