link 'help' to general docs

svn: r12374

collects/scribblings/reference/help.scrbl

@@ -1,9 +1,18 @@
 #lang scribble/doc
 @(require "mz.ss"
+          scribble/struct
           (for-label scheme/help
                      net/url
                      scheme/gui))
 
+@; Beware of this hard-wired link to the main doc page:
+@(define main-doc-page
+   (link "../index.html"
+         #:style (make-with-attributes 
+                  "plainlink" 
+                  `((onclick . ,(format "return GotoPLTRoot(\"~a\");" (version)))))
+         "main documentation page"))
+
 @title{Interactive Help}
 
 @note-init-lib[scheme/help]
@@ -15,12 +24,15 @@
 @defform/none[#:literals (help) (help #:search datum ...)]
 )]{
 
-Searches the documentation, and opens a web browser (using the user's
-selected browser) to display the results. See
-@schememodname[net/sendurl] for information on how the user's browser
-is launched.
+@emph{For general help, see the @|main-doc-page|.}
 
-A simple @scheme[help] or @scheme[(help)] form opens this page.
+The @scheme[help] form searches the documentation and opens a web
+browser (using the user's selected browser) to display the results.
+
+@margin-note{See @schememodname[net/sendurl] for information on how
+the user's browser is launched to display help information.}
+
+A simple @scheme[help] or @scheme[(help)] form opens this page. 
 
 A @scheme[(help id)] form looks for documentation specific to the
 current binding of @scheme[id]. For example,