.IR whatnowproc ,
including
one of the standard shells. As a result, it's not possible to pass
-information via an argument list.
+information via an argument list. The convention is that environment
+variables whose names are all upper-case are user-settable; those
+whose names are lower-case only are used internally by nmh and should
+not generally be set by the user.
.PP
If the
.B WHATNOW
.PP
.B $mheditor
.RS 5
-This is set to tell the
+This is set by
+.BR comp ,
+.BR repl ,
+.BR forw ,
+and
+.B dist
+to tell the
.I whatnowproc
the user's choice of
editor (unless overridden by