[DOM2 Events] UIEvent::Button

The definition of the UIEvent interface [1] defines a button attribute
to show which button changed for the event.  What are the possible
values of this attribute?  That is, does 0=left, 1=middle, 2=right,
3=multiple, or what?

Also, while I'm asking, should the units for {client,screen}{X,Y} be
given in the spec, or not?  (I would think it would be pixels when
relevant, or characters for tty media types.)  Is the upper left 0,0?

David

[1] http://www.w3.org/TR/WD-DOM-Level-2/events.html#Level2-Events-UIEvent

L. David Baron     Rising Sophomore, Harvard     dbaron@fas.harvard.edu
Links, SatPix, CSS, etc.        < http://www.fas.harvard.edu/~dbaron/ >
Summer Intern, Netscape - however, opinions are entirely my own, etc.