Constraining mouse cursor globally in xorg

[Alex White]

Hi,

Not sure if this is the right place for this question, but here goes..

I need to constrain the mouse cursor in xorg, to prevent it reaching an  
area of screen that is not visible to the user (don't ask).

I've noticed that there is support for this within the x server using the  
ConstrainCursor function. What this function provides is exactly what I  
need.

What's not clear to me is how I can access this function from the  
application level. (or is it internal only?). None of the pScreen member  
functions appear to be exposed in the libraries I've searched.

Do I need to write a simple xorg module to do this?

Any suggestions on how to proceed?

Thanks,
Alex.