Determine the X Display edge in a multi X screen configuration

[Adam Jackson]

On Sat, 2017-10-21 at 13:08 -0700, Jim Westfall wrote:

> I'm wanting to determine when the mouse pointer is near the edge of the X 
> Display.  
> 
> In the case when there is only one X screen, the edge of the X screen 
> will be the edge of the X Display.  However when multiple separate X 
> screens (zaphod) make up the X Display using this method is not 
> possible.  For each X screen, there will be at least one edge that is 
> adjacent to another X screen.  As such those edges are not the edge of the 
> X display.
> 
> Originally I figured I would just be able to query the X server for 
> details about the arrangement of the X screens and from that figure out 
> the adjacent X screen edges.  However I've been unable to find any function 
> that provides this information.  Does such a function exist? and/or is 
> there some better way to determine if a given X screen edge is the edge of 
> the X display?

Such a function does not exist. As far as the protocol is concerned,
screens do not have any relative geometry.

- ajax