gdkCursorNewFromPixbuf(display, source, x, y)displayGdkDisplay]  the GdkDisplay for which the cursor will be createdxygdkDisplaySupportsCursorAlpha and 
gdkDisplaySupportsCursorColor can be used to determine
whether RGBA cursors are supported; 
gdkDisplayGetDefaultCursorSize and 
gdkDisplayGetMaximalCursorSize give information about 
cursor sizes.
  
On the X backend, support for RGBA cursors requires a
sufficently new version of the X Render extension.  Since 2.4