text extents

[Steven J Abner]

Good day to all,
 Question: Created an xcb surface for 'drawable' and currently create a 
similar for a cairo_t* to gather extents. I did this because of 
uncertainty of cairo internal workings. Is it safe, no actual drawing 
to surface, to just use the xcb surface to create a cairo_t* for 
gathering of extents? Or, put in other words, do I need the similar 
surface? Can this be done knowing the surface may be in it's rending 
state while
query of extents?
  Steve