[GRASS5] Autopan weirdness in v.digit

[Eric G. Miller]

There's some erratic behavior in v.digit under the PAN menu when
autopanning is enabled (apparently the default unless
GRASS_PAN_THRESHOLD=0).  Anyway, it just starts eating up all of the user
requests as it gets stuck in a tight loop.  Only way out is to kill -9 it.
 It seems to occur when R_get_location_with_pointer() is called with a
"-1" for the button argument, whereby the server code returns pretty much
immediately with some garbage if the monitor doesn't have focus, whereby
v.digit enters into some bogus calculations with the returned screen
coordinates (which might be any old thing), whereby v.digit probably calls
a redraw and then returns to the top of the loop, whereby the Xserver says
"hey I'm busy" and returns any old garbage, and on and on.

Actually,  I'm not sure I have the events exactly pinned.  But
nonetheless, it is extremely undesirable behavior.  I gave a short go at
trying to catch and handle the behavior, but I wasn't quite catching it. 
I'll try and look at it some more tomorrow...

-- 
Eric G. Miller <egm2 at jps.net>