[R-SIG-Mac] R.app not handling events

[Duncan Murdoch]

Every now and then R.app stops responding to various events while a 
long-running command is executing.  I can't scroll the console to look 
at earlier results, and I don't see partial results until the whole 
computation is complete.  If I ask MacOS to switch to that window, it 
won't come to the top (though clicking on it does bring it up, but I 
need to be able to see part of it to do that).

Once it finishes it returns to the console prompt and things look fine, 
but the same thing happens during the next long-running command.

This happens every now and then, but I haven't spotted the cause.  The 
only solution I've found is to quit the session and restart it.

Does anyone know what might be causing this, or a way to fix it without 
ending the session?

Duncan Murdoch