MI: asynchronous operation details

[Vladimir Prus]

Hi,
so, in MI mode if I emit "-exec-continue" gdb starts inferiour and
immediately gives me back the prompt, accepting further commands.

However, I can't:
1. Understand what commands can meaningfully be issued while the inferior
is running. Say, all data read/write commands are likely to produce
inconsistent results if inferior is running.
2. Practically figure out which commands can be issued at all. Say, both
-data-evaluate-expression and -exec-continue just hang, returning
nothing. This is with CVS HEAD.

Do I understand correctly that asynchronous MI just don't exist in CVS HEAD,
and only command prompt loop is asynchronous? Even if so, and fully
asynchronous MI is coming, what's the answer to question (1) above?

- Volodya