pg_standby: How to check in which state the server is currently?

Hi list,

We had in past from time to time the issue, that the standby server is
stopping recovering, creating a new timeline and become up and running.
In parallel to check for the reasons of this behavior we are looking for
a clean way to check whether warm standby database is still in
recovering mode or has become ready. I did some search, but didn't found
any ready-2-use script for doing this on a stand alone basis (should
only be temp. solution that will be replaced by real monitoring later)
I looked for some solution checking ps for pg_standby and trying to
connect to database. But I'm not sure how 'secure' in terms of falls
positive and missed events this is.

Can anybody put me onto the right way here?

Cheers,
Frank