xrensis(at)gmail(dot)com writes:
> After the startup of the PostgreSQL server there is a state when it accepts
> incoming connections but generates "FATAL: the database system is starting
> up" as results for run queries.
This is not a bug, it's expected behavior.
> - Is there a known interface to check if the database is up and fully
> functional and ready for queries?
libpq's PQping() is a possibility.
regards, tom lane