"Jean-Michel.chabanne" <jeanmichel.chabanne@free.fr> writes:
> ... a first call to PQfinish(...) disconnects the client,
> [ PQstatus returns 'CONNECTION_BAD' ], and A SECOND call to PQfinish(..)
> make the client to crash with a system message 'segmentation fault'.
Freeing the same chunk of memory twice leads to a crash in most
implementations of malloc/free :-(. I don't think that libpq can be
expected to protect you from this. Don't PQfinish() the same connection
object more than once, because after the first one it's not a connection
object anymore --- only a dangling pointer to freed memory. For that
matter, you shouldn't call PQstatus() or any other libpq function using
an already-PQfinished connection pointer.
regards, tom lane
