This patch (against the current CVS sources) adds to libpq the functions

PQconnectStart
PQconnectPoll
PQresetStart
PQresetPoll
PQsetenvStart
PQsetenvPoll
PQsetenvAbort

and brings into the published interface

PQsetenv.

The first four are asynchronous analogues of PQconnectdb and PQreset -
they allow an application to connect to the DB without blocking on
remote I/O.

The PQsetenv functions perform an environment negotiation with the
server.

Internal to libpq, pqReadReady and pqWriteReady have been made available
across the library (they were previously static functions inside
fe-misc.c).  A lot of internal rearrangement has been necessary to
support these changes.

The API documentation has been updated also.

Caveats:

  o  The Windows code does not default to using non-blocking sockets,
since I have no documentation: Define WIN32_NON_BLOCKING_CONNECTIONS to
do that.

  o  The SSL code still blocks.


Ewan Mellor.