pg_connect_poll

So the documentation on this function is pretty barebones (as is the case for a lot of thin PHP wrappers around C functions), but from what I've gathered by reading the libpq doc and trying various things, you should probably know the following :* Polling the connection while the underlying socket is busy will cause the connection (or at least the polling, I'm not sure) to fail.* As stated by the libpq documentation, "do not assume that the socket remains the same across PQconnectPoll calls"* The socket will become ready after every change in connection status, so the connection must be polled multiple times until the function returns "polling_ok" or "polling_failed".* "polling_active" can never be returned by libpq and has literally never been used anywhere ever, it has been an unused constant since day 1.What you need to do is use pg_socket get a PHP stream object corresponding to the current socket and wait after it before polling, like so:<?phpfunction pg_wait_connection_ready($conn) {    assert(is_resource($conn));    assert(get_resource_type($conn) === "pgsql link" || get_resource_type($conn) === "pgsql link persistent");    // "On the first iteration, i.e. if you have yet to call PQconnectPoll, behave as if it last returned PGRES_POLLING_WRITING."    $poll_outcome = PGSQL_POLLING_WRITING;    while (true) {        $socket = [pg_socket($conn)]; // "Caution: do not assume that the socket remains the same across PQconnectPoll calls."        $null = [];        if ($poll_outcome === PGSQL_POLLING_READING) {            stream_select($socket, $null, $null, 5);            $poll_outcome = pg_connect_poll($conn);        } else if ($poll_outcome === PGSQL_POLLING_WRITING) {            stream_select($null, $socket, $null, 5);            $poll_outcome = pg_connect_poll($conn);        } else {            break;        }    }}$db = pg_connect($conn_string, PGSQL_CONNECT_ASYNC);// Do things while the connection is getting readypg_wait_connection_ready($db);pg_query($sql);?>