When
async> is true (not zero), PQgetCopyData>
will not block waiting for input; it will return zero if the COPY is still
in progress but no complete row is available. (In this case wait for
-read-ready before trying again; it does not matter whether you call
-
PQconsumeInput>.) When async> is
+read-ready and then call PQconsumeInput> before calling
+
PQgetCopyData> again.) When async> is
false (zero), PQgetCopyData> will block until data is available
or the operation completes.