libpq: How to cancel a COPY ... TO statement?

[Daniel Frey <d.frey@xxxxxx>]

Hi,

after sending a COPY ... TO statement with PQsendQuery(), how can I cancel it properly?

I tried using PQcancel(), but it seems to have no effect. Calling PQgetCopyData() or PQgetResult() afterwards does not go into a failure state. And I don't want to call PQgetCopyData() until it returns -1, as this might be a lot of data being read from the server that I don't need.

BR, Daniel