Bug report

Bug description:

On Windows, IocpProactor.recvfrom_into() defines its third parameter as flags:

def recvfrom_into(self, conn, buf, flags=0):
    ...
    ov.WSARecvFromInto(conn.fileno(), buf, flags)

However, _overlapped.Overlapped.WSARecvFromInto() expects:

(handle, buf, size, flags=0)

so the value named flags is actually passed as size and used as the receive length (nbytes). The parameter is therefore misnamed and inconsistent with the surrounding APIs.

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

Linked PRs

• gh-157418: Correct the IocpProactor recvfrom_into parameter name #157422