Function _net_read

dns/query.py:1079–1097

Read the specified number of bytes from sock. Keep trying until we either get the desired amount, or we hit EOF. A Timeout exception will be raised if the operation is not completed by the expiration time.

(sock, count, expiration)

def _net_read(sock, count, expiration):
    """Read the specified number of bytes from sock.  Keep trying until we
    either get the desired amount, or we hit EOF.
    A Timeout exception will be raised if the operation is not completed
    by the expiration time.
    """
    s = b""
    while count > 0:
        try:
            n = sock.recv(count)
            if n == b"":
                raise EOFError("EOF")
            count -= len(n)
            s += n
        except (BlockingIOError, ssl.SSLWantReadError):
            _wait_for_readable(sock, expiration)
        except ssl.SSLWantWriteError:  # pragma: no cover
            _wait_for_writable(sock, expiration)
    return s


def _net_write(sock, data, expiration):