'Determine whether the user-space send buffer for this transport is full
or not.
When the buffer contains more than C{self.bufferSize} bytes, it is
considered full.  This might be improved by considering the size of the
kernel send buffer and how much of it is free.
@return: C{True} if it is full, C{False} otherwise.'

def _isSendBufferFull(self):

    return ((len(self.dataBuffer) + self._tempDataLen) > self.bufferSize)
