Dump an XML document to an I/O buffer. Warning ! This call
          xmlOutputBufferClose() on buf which is not available after
           this call.

def saveFileTo(self, buf, encoding):
        """Dump an XML document to an I/O buffer. Warning ! This call
          xmlOutputBufferClose() on buf which is not available after
           this call. """
        if buf is None: buf__o = None
        else: buf__o = buf._o
        ret = libxml2mod.xmlSaveFileTo(buf__o, self._o, encoding)
        return ret