ush_queue&nbsp;=&nbsp;Unix.flush_queue&nbsp;=&nbsp;TCIFLUSH&nbsp;|&nbsp;TCOFLUSH&nbsp;|&nbsp;TCIOFLUSH
&nbsp;&nbsp;val&nbsp;tcflush&nbsp;:&nbsp;UnixLabels.file_descr&nbsp;-&gt;&nbsp;mode:UnixLabels.flush_queue&nbsp;-&gt;&nbsp;unit
&nbsp;&nbsp;type&nbsp;flow_action&nbsp;=&nbsp;Unix.flow_action&nbsp;=&nbsp;TCOOFF&nbsp;|&nbsp;TCOON&nbsp;|&nbsp;TCIOFF&nbsp;|&nbsp;TCION
&nbsp;&nbsp;val&nbsp;tcflow&nbsp;:&nbsp;UnixLabels.file_descr&nbsp;-&gt;&nbsp;mode:UnixLabels.flow_action&nbsp;-&gt;&nbsp;unit
&nbsp;&nbsp;val&n