In one embodiment, a peek operation may be used as a mechanism to see if {HEAD ~ any message} has arrived in {TAIL ~ the pipes} queue 
arrived in
In one embodiment , a peek operation may be used as a mechanism to see if { HEAD ~ any message } has arrived in { TAIL ~ the pipes } queue
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH