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