ActivePoll -> Timer, Dpc, Handles


   FCB -> Polls Involved In ...


What poll needs to do:
 Accumulate:
  for each fcb
   If error is set, check error condition on fcb on entry
   If writable is set, check fcb on entry for zero send content
   If readable is set, check fcb has nonzero read content

 If any handle was not valid, complete fail

 If any of the above checks were true, complete success
 Otherwise:
  make an active poll object
  for each fcb, make a poll entry
   chain the poll entry to the fcb
   set summary bits in fcb state for polling (what must be polled)
  chain the active poll object to the device ext
  set timer and dpc
  pending

complete select:
 for each fcb
  find the poll entry in the fcb and unchain it
  rescan poll bits for this fcb
 get irp from poll object, and deallocate poll object
 complete irp

select timeout:
 Find the poll object in the device ext chain and unchain it
 complete select with timeout

fcb send complete and connect complete:
 if no more send irps and send bit set in summary
  find each poll entry with send bit set and complete select with (1) on it

fcb recv complete:
 if fcb has recv data and recv bit set in summary
  find each poll entry with recv bit set and complete select with (1) on it