module Process

32768 => Process::ABOVE_NORMAL_PRIORITY_CLASS
16384 => Process::BELOW_NORMAL_PRIORITY_CLASS
256 => Process::REALTIME_PRIORITY_CLASS
128 => Process::HIGH_PRIORITY_CLASS
64 => Process::IDLE_PRIORITY_CLASS
32 => Process::NORMAL_PRIORITY_CLASS

Possible return values are:

information, so it is effectively always Process::PRIO_PROCESS.
You can only retrieve process information, not process group or user
The +kind+ parameter is ignored but required for API compatibility.

correspond to higher priority classes.
the default implementation, lower return values do not necessarily
Retrieves the priority class for the specified process id +int+. Unlike

def getpriority(kind, int)
  raise TypeError, kind unless kind.is_a?(Integer) # Match spec
  raise TypeError, int unless int.is_a?(Integer)   # Match spec
  int = Process.pid if int == 0 # Match spec
  handle = OpenProcess(PROCESS_QUERY_INFORMATION, 0, int)
  if handle == 0
    raise SystemCallError, FFI.errno, "OpenProcess"
  end
  begin
    priority = GetPriorityClass(handle)
    if priority == 0
      raise SystemCallError, FFI.errno, "GetPriorityClass"
    end
  ensure
    CloseHandle(handle)
  end
  priority
end