module Process

(0..mask).to_a.map{ |n| mask[n] }
mask = Process.get_affinity.first

this approach:
indicating the flag value of each processor, you can use something like
If you want to convert a decimal bit vector into an array of 0's and 1's

Process.get_affinity # => [[9], [15]]
# System has 4 processors, current process only allowed on 1 and 4.

Process.get_affinity # => [[15], [15]], where '15' is 1 + 2 + 4 + 8
# System has 4 processors, current process is allowed to run on all.

Example:

system.
which each bit represents the processors that are configured into a
process is allowed to run on. A system affinity mask is a bit vector in
A process affinity mask is a bit vector indicating the processors that a

containing the system affinity mask. Both are decimal values.
array, with the first containing the process affinity mask, and the second
current process if no pid is provided. The return value is a two element
Returns the process and system affinity mask for the given +pid+, or the

def get_affinity(int = Process.pid)
  pmask = FFI::MemoryPointer.new(:ulong)
  smask = FFI::MemoryPointer.new(:ulong)
  if int == Process.pid
    unless GetProcessAffinityMask(GetCurrentProcess(), pmask, smask)
      raise SystemCallError, FFI.errno, "GetProcessAffinityMask"
    end
  else
    begin
      handle = OpenProcess(PROCESS_QUERY_INFORMATION, 0 , int)
      if handle == 0
        raise SystemCallError, FFI.errno, "OpenProcess"
      end
      unless GetProcessAffinityMask(handle, pmask, smask)
        raise SystemCallError, FFI.errno, "GetProcessAffinityMask"
      end
    ensure
      CloseHandle(handle)
    end
  end
  [pmask.read_ulong, smask.read_ulong]
end