Is this pid (using epoll, on amd64, on EM 1.0.0) currently blocked in the EM mainloop?

is_in_epoll.rb

def is_in_eventmachine(pid)
  begin
    syscall = File.read("/proc/#{pid}/syscall")
  rescue Errno::ENOENT
    return false
  end

  words = syscall.split(" ")
  if words.length != 9
    # Running, or in an fault handler
    return false
  end

  scno = words[0].to_i
  if scno != 23
    # 23 is select on amd64
    return false
  end

  if !words[3].to_i(16).zero? || !words[4].to_i(16).zero?
    # Non-empty writer or exception lists -- not eventmachine
    return false
  end

  if words[5].to_i(16).zero?
    # NULL timeout -- not eventmachine
    return false
  end

  maxfd = words[1].to_i(16)
  emfd = maxfd - 1
  begin
    fd = File.readlink("/proc/#{pid}/fd/#{emfd}")
  rescue Errno::ENOENT
    return false
  end

  return fd == "anon_inode:[eventpoll]"
end