module Ethon::Curls::Codes

def multi_codes

https://github.com/bagder/curl/blob/master/include/curl/multi.h for details
Curl-Multi socket error codes, refer 
def multi_codes
  [
    :call_multi_perform, -1,
    :ok,
    :bad_handle,
    :bad_easy_handle,
    :out_of_memory,
    :internal_error,
    :bad_socket,
    :unknown_option,
    :last
  ]
end