https://gist.github.com/bb01a85404e6b445dcb3#file_resolve_do...

    % -*- erlang -*-                                                                                                                              
    %%! -smp enable                                                                                                                               
                                                                                                                                                  
    worker(Hostname) ->                                                                                                                           
        {ok, IP} = inet:getaddr(Hostname, inet),                                                                                                  
        io:format(                                                                                                                                
          "~s => ~s~n",                                                                                                                                 
          [ip_to_string(IP)]                                                                                                                      
         ).                                                                                                                                       
                                                                                                                                                  
    ip_to_string({N1,N2,N3,N4}) ->                                                                                                                
        io_lib:format(                                                                                                                            
          "~w.~w.~w.~w",                                                                                                                          
          [N1,N2,N3,N4]                                                                                                                           
         ).                                                                                                                                       
                                                                                                                                                  
    main([DomainFile]) ->                                                                                                                         
        {ok, Bin} = file:read_file(DomainFile),                                                                                                   
        String = binary_to_list(Bin),                                                                                                             
        Domains = string:tokens(String, "\n"),                                                                                                    
        plists:foreach(                                                                                                                           
          fun(Domain) -> worker(Domain) end,                                                                                                      
          Domains                                                                                                                                 
        ).