-module(hello).
-export([create_cookie/0]).

-include_lib("kernel/include/file.hrl").

create_cookie() ->
    Name = ".erlang.cookie",
    Cookie = "macaroon\n",
    case file:open(Name, [write, raw]) of
	{ok, File} ->
	    R1 = file:write(File, Cookie),
	    ok = file:close(File),
	    R2 = file:raw_write_file_info(Name, make_info()),
	    case {R1, R2} of
		{ok, ok} ->
		    ok;
		{{error,Reason}, _} ->
		    {error,
		     lists:flatten(
		       io_lib:format("Failed to write to cookie file '~ts': ~p", [Name, Reason]))};
		{ok, {error, Reason}} ->
		    {error, "Failed to change mode: " ++ atom_to_list(Reason)}
	    end;
	{error,Reason} ->
	    {error,
	     lists:flatten(
	       io_lib:format("Failed to create cookie file '~ts': ~p", [Name, Reason]))}
    end.

make_info() ->
    #file_info{mode=8#400}.