anchor.diff:  -export([path_split/1]).
   -export([urlsplit/1, urlsplit_path/1, urlunsplit/1, urlunsplit_path/1]).
   -export([guess_mime/1, parse_header/1]).
  --export([shell_quote/1, cmd/1, cmd_string/1, cmd_port/2]).
  +-export([shell_quote/1, cmd/1, cmd_string/1, cmd_port/2, cmd_status/1]).
   -export([record_to_proplist/2, record_to_proplist/3]).
   -export([safe_relative_path/1, partition/2]).
   -export([parse_qvalues/1, pick_accepted_encodings/3]).
  
positive.code: %% @doc Create a shell quoted command string from a list of arguments.
  cmd_string(Argv) ->
      string:join([shell_quote(X) || X <- Argv], " ").
  
  %% @spec join([string()], Separator) -> string()
  %% @doc Deprecated, use string:join/2.
  
negative.code:     ok.
  
  shell_quote_test() ->
      ?assertEqual(
         "\"foo \\$bar\\\"\\`' baz\"",
         shell_quote("foo $bar\"`' baz")),
      ok.
  
  cmd_port_test_spool(Port, Acc) ->
  