Do not load .erlang from current dir

It may be confusing that "hidden" .erlang is loaded from the current
working directory. Use c:erlangrc([Dir1,..]) to search and
load .erlang from other places than "$HOME/.erlang".

Implies that c:erlangrc() needs to be documented.

3 files changed, 46 insertions, 21 deletions

diff --git a/lib/sasl/test/release_handler_SUITE.erl b/lib/sasl/test/release_handler_SUITE.erl
index 50932e89e4..63b48e7a4e 100644
--- a/lib/sasl/test/release_handler_SUITE.erl
+++ b/lib/sasl/test/release_handler_SUITE.erl
@@ -1835,24 +1835,32 @@ otp_10463_upgrade_script_regexp(cleanup,Config) ->
     code:del_path(filename:join([DataDir,regexp_appup,app1,ebin])),
     ok.
 
-no_dot_erlang(Conf) ->
-    PrivDir = ?config(data_dir,Conf),
-    {ok, OrigWd} = file:get_cwd(),
-    try
-	ok = file:set_cwd(PrivDir),
-
-	{ok, Wd} = file:get_cwd(),
-	io:format("Dir ~ts~n", [Wd]),
+no_dot_erlang(_Conf) ->
+    case init:get_argument(home) of
+        {ok,[[Home]]} when is_list(Home) ->
+            no_dot_erlang_1(Home);
+        _ -> ok
+    end.
 
+no_dot_erlang_1(Home) ->
+    DotErlang = filename:join(Home, ".erlang"),
+    BupErlang = filename:join(Home, ".erlang_testbup"),
+    try
+        {ok, Wd} = file:get_cwd(),
+        case filelib:is_file(DotErlang) of
+            true -> {ok, _} = file:copy(DotErlang, BupErlang);
+            false -> ok
+        end,
 	Erl0 =  filename:join([code:root_dir(),"bin","erl"]),
 	Erl = filename:nativename(Erl0),
 	Quote = "\"",
 	Args = " -noinput -run c pwd -run erlang halt",
-	ok = file:write_file(".erlang", <<"io:put_chars(\"DOT_ERLANG_READ\\n\").\n">>),
+	ok = file:write_file(DotErlang, <<"io:put_chars(\"DOT_ERLANG_READ\\n\").\n">>),
 
 	CMD1 = Quote ++ Erl ++ Quote ++ Args ,
 	case os:cmd(CMD1) of
-	    "DOT_ERLANG_READ" ++ _ -> ok;
+	    "DOT_ERLANG_READ" ++ _ ->
+                io:format("~p: Success~n", [?LINE]);
 	    Other1 ->
 		io:format("Failed: ~ts~n",[CMD1]),
 		io:format("Expected: ~s ++ _~n",["DOT_ERLANG_READ "]),
@@ -1862,7 +1870,7 @@ no_dot_erlang(Conf) ->
 	NO_DOT_ERL = " -boot no_dot_erlang",
 	CMD2 = Quote ++ Erl ++ Quote ++ NO_DOT_ERL ++ Args,
 	case lists:prefix(Wd, Other2 = os:cmd(CMD2)) of
-	    true -> ok;
+	    true -> io:format("~p: Success~n", [?LINE]);
 	    false ->
 		io:format("Failed: ~ts~n",[CMD2]),
 		io:format("Expected: ~s~n",["TESTOK"]),
@@ -1870,9 +1878,13 @@ no_dot_erlang(Conf) ->
 		exit({failed_to_start, no_dot_erlang})
 	end
     after
-	_ = file:delete(".erlang"),
-	ok = file:set_cwd(OrigWd),
-	ok
+        case filelib:is_file(BupErlang) of
+            true ->
+                {ok, _} = file:copy(BupErlang, DotErlang),
+                _ = file:delete(BupErlang);
+            false ->
+                _ = file:delete(DotErlang)
+        end
     end.
 
 %%%-----------------------------------------------------------------
diff --git a/lib/stdlib/doc/src/c.xml b/lib/stdlib/doc/src/c.xml
index 7666699183..697e1715e7 100644
--- a/lib/stdlib/doc/src/c.xml
+++ b/lib/stdlib/doc/src/c.xml
@@ -94,6 +94,15 @@
     </func>
 
     <func>
+      <name name="erlangrc" arity="1"/>
+      <fsummary>Load an erlang resource file.</fsummary>
+      <desc>
+        <p>Search <c>PathList</c> and load <c>.erlang</c> resource file if
+	found.</p>
+      </desc>
+    </func>
+
+    <func>
       <name name="flush" arity="0"/>
       <fsummary>Flush any messages sent to the shell.</fsummary>
       <desc>
diff --git a/lib/stdlib/src/c.erl b/lib/stdlib/src/c.erl
index c04a201ce1..9a447af5b7 100644
--- a/lib/stdlib/src/c.erl
+++ b/lib/stdlib/src/c.erl
@@ -668,19 +668,23 @@ lm() ->
     [l(M) || M <- mm()].
 
 %% erlangrc(Home)
-%%  Try to run a ".erlang" file, first in the current directory
-%%  else in home directory.
+%%  Try to run a ".erlang" file in home directory.
+
+-spec erlangrc() -> {ok, file:filename()} | {error, term()}.
 
 erlangrc() ->
     case init:get_argument(home) of
 	{ok,[[Home]]} ->
 	    erlangrc([Home]);
 	_ ->
-	    f_p_e(["."], ".erlang")
+            {error, enoent}
     end.
 
-erlangrc([Home]) ->
-    f_p_e([".",Home], ".erlang").
+-spec erlangrc(PathList) -> {ok, file:filename()} | {error, term()}
+                                when PathList :: [Dir :: file:name()].
+
+erlangrc([Home|_]=Paths) when is_list(Home) ->
+    f_p_e(Paths, ".erlang").
 
 error(Fmt, Args) ->
     error_logger:error_msg(Fmt, Args).
@@ -692,11 +696,11 @@ f_p_e(P, F) ->
 	{error, E={Line, _Mod, _Term}} ->
 	    error("file:path_eval(~tp,~tp): error on line ~p: ~ts~n",
 		  [P, F, Line, file:format_error(E)]),
-	    ok;
+	    {error, E};
 	{error, E} ->
 	    error("file:path_eval(~tp,~tp): ~ts~n",
 		  [P, F, file:format_error(E)]),
-	    ok;
+	    {error, E};
 	Other ->
 	    Other
     end.