Merge branch 'siri/kernel/heart-set_cmd-unicode/OTP-10843'

* siri/kernel/heart-set_cmd-unicode/OTP-10843:
  Convert command string to encoded binary in heart:set_cmd/1

Conflicts:
	lib/kernel/src/heart.erl

2 files changed, 19 insertions, 10 deletions

diff --git a/lib/kernel/doc/src/heart.xml b/lib/kernel/doc/src/heart.xml
index f5028a5559..3ec33d2f18 100644
--- a/lib/kernel/doc/src/heart.xml
+++ b/lib/kernel/doc/src/heart.xml
@@ -118,8 +118,13 @@
           the system. The new Erlang runtime system will (if it
           misbehaves) use the environment variable
           <c>HEART_COMMAND</c> to reboot.</p>
-        <p>Limitations: The length of the <c><anno>Cmd</anno></c> command string
-          must be less than 2047 characters.</p>
+
+        <p>Limitations: The <c><anno>Cmd</anno></c> command string
+        will be sent to the heart program as a ISO-latin-1 or UTF-8
+        encoded binary depending on the file name encoding mode of the
+        emulator (see
+	<seealso marker="kernel:file#native_name_encoding/0"><c>file:native_name_encoding/0</c></seealso>).
+	The size of the encoded binary must be less than 2047 bytes.</p>
       </desc>
     </func>
     <func>
diff --git a/lib/kernel/src/heart.erl b/lib/kernel/src/heart.erl
index aa65c3a474..daed6dd488 100644
--- a/lib/kernel/src/heart.erl
+++ b/lib/kernel/src/heart.erl
@@ -184,14 +184,18 @@ wait_ack(Port) ->
 loop(Parent, Port, Cmd) ->
     _ = send_heart_beat(Port),
     receive
-	{From, set_cmd, NewCmd} when length(NewCmd) < 2047 ->
-	    _ = send_heart_cmd(Port, NewCmd),
-	    _ = wait_ack(Port),
-	    From ! {heart, ok},
-	    loop(Parent, Port, NewCmd);
-	{From, set_cmd, NewCmd} ->
-	    From ! {heart, {error, {bad_cmd, NewCmd}}},
-	    loop(Parent, Port, Cmd);
+	{From, set_cmd, NewCmd0} ->
+	    Enc = file:native_name_encoding(),
+	    case catch unicode:characters_to_binary(NewCmd0,Enc,Enc) of
+		NewCmd when is_binary(NewCmd), byte_size(NewCmd) < 2047 ->
+		    _ = send_heart_cmd(Port, NewCmd),
+		    _ = wait_ack(Port),
+		    From ! {heart, ok},
+		    loop(Parent, Port, NewCmd);
+		_ ->
+		    From ! {heart, {error, {bad_cmd, NewCmd0}}},
+		    loop(Parent, Port, Cmd)
+	    end;
 	{From, clear_cmd} ->
 	    From ! {heart, ok},
 	    _ = send_heart_cmd(Port, ""),