Is ScriptX multithread-safe all the time?

[yqs112358]

Because of technical problems, in our project, a deteached thread is created to wait for messages posted to a Global engine, and this thread dispatch them to corresponding engines which handles data actually.
So I am curious that is it safe to call functions in a Different engine like engine->eval(xxx) or call function in Local<Function> generated from this Different engine when it is running other code at the same time , so-called "multithread-safe all the time".
Thanks very much! @LanderlYoung

[LanderlYoung]

A Local<> must be called in the engineScope that it blongs.

Engine scope itself holds lock, so it's safe to entet the same engine in different threadss.