does c++ standard prohibit the void main() prototype?

Question

In section 3.6.1.2 of both C++ Standard 1998 and 2003 editions,

An implementation shall not predefine the main function. This function shall not be overloaded. It shall have a return type of type int, but otherwise its type is implementation-defined.

I am not a native English speaker.I do not sure what does"but otherwise" means.Whether it is to prohibit the other return type,or to give the right to C++ compiler writer?

So what's the answer?

Answer 1

The english you quote does prohibit declaring main to return void. It is allowing variation in the arguments that come in, but not in the return type.