how to pass variable argument to exe?

Question

Okay, let's say that I have b.exe, which takes a string argument. I want to invoke b.exe within a.cpp, with system:

    string s1 = "hallo";
    system("b.exe s1");
    printf("s1 after invoke = %s",s1);

and this is the code in b.cpp:

    int main(string s)
    {
         s = "hello world";
         return 0; 
    }

what I want is, when I run a.exe, the output will be:

    s1 after invoke = hello world

is it possible to do that? basically, i just want to pass a variable to an exe, but it must be by reference, not only by value because I want that variable to be processed and modified within the exe that I invoked. I've already searched the solution on the internet, but it only provides me tha way to pass a variable by value to the exe, not by reference..

any suggestion will be very appreciated, but if possible, I want the suggestion in the form of the above correction code and include files, if any. thanks for your help :)

Answer 1

It is not possible to modify command line arguments among different processes. s1 is known only to A.CPP, and s is only known to B.CPP.