Accessing the variable inside another code

Is there a way to access a variable initialized in one code inside another code. For eg my code1.c is as follows,

# include <stdio.h>
int main()
{
    int a=4;
    while(1);
    return 0;
}

Now, is there any way that I can access the the value of a from another C code? I am assuming I have all the knowledege of what is the variable which I have to get information for but I dont have the any information about its address in the RAM. So, is there any way?

I know about the extern, what I am asking for here is a sort of backdoor.