How would I search the memory of a process for a specific string?

Question

I'm interested in the basics. I have no idea where to begin with this. I've created this test program:

#include <stdio.h>

int main()
{
    char* test = "TEST04560";
    getchar();
    printf("%s\n", test);
}

The goal is to locate the memory address of "TEST04560" using an external program. I know how to use ReadProcessMemory and WriteProcessMemory but I don't know how to go about searching for a specific string in a program's memory. Any tips in the right direction are greatly appreciated.

Answer 1

What operating system? Most all OSes have some sort of "debugging" facility that allows you to observe/modify other processes (if you have permissions, of course).

On Linux, this is ptrace.

On Windows, there is ReadProcessMemory, and friends.

And for searching data of any type, there is memcmp. If you know how to use ReadProcessMemory, you certainly are familiar with this function.