The PAGE_GUARD Anti-Dumping Trick

//http://waleedassar.blogspot.com - (@waleedassar)
//Code to show how to use the "PAGE_GUARD" anti-dumping trick.
#include "stdafx.h"
#include "windows.h"


#pragma data_seg("walied4")
int x=1;
#pragma data_seg()


int __stdcall watch()
{
    while(1)
    {
        MEMORY_BASIC_INFORMATION MBI={0};
        VirtualQuery(&x,&MBI,sizeof(MBI));
        if(!((MBI.Protect)&PAGE_GUARD)) ExitProcess(0);
    }
}

int main(int argc, char* argv[])
{
    unsigned long fake_base=(unsigned long)(&x);  //the page is initially PAGE_WRITECOPY
    *(unsigned long*)fake_base=0xCECECECE;        //Now it is PAGE_READWRITE
    unsigned long old;
    VirtualProtect((void*)fake_base,0x1000,PAGE_READWRITE|PAGE_GUARD,&old);
    unsigned long tid;
    CreateThread(0,0x1000,(LPTHREAD_START_ROUTINE)&watch,0,0,&tid);
    //---------------Useless stuff--------------
    MessageBox(0,"Try to dump me","waliedassar",0);
    ExitProcess(0);
    return 0;
}