OllyDbg "STARTF_FORCEOFFFEEDBACK" trick

//http://waleedassar.blogspot.com - (@waleedassar)
//This old trick works against OllyDbg v1.10 and v2.x
#include "windows.h"

int main(int argc, char* argv[])
{
    STARTUPINFO SINFO={sizeof(STARTUPINFO)};
    GetStartupInfo(&SINFO);

    if(SINFO.dwFlags&STARTF_FORCEOFFFEEDBACK)
    {
                  MessageBox(0,"Olly detected",0,0);
    }
    else
    {
          MessageBox(0,"Okay","waliedassar",0);
    }
    return 0;
}