HKEY hKey;
DWORD buffersize = 1024;
char* hldsloc = new char[buffersize];
RegOpenKeyEx (HKEY_CURRENT_USER,
"Software\\Valve\\HLServer",NULL,KEY_READ,&hKey);
RegQueryValueEx(hKey,"InstallPath",NULL,NULL,(LPBYTE) hldsloc,&buffersize);
RegCloseKey (hKey);