Tag: INTERNET_OPTION_USER_AGENT

This is a clear case of …. uhmm got no clue. All I know is that I’ve tried in quite a few different ways to use the InternetQueryOption API function to retrieve the default User Agent and all have failed. The internet contains posts about other people also not being able to retrieve the User Agent…so I got really frustrated. Finally decided to just retrieve the User Agent the old fashioned way, by directly talking to the registry. So here is a quick function to do that:

/*
 Returns a pointer to the useragent string.
 Return NULL if something goes wrong.
 do NOT forget to free it!
*/
char *getUA(){
 LONG res;
 HKEY regopen;
 char *ua;
 DWORD type;
 DWORD size = 80;

 ua = (char *)malloc(80);
 SecureZeroMemory(ua,80);
 res = RegOpenKeyEx(HKEY_CURRENT_USER, TEXT("Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings"),0,KEY_QUERY_VALUE,&regopen);
 if(res == ERROR_SUCCESS){
 res = RegQueryValueEx(regopen,TEXT("User Agent"),0,&type,(BYTE *)ua,&size);
 if(res == ERROR_SUCCESS){
 RegCloseKey(regopen);
 return ua;
 }
 }
 free(ua);
 return NULL;
}