code: add error (res)

main.cpp

@@ -50,6 +50,11 @@ int main(int argc, char* argv[])
             curl_easy_setopt(curl, CURLOPT_URL, argv[1]);
             res = curl_easy_perform(curl);
             curl_easy_cleanup(curl);
+            if(res != 0)
+            {
+            cerr << curl_easy_strerror(res);
+            exit(1);
+            }
         }
     }
     bool prompt = true;