code: cerr errors

main.cpp

@@ -43,6 +43,10 @@ int main(int argc, char* argv[])
             CURLcode res;
             curl_easy_setopt(curl, CURLOPT_URL, argv[1]);
             res = curl_easy_perform(curl);
+            if (res!=CURLE_OK){
+                cerr << curl_easy_strerror(res);
+                exit(1);
+            }
             curl_easy_cleanup(curl);
         }
         return 0;