curl / libcurl / API / Examples / persistent.c

persistent.c

/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at https://curl.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 * SPDX-License-Identifier: curl
 *
 ***************************************************************************/
/* <DESC>
 * reusing handles to do HTTP persistent connections
 * </DESC>
 */
#include <stdio.h>
 
#include <curl/curl.h>
 
int main(void)
{
  CURL *curl;
 
  CURLcode result = curl_global_init(CURL_GLOBAL_ALL);
  if(result != CURLE_OK)
    return (int)result;
 
  curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
    curl_easy_setopt(curl, CURLOPT_HEADER, 1L);
 
    /* get the first document */
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
 
    /* Perform the request, result gets the return code */
    result = curl_easy_perform(curl);
    /* Check for errors */
    if(result != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s\n",
              curl_easy_strerror(result));
 
    /* get another document from the same server using the same
       connection */
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/docs/");
 
    /* Perform the request, result gets the return code */
    result = curl_easy_perform(curl);
    /* Check for errors */
    if(result != CURLE_OK)
      fprintf(stderr, "curl_easy_perform() failed: %s\n",
              curl_easy_strerror(result));
 
    /* always cleanup */
    curl_easy_cleanup(curl);
  }
 
  curl_global_cleanup();
 
  return (int)result;
}

Notice

This source code example is simplified and may ignore return codes and error checks. We do this to highlight the libcurl function calls and related options and reduce unrelated code.

A real-world application does of course properly check every return value and exit correctly at the first serious error.