curl/docs/examples/pop3-multi.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>
 * Get POP3 email using the multi interface
 * </DESC>
 */

#include <stdio.h>
#include <string.h>
#include <curl/curl.h>

/* This is a simple example showing how to retrieve mail using libcurl's POP3
 * capabilities. It builds on the pop3-retr.c example to demonstrate how to use
 * libcurl's multi interface.
 */

int main(void)
{
  CURL *curl;
  CURLM *mcurl;
  int still_running = 1;

  curl_global_init(CURL_GLOBAL_DEFAULT);

  curl = curl_easy_init();
  if(!curl)
    return 1;

  mcurl = curl_multi_init();
  if(!mcurl)
    return 2;

  /* Set username and password */
  curl_easy_setopt(curl, CURLOPT_USERNAME, "user");
  curl_easy_setopt(curl, CURLOPT_PASSWORD, "secret");

  /* This will retrieve message 1 from the user's mailbox */
  curl_easy_setopt(curl, CURLOPT_URL, "pop3://pop.example.com/1");

  /* Tell the multi stack about our easy handle */
  curl_multi_add_handle(mcurl, curl);

  do {
    CURLMcode mc = curl_multi_perform(mcurl, &still_running);

    if(still_running)
      /* wait for activity, timeout or "nothing" */
      mc = curl_multi_poll(mcurl, NULL, 0, 1000, NULL);

    if(mc)
      break;

  } while(still_running);

  /* Always cleanup */
  curl_multi_remove_handle(mcurl, curl);
  curl_multi_cleanup(mcurl);
  curl_easy_cleanup(curl);
  curl_global_cleanup();

  return 0;
}