curl / libcurl / API / Examples / sepheaders.c

sepheaders.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>
 * Simple HTTP GET that stores the headers in a separate file
 * </DESC>
 */
#ifdef _MSC_VER
#ifndef _CRT_SECURE_NO_WARNINGS
#define _CRT_SECURE_NO_WARNINGS  /* for fopen() */
#endif
#endif
 
#include <stdio.h>
#include <stdlib.h>
 
#include <curl/curl.h>
 
static size_t write_cb(char *ptr, size_t size, size_t nmemb, void *stream)
{
  size_t written = fwrite(ptr, size, nmemb, (FILE *)stream);
  return written;
}
 
int main(void)
{
  CURL *curl;
 
  CURLcode result = curl_global_init(CURL_GLOBAL_ALL);
  if(result != CURLE_OK)
    return (int)result;
 
  /* init the curl session */
  curl = curl_easy_init();
  if(curl) {
    static const char *headerfilename = "head.out";
    FILE *headerfile;
    static const char *bodyfilename = "body.out";
    FILE *bodyfile;
 
    /* set URL to get */
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
 
    /* no progress meter please */
    curl_easy_setopt(curl, CURLOPT_NOPROGRESS, 1L);
 
    /* send all data to this function */
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_cb);
 
    /* open the header file */
    headerfile = fopen(headerfilename, "wb");
    if(!headerfile) {
      curl_easy_cleanup(curl);
      curl_global_cleanup();
      return -1;
    }
 
    /* open the body file */
    bodyfile = fopen(bodyfilename, "wb");
    if(!bodyfile) {
      curl_easy_cleanup(curl);
      fclose(headerfile);
      curl_global_cleanup();
      return -1;
    }
 
    /* we want the headers be written to this file handle */
    curl_easy_setopt(curl, CURLOPT_HEADERDATA, headerfile);
 
    /* we want the body be written to this file handle instead of stdout */
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, bodyfile);
 
    /* get it! */
    result = curl_easy_perform(curl);
 
    /* close the header file */
    fclose(headerfile);
 
    /* close the body file */
    fclose(bodyfile);
 
    /* cleanup curl stuff */
    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.