1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at https://curl.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24 /* <DESC>
25 * Extract headers post transfer with the header API
26 * </DESC>
27 */
28 #include <stdio.h>
29 #include <curl/curl.h>
30
write_cb(char * data,size_t n,size_t l,void * userp)31 static size_t write_cb(char *data, size_t n, size_t l, void *userp)
32 {
33 /* take care of the data here, ignored in this example */
34 (void)data;
35 (void)userp;
36 return n*l;
37 }
38
main(void)39 int main(void)
40 {
41 CURL *curl;
42
43 curl = curl_easy_init();
44 if(curl) {
45 CURLcode res;
46 struct curl_header *header;
47 curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
48 /* example.com is redirected, so we tell libcurl to follow redirection */
49 curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L);
50
51 /* this example just ignores the content */
52 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_cb);
53
54 /* Perform the request, res gets the return code */
55 res = curl_easy_perform(curl);
56 /* Check for errors */
57 if(res != CURLE_OK)
58 fprintf(stderr, "curl_easy_perform() failed: %s\n",
59 curl_easy_strerror(res));
60
61 if(CURLHE_OK == curl_easy_header(curl, "Content-Type", 0, CURLH_HEADER,
62 -1, &header))
63 printf("Got content-type: %s\n", header->value);
64
65 printf("All server headers:\n");
66 {
67 struct curl_header *h;
68 struct curl_header *prev = NULL;
69 do {
70 h = curl_easy_nextheader(curl, CURLH_HEADER, -1, prev);
71 if(h)
72 printf(" %s: %s (%u)\n", h->name, h->value, (int)h->amount);
73 prev = h;
74 } while(h);
75
76 }
77 /* always cleanup */
78 curl_easy_cleanup(curl);
79 }
80 return 0;
81 }
82
