xref: /curl/docs/examples/resolve.c (revision f540e43b)
1 /***************************************************************************
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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.
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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.
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18  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19  * KIND, either express or implied.
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21  * SPDX-License-Identifier: curl
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23  ***************************************************************************/
24 /* <DESC>
25  * Use CURLOPT_RESOLVE to feed custom IP addresses for given hostname + port
26  * number combinations.
27  * </DESC>
28  */
29 #include <stdio.h>
30 #include <curl/curl.h>
31 
main(void)32 int main(void)
33 {
34   CURL *curl;
35   CURLcode res = CURLE_OK;
36 
37   /* Each single name resolve string should be written using the format
38      HOST:PORT:ADDRESS where HOST is the name libcurl tries to resolve, PORT
39      is the port number of the service where libcurl wants to connect to the
40      HOST and ADDRESS is the numerical IP address
41    */
42   struct curl_slist *host = curl_slist_append(NULL,
43                                               "example.com:443:127.0.0.1");
44 
45   curl = curl_easy_init();
46   if(curl) {
47     curl_easy_setopt(curl, CURLOPT_RESOLVE, host);
48     curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
49     res = curl_easy_perform(curl);
50 
51     /* always cleanup */
52     curl_easy_cleanup(curl);
53   }
54 
55   curl_slist_free_all(host);
56 
57   return (int)res;
58 }
59