**************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
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*
* Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
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* are also available at https://curl.haxx.se/docs/copyright.html.
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* furnished to do so, under the terms of the COPYING file.
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**************************************************************************

CURLINFO_ACTIVESOCKET - get the active socket #include <curl/curl.h> CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_ACTIVESOCKET, curl_socket_t *socket); Pass a pointer to a curl_socket_t to receive the active socket used by this curl session. If the socket is no longer valid, CURL_SOCKET_BAD is returned. When you finish working with the socket, you must call curl_easy_cleanup(3) as usual on the easy handle and let libcurl close the socket and cleanup other resources associated with the handle. This is typically used in combination with CURLOPT_CONNECT_ONLY(3). This option was added as a replacement for CURLINFO_LASTSOCKET(3) since that one isn't working on all platforms. All

CURL *curl = curl_easy_init();
if(curl) {
 curl_socket_t sockfd;
 curl_easy_setopt(curl, CURLOPT_URL, "http://example.com");

 /* Do not do the transfer - only connect to host */
 curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 1L);
 res = curl_easy_perform(curl);

 /* Extract the socket from the curl handle */
 res = curl_easy_getinfo(curl, CURLINFO_ACTIVESOCKET, &sockfd);

 if(res != CURLE_OK) {
 printf("Error: %s\\n", curl_easy_strerror(res));
 return 1;
 }
}

Added in 7.45.0 Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not. curl_easy_getinfo "(3), " curl_easy_setopt "(3), " CURLINFO_LASTSOCKET "(3), "