curl/docs/libcurl/opts/CURLINFO_ACTIVESOCKET.md
Daniel Stenberg e3fe020089
docs/libcurl: generate PROTOCOLS from meta-data
Remove the PROTOCOLS section from the source files completely and
instead generate them based on the header data in the curldown files.

It also generates TLS backend information for options marked for TLS as
protocol.

Closes #13175
2024-03-23 18:13:03 +01:00

1.9 KiB

c SPDX-License-Identifier Title Section Source See-also Protocol
Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. curl CURLINFO_ACTIVESOCKET 3 libcurl
CURLINFO_LASTSOCKET (3)
CURLOPT_CONNECT_ONLY (3)
curl_easy_getinfo (3)
curl_easy_setopt (3)
All

NAME

CURLINFO_ACTIVESOCKET - get the active socket

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_ACTIVESOCKET,
                           curl_socket_t *socket);

DESCRIPTION

Pass a pointer to a curl_socket_t to receive the most recently active socket used for the transfer connection by this curl session. If the socket is no longer valid, CURL_SOCKET_BAD is returned. When you are finished 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 option returns the active socket only after the transfer is complete, and is typically used in combination with CURLOPT_CONNECT_ONLY(3), which skips the transfer phase.

CURLINFO_ACTIVESOCKET(3) was added as a replacement for CURLINFO_LASTSOCKET(3) since that one is not working on all platforms.

EXAMPLE

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_socket_t sockfd;
    curl_easy_setopt(curl, CURLOPT_URL, "https://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;
    }
  }
}

AVAILABILITY

Added in 7.45.0

RETURN VALUE

Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.