curl/docs/libcurl/opts/CURLINFO_ACTIVESOCKET.md
Daniel Stenberg 5a488251f7
curldown: fixups
- make DEFAULT sections less repetitive

- make historic mentions use HISTORY

- generate the protocols section on `# %PROTOCOLS%` instead of guessing
  where to put it

- generate the availability section on `# %AVAILABILITY%` instead of
  guessing where to put it

- make the protocols section more verbose

Closes #14227
2024-07-19 17:03:25 +02:00

2.0 KiB

c SPDX-License-Identifier Title Section Source See-also Protocol Added-in
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
7.45.0

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 If the socket is no longer valid, CURL_SOCKET_BAD is returned.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.

%PROTOCOLS%

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

    /* Extract the socket from the curl handle */
    res = curl_easy_getinfo(curl, CURLINFO_ACTIVESOCKET, &sockfd);
    if(!res && sockfd != CURL_SOCKET_BAD) {
      /* operate on sockfd */
    }

    curl_easy_cleanup(curl);
  }
}

%AVAILABILITY%

RETURN VALUE

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