CURLOPT_DNS_LOCAL_IP6 - Man Page

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_LOCAL_IP6, char *address);

Set the local IPv6 address that the resolver should bind to. The argument should be of type char * and contain a single IPv6 address as a string. Set this option to NULL to use the default setting (do not bind to a specific IP address).

The application does not have to keep the string around after setting this option.

NULL

This functionality affects all supported protocols

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/foo.bin");
    curl_easy_setopt(curl, CURLOPT_DNS_LOCAL_IP6, "fe80::a9ff:fe46:b619");
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

This option requires that libcurl was built with a resolver backend that supports this operation. The c-ares backend is the only such one.

Added in curl 7.33.0

Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not, CURLE_NOT_BUILT_IN if support was disabled at compile-time, or CURLE_BAD_FUNCTION_ARGUMENT when given a bad address.

CURLOPT_DNS_INTERFACE(3), CURLOPT_DNS_LOCAL_IP4(3), CURLOPT_DNS_SERVERS(3)

curl_easy_setopt(3), CURLOPT_DNS_INTERFACE(3), CURLOPT_DNS_LOCAL_IP4(3), CURLOPT_DNS_SERVERS(3), libcurl-symbols(3).