curl/docs/libcurl/opts/CURLOPT_DNS_LOCAL_IP4.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

1.5 KiB

c SPDX-License-Identifier Title Section Source See-also Protocol Added-in
Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al. curl CURLOPT_DNS_LOCAL_IP4 3 libcurl
CURLOPT_DNS_INTERFACE (3)
CURLOPT_DNS_LOCAL_IP6 (3)
CURLOPT_DNS_SERVERS (3)
All
7.33.0

NAME

CURLOPT_DNS_LOCAL_IP4 - IPv4 address to bind DNS resolves to

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_LOCAL_IP4, char *address);

DESCRIPTION

Set the local IPv4 address that the resolver should bind to. The argument should be of type char * and contain a single numerical IPv4 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.

DEFAULT

NULL

%PROTOCOLS%

EXAMPLE

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_IP4, "192.168.0.14");
    res = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

NOTES

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

%AVAILABILITY%

RETURN VALUE

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.