curl-w32/docs/libcurl/opts/CURLOPT_DNS_LOCAL_IP4.md

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---
c: Copyright (C) Daniel Stenberg, <daniel.se>, et al.
SPDX-License-Identifier: curl
Title: CURLOPT_DNS_LOCAL_IP4
Section: 3
Source: libcurl
See-also:
- CURLOPT_DNS_INTERFACE (3)
- CURLOPT_DNS_LOCAL_IP6 (3)
- CURLOPT_DNS_SERVERS (3)
---
# NAME
CURLOPT_DNS_LOCAL_IP4 - IPv4 address to bind DNS resolves to
# SYNOPSIS
~~~c
#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
All
# EXAMPLE
~~~c
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);
}
}
~~~
# AVAILABILITY
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 7.33.0
# 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.