CURLOPT_DNS_SERVERS - DNS servers to use
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_SERVERS, char *servers);
Pass a char * that is the list of DNS servers to be used instead of the system
default. The format of the dns servers option is:
The application does not have to keep the string around after
setting this option.
NULL - use system default
CURL *curl = curl_easy_init();
curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/foo.bin");
curl_easy_setopt(curl, CURLOPT_DNS_SERVERS, "192.168.1.100:53,192.168.1.101");
ret = curl_easy_perform(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 7.24.0
Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not,
CURLE_NOT_BUILT_IN if support was disabled at compile-time,
CURLE_BAD_FUNCTION_ARGUMENT when given an invalid server list, or
CURLE_OUT_OF_MEMORY if there was insufficient heap space.