CURLOPT_DNS_SERVERS
Section: curl_easy_setopt options (3)
Updated: November 04, 2020
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NAME
CURLOPT_DNS_SERVERS - set preferred DNS servers
SYNOPSIS
#include <
curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_SERVERS, char *servers);
DESCRIPTION
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:
host[:port][,host[:port]]...
For example:
192.168.1.100,192.168.1.101,3.4.5.6
The application does not have to keep the string around after setting this
option.
DEFAULT
NULL - use system default
PROTOCOLS
All
EXAMPLE
CURL *curl = curl_easy_init();
if(curl) {
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);
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 7.24.0
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,
CURLE_BAD_FUNCTION_ARGUMENT when given an invalid server list, or
CURLE_OUT_OF_MEMORY if there was insufficient heap space.
SEE ALSO
CURLOPT_DNS_LOCAL_IP4(3),
CURLOPT_DNS_CACHE_TIMEOUT(3),