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23 .TH CURLOPT_DNS_SERVERS 3 "May 31, 2017" "libcurl 7.59.0" "curl_easy_setopt options"
26 CURLOPT_DNS_SERVERS \- set preferred DNS servers
28 #include <curl/curl.h>
30 CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_SERVERS, char *servers);
32 Pass a char * that is the list of DNS servers to be used instead of the system
33 default. The format of the dns servers option is:
35 host[:port][,host[:port]]...
39 192.168.1.100,192.168.1.101,3.4.5.6
41 The application does not have to keep the string around after setting this
44 NULL - use system default
49 CURL *curl = curl_easy_init();
51 curl_easy_setopt(curl, CURLOPT_URL, "http://example.com/foo.bin");
52 curl_easy_setopt(curl, CURLOPT_DNS_SERVERS, "192.168.1.100:53,192.168.1.101");
53 ret = curl_easy_perform(curl);
54 curl_easy_cleanup(curl);
58 This option requires that libcurl was built with a resolver backend that
59 supports this operation. The c-ares backend is the only such one.
63 Returns CURLE_OK if the option is supported, CURLE_UNKNOWN_OPTION if not,
64 CURLE_NOT_BUILT_IN if support was disabled at compile-time,
65 CURLE_BAD_FUNCTION_ARGUMENT when given an invalid server list, or
66 CURLE_OUT_OF_MEMORY if there was insufficient heap space.
68 .BR CURLOPT_DNS_LOCAL_IP4 "(3), " CURLOPT_DNS_CACHE_TIMEOUT "(3), "