NAME

       CURLOPT_DNS_INTERFACE - interface to speak DNS over

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_DNS_INTERFACE, char *ifname);

DESCRIPTION

       Pass  a  char  pointer  as  parameter.  Set the name of the network interface that the DNS
       resolver should bind to. This must be an interface name (not an address). Set this  option
       to NULL to use the default setting (do not bind to a specific interface).

       The application does not have to keep the string around after setting this option.

       Using this option multiple times makes the last set string override the previous ones. Set
       it to NULL to disable its use again.

DEFAULT

       NULL

PROTOCOLS

       This functionality affects all supported 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_INTERFACE, "eth0");
           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

       Added in curl 7.33.0

RETURN VALUE

       Returns   CURLE_OK   if   the   option  is  supported,  CURLE_UNKNOWN_OPTION  if  not,  or
       CURLE_NOT_BUILT_IN if support was disabled at compile-time.

SEE ALSO

       CURLOPT_DNS_LOCAL_IP4(3),        CURLOPT_DNS_LOCAL_IP6(3),         CURLOPT_DNS_SERVERS(3),
       CURLOPT_INTERFACE(3)