NAME

       CURLOPT_RESOLVE - provide custom host name to IP address resolves

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_RESOLVE,
                                 struct curl_slist *hosts);

DESCRIPTION

       Pass  a  pointer to a linked list of strings with host name resolve information to use for
       requests with this handle. The linked  list  should  be  a  fully  valid  list  of  struct
       curl_slist  structs  properly  filled  in. Use curl_slist_append(3) to create the list and
       curl_slist_free_all(3) to clean up an entire list.

       Each single name resolve string should be written using the format HOST:PORT:ADDRESS where
       HOST is the name libcurl will try to resolve, PORT is the port number of the service where
       libcurl wants to connect to the HOST and ADDRESS is the numerical IP address.  If  libcurl
       is built to support IPv6, ADDRESS can of course be either IPv4 or IPv6 style addressing.

       This option effectively pre-populates the DNS cache with entries for the host+port pair so
       redirects and everything that operations against  the  HOST+PORT  will  instead  use  your
       provided  ADDRESS.  Addresses  set  with CURLOPT_RESOLVE(3) will not time-out from the DNS
       cache like ordinary entries.

       The provided ADDRESS set by this option will be used even if CURLOPT_IPRESOLVE(3)  is  set
       to make libcurl use another IP version.

       Remove names from the DNS cache again, to stop providing these fake resolves, by including
       a string in the linked list that uses the format  "-HOST:PORT".  The  host  name  must  be
       prefixed  with  a  dash,  and  the  host  name and port number must exactly match what was
       already added previously.

       Support for providing the ADDRESS within [brackets] was added in 7.57.0.

DEFAULT

       NULL

PROTOCOLS

       All

EXAMPLE

       CURL *curl;
       struct curl_slist *host = NULL;
       host = curl_slist_append(NULL, "example.com:80:127.0.0.1");

       curl = curl_easy_init();
       if(curl) {
         curl_easy_setopt(curl, CURLOPT_RESOLVE, host);
         curl_easy_setopt(curl, CURLOPT_URL, "http://example.com");

         curl_easy_perform(curl);

         /* always cleanup */
         curl_easy_cleanup(curl);
       }

       curl_slist_free_all(host);

AVAILABILITY

       Added in 7.21.3. Removal support added in 7.42.0.

RETURN VALUE

       Returns CURLE_OK if the option is supported, and CURLE_UNKNOWN_OPTION if not.

SEE ALSO

       CURLOPT_IPRESOLVE(3), CURLOPT_DNS_CACHE_TIMEOUT(3), CURLOPT_CONNECT_TO(3),