NAME

CURLOPT_RESOLVER_START_DATA - pointer passed to the resolver start callback

SYNOPSIS

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_RESOLVER_START_DATA,


                          void *pointer);

DESCRIPTION

Pass a pointer is be untouched by libcurl and passed as the third argument in the resolver start callback set with CURLOPT_RESOLVER_START_FUNCTION(3).

DEFAULT

NULL

PROTOCOLS

This functionality affects all supported protocols

EXAMPLE

static int resolver_start_cb(void *resolver_state, void *reserved,


                             void *userdata)
{


  (void)reserved;


  printf("Received resolver_state=%p userdata=%p\n",


         resolver_state, userdata);


  return 0;
}
int main(void)
{


  CURL *curl = curl_easy_init();


  if(curl) {


    curl_easy_setopt(curl, CURLOPT_RESOLVER_START_FUNCTION, resolver_start_cb);


    curl_easy_setopt(curl, CURLOPT_RESOLVER_START_DATA, curl);


    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");


    curl_easy_perform(curl);


    curl_easy_cleanup(curl);


  }
}

AVAILABILITY

Added in curl 7.59.0

RETURN VALUE

curl_easy_setopt(3) returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).