DOKK / manpages / debian 10 / libcurl4-doc / CURLOPT_RESOLVER_START_DATA.3.en
CURLOPT_RESOLVER_START_DATA(3) curl_easy_setopt options CURLOPT_RESOLVER_START_DATA(3)

CURLOPT_RESOLVER_START_DATA - custom pointer passed to the resolver start callback

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_RESOLVER_START_DATA, void *pointer);

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

NULL

All

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; } 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, "http://example.com");
curl_easy_perform(curl);
curl_easy_cleanup(curl); }

Added in 7.59.0

Returns CURLE_OK

CURLOPT_RESOLVER_START_FUNCTION(3)

February 14, 2018 libcurl 7.64.0