curl_multi_init - Man Page

#include <curl/curl.h>

CURLM *curl_multi_init();

This function returns a pointer to a CURLM handle to be used as input to all the other multi-functions, sometimes referred to as a multi handle in some places in the documentation. This init call MUST have a corresponding call to curl_multi_cleanup(3) when the operation is complete.

By default, several caches are stored in and held by the multi handle: DNS cache, connection pool, TLS session ID cache and the TLS CA cert cache. All transfers using the same multi handle share these caches.

This functionality affects all supported protocols

int main(void)
{
  /* init a multi stack */
  CURLM *multi = curl_multi_init();
  CURL *curl = curl_easy_init();
  CURL *curl2 = curl_easy_init();

  /* add individual transfers */
  curl_multi_add_handle(multi, curl);
  curl_multi_add_handle(multi, curl2);
}

Added in curl 7.9.6

If this function returns NULL, something went wrong and you cannot use the other curl functions.

curl_easy_init(3), curl_global_init(3), curl_multi_add_handle(3), curl_multi_cleanup(3), curl_multi_get_handles(3)

curl_easy_init(3), curl_multi_add_handle(3), curl_multi_cleanup(3), curl_multi_fdset(3), curl_multi_get_handles(3), curl_multi_info_read(3), curl_multi_perform(3), curl_multi_remove_handle(3), curl_multi_setopt(3), curl_multi_socket(3), curl_multi_socket_action(3), curl_multi_socket_all(3), libcurl-multi(3), libcurl-tutorial(3).