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curl_multi_wakeup - wakes up a sleeping curl_multi_poll call #include <curl/curl.h> CURLMcode curl_multi_wakeup(CURLM *multi_handle); This function can be called from any thread and it wakes up a sleeping curl_multi_poll(3) call that is currently (or will be) waiting for activity or a timeout. If the function is called when there is no curl_multi_poll(3) call, it will cause the next call to return immediately. Calling this function only guarantees to wake up the current (or the next if there is no current) curl_multi_poll(3) call, which means it is possible that multiple calls to this function will wake up the same waiting operation. This function has no effect on curl_multi_wait(3) calls.

CURL *easy_handle;
CURLM *multi_handle;

/* add the individual easy handle */
curl_multi_add_handle(multi_handle, easy_handle);

/* this is thread 1 */
do {
 CURLMcode mc;
 int numfds;

 mc = curl_multi_perform(multi_handle, &still_running);

 if(mc == CURLM_OK) {
 /* wait for activity, timeout or wakeup */
 mc = curl_multi_poll(multi_handle, NULL, 0, 10000, &numfds);
 }

 if(time_to_die())
 exit(1);

} while(still_running);

curl_multi_remove_handle(multi_handle, easy_handle);

/* this is thread 2 */

if(something makes us decide to stop thread 1) {

 set_something_to_signal_thread_1_to_exit();

 curl_multi_wakeup(multi_handle);
}

Added in 7.68.0 CURLMcode type, general libcurl multi interface error code. curl_multi_poll "(3), " curl_multi_wait "(3)"