curl/docs/libcurl/curl_multi_wakeup.3

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.TH curl_multi_wakeup 3 "17 Nov 2019" "libcurl" "libcurl"
.SH NAME
curl_multi_wakeup - wakes up a sleeping curl_multi_poll call
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLMcode curl_multi_wakeup(CURLM *multi_handle);
.fi
.SH DESCRIPTION
This function can be called from any thread and it wakes up a
sleeping \fIcurl_multi_poll(3)\fP call that is currently (or will be)
waiting for activity or a timeout.

If the function is called when there is no \fIcurl_multi_poll(3)\fP 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) \fIcurl_multi_poll(3)\fP 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 \fIcurl_multi_wait(3)\fP calls.
.SH EXAMPLE
.nf
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);
}

.fi
.SH AVAILABILITY
Added in 7.68.0
.SH RETURN VALUE
CURLMcode type, general libcurl multi interface error code.
.SH "SEE ALSO"
.BR curl_multi_poll "(3), " curl_multi_wait "(3)"