CURLMOPT_TIMERDATA(3) Library Functions Manual CURLMOPT_TIMERDATA(3)

CURLMOPT_TIMERDATA - custom pointer to pass to timer callback

#include <curl/curl.h>
CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_TIMERDATA, void *pointer);

A data pointer to pass to the timer callback set with the CURLMOPT_TIMERFUNCTION(3) option.

This pointer is not touched by libcurl but is only be passed in to the timer callback's clientp argument.

NULL

This functionality affects all supported protocols

struct priv {
  void *custom;
};
static int timerfunc(CURLM *multi, long timeout_ms, void *clientp)
{
 struct priv *mydata = clientp;
 printf("our ptr: %p\n", mydata->custom);
 if(timeout_ms) {
   /* this is the new single timeout to wait for */
 }
 else {
   /* delete the timeout, nothing to wait for now */
 }
}
int main(void)
{
  struct priv mydata;
  CURLM *multi = curl_multi_init();
  curl_multi_setopt(multi, CURLMOPT_TIMERFUNCTION, timerfunc);
  curl_multi_setopt(multi, CURLMOPT_TIMERDATA, &mydata);
}

Added in curl 7.16.0

Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.

CURLMOPT_SOCKETFUNCTION(3), CURLMOPT_TIMERFUNCTION(3)

2024-09-18 libcurl