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Updated: Thursday, June 13, 2019
 
 

CURLMOPT_TIMERFUNCTION (3)

Name

CURLMOPT_TIMERFUNCTION - set callback to receive timeout values

Synopsis

#include <curl/curl.h>

int timer_callback(CURLM *multi,    /* multi handle */
long timeout_ms, /* see above */
void *userp);    /* private callback pointer */

CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_TIMERFUNCTION, timer_callback);

Description

CURLMOPT_TIMERFUNCTION(3)  curl_multi_setopt options CURLMOPT_TIMERFUNCTION(3)



NAME
       CURLMOPT_TIMERFUNCTION - set callback to receive timeout values

SYNOPSIS
       #include <curl/curl.h>

       int timer_callback(CURLM *multi,    /* multi handle */
                          long timeout_ms, /* see above */
                          void *userp);    /* private callback pointer */

       CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_TIMERFUNCTION, timer_callback);

DESCRIPTION
       Pass a pointer to your callback function, which should match the proto-
       type shown above.

       Certain features, such as timeouts and retries,  require  you  to  call
       libcurl even when there is no activity on the file descriptors.

       Your  callback  function  timer_callback should install a non-repeating
       timer with an interval of timeout_ms. Each time that timer fires,  call
       either  curl_multi_socket_action(3) or curl_multi_perform(3), depending
       on which interface you use.

       A timeout_ms value of -1 means you should delete your timer.

       A    timeout_ms    value    of    0    means    you     should     call
       curl_multi_socket_action(3)  or curl_multi_perform(3) (once) as soon as
       possible.

       timer_callback will only be called when the timeout_ms changes.

       The userp pointer is set with CURLMOPT_TIMERDATA(3).

       The timer callback should return 0 on success, and -1  on  error.  This
       callback  can  be  used instead of, or in addition to, curl_multi_time-
       out(3).

DEFAULT
       NULL

PROTOCOLS
       All

EXAMPLE
       static gboolean timeout_cb(gpointer user_data)
       {
         int running;
         if(user_data) {
           g_free(user_data);
           curl_multi_setopt(curl_handle, CURLMOPT_TIMERDATA, NULL);
         }
         curl_multi_socket_action(multi, CURL_SOCKET_TIMEOUT, 0, &running);
         return G_SOURCE_REMOVE;
       }

       static int timerfunc(CURLM *multi, long timeout_ms, void *userp)
       {
         guint *id = userp;

         if(id)
           g_source_remove(*id);

         /* -1 means we should just delete our timer. */
         if(timeout_ms == -1) {
           g_free(id);
           id = NULL;
         }
         else {
           if(!id)
             id = g_new(guint, 1);
           *id = g_timeout_add(timeout_ms, timeout_cb, id);
         }
         curl_multi_setopt(multi, CURLMOPT_TIMERDATA, id);
         return 0;
       }

       curl_multi_setopt(multi, CURLMOPT_TIMERFUNCTION, timerfunc);

AVAILABILITY
       Added in 7.16.0

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


ATTRIBUTES
       See attributes(7) for descriptions of the following attributes:


       +---------------+------------------+
       |ATTRIBUTE TYPE | ATTRIBUTE VALUE  |
       +---------------+------------------+
       |Availability   | web/curl         |
       +---------------+------------------+
       |Stability      | Uncommitted      |
       +---------------+------------------+
SEE ALSO
       CURLMOPT_TIMERDATA(3), CURLMOPT_SOCKETFUNCTION(3),



NOTES
       This     software     was    built    from    source    available    at
       https://github.com/oracle/solaris-userland.   The  original   community
       source    was    downloaded    from    https://github.com/curl/curl/ar-
       chive/curl-7_64_0.zip

       Further information about this software can be found on the open source
       community website at http://curl.haxx.se/.



libcurl 7.37.0                    17 Jun 2014        CURLMOPT_TIMERFUNCTION(3)