typedef void (*flux_watcher_f)(flux_reactor_t *r, flux_watcher_t *w, int revents, void *arg);
flux_watcher_t *flux_timer_watcher_create (flux_reactor_t *r, double after, double repeat, flux_watcher_f callback, void *arg);
void flux_timer_watcher_reset (flux_watcher_t *w, double after, double repeat);
flux_timer_watcher_create() creates a flux_watcher_t object which
monitors for timer events. A timer event occurs when after seconds
have elapsed, and optionally again every repeat seconds.
When events occur, the user-supplied callback is invoked.
If after is 0., the flux_watcher_t will be immediately ready when the reactor is started. If repeat is 0., the flux_watcher_t will automatically be stopped when after seconds have elapsed.
Note that after is internally referenced to reactor time, which is only updated when the reactor is run/created, and therefore can be out of date. Use flux_reactor_now_update(3) to manually update reactor time before creating timer watchers in such cases. Refer to "The special problem of time updates" in the libev manual for more information.
To restart a timer that has been automatically stopped, you must reset
the after and repeat values with
The callback revents argument should be ignored.
Note: the Flux reactor is based on libev. For additional information
on the behavior of timers, refer to the libev documentation on
flux_timer_watcher_create() returns a flux_watcher_t object on success.
On error, NULL is returned, and errno is set appropriately.
Out of memory.