timer.c File Reference

Monotonic timers, Linux timerfd(2) More...

#include <errno.h>
#include <sys/timerfd.h>
#include <unistd.h>
#include "uev.h"

Include dependency graph for timer.c:

Functions
int	uev_timer_init (uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int timeout, int period)
	Create and start a timer watcher. More...
int	uev_timer_set (uev_t *w, int timeout, int period)
	Reset a timer. More...
int	uev_timer_start (uev_t *w)
	Start a stopped timer watcher. More...
int	uev_timer_stop (uev_t *w)
	Stop and unregister a timer watcher. More...

Detailed Description

Monotonic timers, Linux timerfd(2)

Function Documentation

uev_timer_init()

int uev_timer_init	(	uev_ctx_t *	ctx,
		uev_t *	w,
		uev_cb_t *	cb,
		void *	arg,
		int	timeout,
		int	period
	)

Create and start a timer watcher.

Parameters

ctx	A valid libuEv context
w	Pointer to an uev_t watcher
cb	Callback function
arg	Optional callback argument
timeout	Timeout in milliseconds before cb is called
period	For periodic timers this is the period time that timeout is reset to

This function creates, and optionally starts, a timer watcher. There are two types of timers: one-shot and periodic.

One-shot timers only use timeout, period is zero.

Periodic timers can either start their life disabled, with timeout set to zero, or with the same value as period.

When the timeout expires, for either of the two types, cb is called, with the optional arg argument. A one-shot timer ends its life there, while a periodic task's timeout is reset to the period and restarted.

A timer is automatically started if the event loop is already running, otherwise it is kept on hold until triggered by calling uev_run().

See also

uev_timer_set

Returns

POSIX OK(0) or non-zero with errno set on error.

uev_timer_set()

int uev_timer_set	(	uev_t *	w,
		int	timeout,
		int	period
	)

Reset a timer.

Parameters

w	Watcher to reset
timeout	Timeout in milliseconds before cb is called, zero disarms timer
period	For periodic timers this is the period time that timeout is reset to

Note, the timeout value must be non-zero. Setting it to zero disarms the timer. This is the behavior of the underlying Linux function timerfd_settimer(2)

Returns

POSIX OK(0) or non-zero with errno set on error.

uev_timer_start()

int uev_timer_start

(

uev_t *

w

)

Start a stopped timer watcher.

Parameters

w	Watcher to start (again)

Returns

POSIX OK(0) or non-zero with errno set on error.

uev_timer_stop()

int uev_timer_stop

(

uev_t *

w

)

Stop and unregister a timer watcher.

Parameters

w	Watcher to stop

Returns

POSIX OK(0) or non-zero with errno set on error.