Table of Contents
Stability: 5 - Locked
All of the timer functions are globals. You do not need to
this module in order to use them.
setTimeout(callback, delay, [arg], [...])#
To schedule execution of a one-time
delay milliseconds. Returns a
timeoutId for possible use with
clearTimeout(). Optionally you can
also pass arguments to the callback.
It is important to note that your callback will probably not be called in exactly
delay milliseconds - Node.js makes no guarantees about the exact timing of when
the callback will fire, nor of the ordering things will fire in. The callback will
be called as close as possible to the time specified.
Prevents a timeout from triggering.
setInterval(callback, delay, [arg], [...])#
To schedule the repeated execution of
intervalId for possible use with
you can also pass arguments to the callback.
Stops a interval from triggering.
The opaque value returned by
setInterval also has the method
timer.unref() which will allow you to create a timer that is active but if
it is the only item left in the event loop won't keep the program running.
If the timer is already
unref again will have no effect.
In the case of
setTimeout when you
unref you create a separate timer that
will wakeup the event loop, creating too many of these may adversely effect
event loop performance -- use wisely.
If you had previously
unref()d a timer you can call
ref() to explicitly
request the timer hold the program open. If the timer is already
ref again will have no effect.
setImmediate(callback, [arg], [...])#
To schedule the "immediate" execution of
callback. Returns an
for possible use with
clearImmediate(). Optionally you can also pass
arguments to the callback.
Immediates are queued in the order created, and are popped off the queue once
per loop iteration. This is different from
process.nextTick which will
process.maxTickDepth queued callbacks per iteration.
will yield to the event loop after firing a queued callback to make sure I/O is
not being starved. While order is preserved for execution, other I/O events may
fire between any two scheduled immediate callbacks.
Stops an immediate from triggering.