Tell Ruby Program to Wait some amount of time

Like this:

sleep(num_secs)

The num_secs value can be an integer or float.

Also, if you're writing this within a Rails app, or have included the ActiveSupport library in your project, you can construct longer intervals using the following convenience syntax:

sleep(4.minutes)
# or, even longer...
sleep(2.hours); sleep(3.days) # etc., etc.
# or shorter
sleep(0.5) # half a second

Use sleep like so:

sleep 2

That'll sleep for 2 seconds.

Be careful to give an argument. If you just run sleep, the process will sleep forever. (This is useful when you want a thread to sleep until it's woken.)

I find until very useful with sleep. example:

> time = Time.now
> sleep 2.seconds until Time.now > time + 10.seconds # breaks when true
> # or
> sleep 2 and puts 'still sleeping' until Time.now > time + 10
> # or
> sleep 1.seconds until !req.loading # suggested by ohsully