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sleep [Function]

sleep seconds => nil

Arguments and Values::

seconds--a non-negative real.

Description::

Causes execution to cease and become dormant for approximately the seconds of real time indicated by seconds, whereupon execution is resumed.

Examples::

      (sleep 1) =>  NIL
     
     ;; Actually, since SLEEP is permitted to use approximate timing,
     ;; this might not always yield true, but it will often enough that
     ;; we felt it to be a productive example of the intent.
      (let ((then (get-universal-time))
            (now  (progn (sleep 10) (get-universal-time))))
        (>= (- now then) 10))
     =>  true
     

Side Effects::

Causes processing to pause.

Affected By::

The granularity of the scheduler.

Exceptional Situations::

Should signal an error of type type-error if seconds is not a non-negative real.