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Date: Fri, 17 Aug 2001 12:00:04 +0200
From: Markus Mottl <markus@mail4.ai.univie.ac.at>
To: caml-list@inria.fr
Subject: Re: [Caml-list] How to make a delay ?
Message-ID: <20010817120003.A19392@fichte.ai.univie.ac.at>
References: <20010817061534.A14359@darling.home.br>
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In-Reply-To: <20010817061534.A14359@darling.home.br>; from romildo@uber.com.br on Fri, Aug 17, 2001 at 06:15:34 -0300
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On Fri, 17 Aug 2001, Jos? Romildo Malaquias wrote:
> I am need to control the time under a program I am writing, in order
> to simulate a real-time situation. I just need a function that suspends
> the program execution for a given time, in miliseconds precision.

You can use timers and signals to do this, e.g.:

---------------------------------------------------------------------------
open Sys
open Unix
open Printf

let _ =
  set_signal sigalrm (Signal_handle (fun _ -> ()));
  let timer = 3.14159 in
  let expected_time = gettimeofday () +. timer in
  ignore (setitimer ITIMER_REAL { it_interval = 0.0; it_value = timer });
  pause ();
  printf "Precision: %f\n" (abs_float (gettimeofday () -. expected_time))
---------------------------------------------------------------------------

Depending on the type and load of your system, you can achieve precision
in the range of milliseconds.

Regards,
Markus Mottl

-- 
Markus Mottl                                             markus@oefai.at
Austrian Research Institute
for Artificial Intelligence                  http://www.oefai.at/~markus
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