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From: Christian Robert <christian.robert@polymtl.ca>
To: John Alvord <jalvo@mbay.net>
Cc: linux-kernel@vger.kernel.org
Subject: Re: gettimeofday problem
Date: Tue, 25 Jun 2002 05:17:52 -0400	[thread overview]
Message-ID: <3D183540.6CA7CB00@sympatico.ca> (raw)
In-Reply-To: ecmfhuopshut8luclo6asqorsj4b1sa13q@4ax.com

John Alvord wrote:
> 
> Maybe this is the result of floating point rounding errors. Floating
> point is notorious for occaisional strange results. I suggest redoing
> the test program to keep all results in integer and seeing what
> happens...
> 
> john

You were close. 

Programming error on my part.

This modified subroutine does correct my test.
Notice the (LL) cast on 1000000

Computation was done on 32 bits integer then assign on the 64 bits integer.

sorry. 

ps: It may help explain the other > 1 hour time jump I've seen in an
    other thread.
 

LL GetTime (void)
{
  struct timeval tv;
  LL     retval;
  int    rc;

  while (0 != (rc = gettimeofday (&tv, NULL)))
    printf ("Wow! gettimeofday () returned %d\n", rc);

  retval = (tv.tv_sec * (LL)1000000) + (tv.tv_usec);

  return retval;
}

  reply	other threads:[~2002-06-25  9:17 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-06-25  0:37 gettimeofday problem Christian Robert
2002-06-25  0:43 ` Brad Hards
2002-06-25  2:03   ` Christian Robert
2002-06-25  2:47     ` John Alvord
2002-06-25  9:17       ` Christian Robert [this message]
2002-06-25 10:00         ` Jan Hudec
2002-07-19 12:17           ` Amos Waterland
2002-06-25 11:45   ` Richard B. Johnson
2002-06-25 11:50     ` Brad Hards
  -- strict thread matches above, loose matches on Subject: below --
2002-06-24  8:55 Salvatore D'Angelo
     [not found] ` <200206240934.g5O9YL524660@budgie.cs.uwa.edu.au>
2002-06-24 10:20   ` Salvatore D'Angelo
2002-06-24 12:46     ` Matti Aarnio
2002-06-24 13:57       ` Salvatore D'Angelo
2002-06-24 18:56         ` Karim Yaghmour
2002-06-26 11:01           ` Gabriel Paubert
2002-07-01  2:30         ` Pavel Machek
2002-07-01  2:29       ` Pavel Machek
2002-06-24 19:44     ` Richard B. Johnson
2002-06-24 23:34       ` Frank van de Pol
2002-06-25 11:42         ` Richard B. Johnson
2002-06-28 18:04           ` george anzinger
2002-06-25 13:36       ` Chris Friesen
2002-06-26 10:58         ` Gabriel Paubert

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