Re: GPS Leap Second Scheduled!

[Chris Wedgwood <chris@cybernet.co.nz>]

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On Thu, Sep 10, 1998 at 11:45:15AM +1200, Chris Wedgwood wrote:

> The attached code on a PPro 200 gives me results of 2 usecs, using a
> P.II 300 and SYSENTER semantics, you can probably get this to less
> that 1usec.

Crap... here it is.



-cw

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#include <sys/time.h>
#include <unistd.h>
#include <stdio.h>

int	main()
{
	struct timeval	t1,t2,t3,t4;
	
	do{
		/* warm caches */
		gettimeofday(&t1,NULL);
		gettimeofday(&t2,NULL);
		gettimeofday(&t3,NULL);
		gettimeofday(&t4,NULL);

		gettimeofday(&t3,NULL);
		gettimeofday(&t4,NULL);
	}while(t3.tv_sec != t4.tv_sec); /* yuk */

	printf("%d usecs difference!\n",(int)(t4.tv_usec - t3.tv_usec));
	
	
	return	0;
}