Re: select(0,NULL,NULL,NULL,&t1) used for delay

On Thu, 2005-10-06 at 09:26 -0600, Christopher Friesen wrote:
> Alex Riesen wrote:
> 
> > Why don't you just use nanosleep(2) (or usleep)?
> 
> I can think of one main reason...existing code.  Also, nanosleep() 

And it's cooler to hack the kernel than to create and use a
portable_sleep() function and use it.

> rounds up excessively in many kernel versions, so that a request to 
> sleep for less than 1 tick ends up sleeping for 2 ticks.
                                                  ^^^^^^^

> The select() man page explicitly mentions this usage;
> 
> "Some code calls select with all three sets empty, n zero, and a 
> non-null timeout as a fairly portable way to sleep with subsecond 
                                                          ^^^^^^^^^
> precision."
  ^^^^^^^^^

You do realize that "subsecond precision" is probably meant as
improvement to sleep(3) and surely not to nanosleep(2)?

	Bernd
-- 
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