From: Tomas Pospisek's Mailing Lists <tpo2@...>
Date: 2007-03-02T07:57:06+09:00
Subject: Re: replacing the use of gettimeofday in the scheduler

On Thu, 1 Mar 2007, Tomas Pospisek's Mailing Lists wrote:

> Um. When I do a "timeout(5) { do_something };" and set the system clock back 
> by a minute, then the timeout will not *ever* time out.

Correction, sorry - it will sleep 1 minute + 5 seconds, so...
>
>>> But:
>>> 
>>> $ ri Kernel#sleep
>>>
>>>     Suspends the current thread for _duration_ seconds (which may be
>>>     any number, including a +Float+ with fractional seconds). Returns
>>>     the actual number of seconds slept (rounded), which may be less
>>>     than that asked for if another thread calls +Thread#run+. Zero
>>>     arguments causes +sleep+ to sleep forever.
>>> 
>>> No reference to wall-clock in there. What do you mean by "defined in terms 
>>> of the wall-clock"?
>> 
>> When I write "sleep 5" I expect at least five seconds on the clock on my 
>> wall to go by before the next statement is executed.
>
> That's right, However this will not happen, when you change the system time 
> while the 5 seconds have not gone by.

... it will not sleep as long as the wall-clock. I.e. will not do what I 
expect.
*t

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   Tomas Pospisek
   http://sourcepole.com -  Linux & Open Source Solutions
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