[cs615asa] HW3-Time

[Chih-Yuan Lee]

Hi guys,

I have some questions about "Time". 

All my questions base on "how to get exactly time". I don't ask how to 
get localtime.  

About waiting time process, I have two ways to design the waiting time 
process. But they have different drawbacks. Please give me some 
suggestions.

Suppose: Waiting: 6 seconds.
               Localtime: start by 20th second.

The first way: Count second by second

It is because I count second by second. For this way, I need to count 
six times. 
For example,

start by 20....
21.22.23.24.25.26  ..stop

Drawback: 
If the system is reallly really slow during the script running, 
this way may miss one or two second. In fact, I have no chance to try 
this way on a machine that is really really slow. So that's just what I 
image.

For example,
start by 20....
21.22..{too slow and missing 23 } 24 25 26 27 ...stop
The exactly time should be stopped by 26th second.  

The second way: Intuition way
It is because the waiting time is 6 seconds. So the other processes 
will be started after 26th second (20+6).

Drawback:
If there is a  temporary failure happened at "26" second on the 
machine, it may miss the first 26th second. And the other processes 
will be started after the next 26th second.

For exampe:
start by 20.
21 22 23 24 25 {failure happened) 27 28 29 30.......0.1.2.....26(stop..)

Does anyone have any good idea for this???

Thanks,
Chih-Yuan Lee