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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: An Example for Ada.Execution_Time
Date: Fri, 31 Dec 2010 22:40:32 +0000
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Simon Wright <simon@pushface.org> writes:

> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

>> I think this is the core of misunderstanding. The thing you have in
>> mind is "time interval since the task start according to the
>> execution time clock."  It is not Ada.Execution_Time.Clock, it is:
>>
>>    Ada.Execution_Time.Clock - CPU_Time_First
>
> I don't _think_ that CPU_Time_First is actually defined as the value
> of Clock when the task starts (is initialized, put on the ready queue,
> whatever).

I think (from having had a look at GNAT GPL 2010's sources) that you are
right to suggest Time_Of (0) in place of CPU_Time_First (in GNAT's
implementation, the latter is Duration'First!).

Or Niklas's suggestion of the missing CPU_Time_Zero.