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From: Robert A Duff <bobduff@world.std.com>
Subject: Re: Ada Tasks vs Linux processes
Sender: bobduff@world.std.com (Robert A Duff)
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Date: Mon, 2 Apr 2001 18:00:18 GMT
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Date: 2001-04-02T18:00:18+00:00
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tmoran@acm.org writes:

>   LRM D.9(7) says the implementation must document the minimum delay
> value that actually causes the task to block, while D.9(5) says a
> delay of zero does not block, but is only "potentially blocking".
> Even among compilers that don't implement Annex D, delay 0.0 usually
> does not unnecessarily block, while any positive delay usually blocks
> for two clock ticks, which on some systems can be a surprisingly long
> time.

Right, but "delay 0.0;" will cause the task to go to the end of its
ready queue, so if there's any other task of the same priority waiting
to run, it will run.  So "delay 0.0;" does what some systems call
"yield".  (Assuming Annex D.)

- Bob