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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Ravenscar vs selective wait
Date: Tue, 24 Mar 2015 20:12:33 +0000
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Date: 2015-03-24T20:12:33+00:00
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"J-P. Rosen" <rosen@adalog.fr> writes:

> Some hint however: I have a record containing a PO similar to what
> Jeff suggests, and a Timing_Event that unblocks the PO when the delay
> has expired. Similarly, the Wait entry has an out parameter to tell
> whether it's been awaken by an event or by time-out.

AdaCore's 4.9.1 implementation has a task which polls at 10 Hz
(adjustable by recompiling the RTS). The GPL 2014 arm-eabi version uses
magic deep in the System.BB (bare board) tree.

Whichever, it's clear that _something_ has to run every clock tick to
decide whether to invoke one of the timed events; and it seems best to
do it via a Timed_Event if I can get my FreeRTOS implementation to do
so.