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User talk:Dmitry-kazakov: Difference between revisions
Some explanations
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end;
They look like they are masking/ignoring the ''Out_Of_Ink'' exception.
:Yes, this is on the server side. When an exception is propagated out of an entry point, that happens both on the server and the client sides. In our case the server just ignores it. The client ends. --[[User:Dmitry-kazakov|Dmitry-kazakov]] 08:32, 19 February 2009 (UTC)
Whereas program appears to propagate ''Out_Of_Ink'' back to ''Mother_Goose''. e.g.
requeue Backup.Print with abort;
Is that because of the ''with abort''?
:''with abort'' means that it is allowed for the client to cancel the rendezvous request while it waits in the queue of ''Backup''. If ''Mother_Goose'' have used a timed entry call:
<blockquote>
<lang ada>
select
Main.Print (...);
or delay 5.0;
Put_Line ("No response from the printer");
end select;
</lang>
</blockquote>
:then if the rendezvous to ''Backup'' would not engaged in 5 seconds (including the waiting time for ''Main'') then it would output "No response from the printer". --[[User:Dmitry-kazakov|Dmitry-kazakov]] 08:32, 19 February 2009 (UTC)
Also: when the task is requeued, does the ''Main'' printer suspend
waiting for ''Backup'' to finish? (Or is the exception propagated directly
back from ''Backup'' to ''Mother_Goose'' without passing through ''Main'')
:No, the server ''Main'' continues when the entry point body is left, the client (say ''Mother_Goose'') stay blocked and waits now for the new server ''Backup'' to service the rendezvous. --[[User:Dmitry-kazakov|Dmitry-kazakov]] 08:32, 19 February 2009 (UTC)
ThanX
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