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<== Date ==> <== Thread ==>

Subject: Re: Arbitrary limit on timeouts?
From: "Johnson, Andrew N." <anj@aps.anl.gov>
To: Eric Norum <wenorum@lbl.gov>
Cc: EPICS mailing list <tech-talk@aps.anl.gov>
Date: Wed, 7 Jun 2017 19:33:34 +0000
My guess is that the 3600 second timeout might have been thought of as an arbitrary limit intended to avoid wrapping, but this is for the Posix implementation only and I don’t see where such limits would apply anyway. The convertDoubleToWakeTime() routine *only* appears to be used in the Posix implementation of epicsEventWaitWithTimeout(), and since the wakeTime is an absolute time anyway I think we can safely remove the limit.

I will do this in 3.14 and merge up, unless someone objects.

- Andrew



> On Jun 7, 2017, at 1:44 PM, Eric Norum <wenorum@lbl.gov> wrote:
> 
> Thanks for checking the provenance of this.
> I can see the usefulness of the sanity check limit to non-negative timeouts but the arbitrary upper limit seems like a bad idea. Maybe it’s too late to change now — there may be some existing code that depends on this.   At the very least the behaviour should be noted in the application developers guide.  
> 
>> On Jun 7, 2017, at 10:38 AM, Michael Davidsaver <mdavidsaver@gmail.com> wrote:
>> 
>> On 06/07/2017 06:50 PM, Eric Norum wrote:
>>> Why are timeouts for things like epicsEventWaitWithTImeout() limited to
>>> 1 hour?
>>> This is for R3.15.4, but I suspect the code is the same in lots of versions.
>> 
>> Since at least 2000 (first occurrence I find).  The commit message
>> doesn't give any clues.
>> 
>> https://github.com/epics-base/epics-base/commit/8c60195f4b463bff42f6f967da8bc19d6f5ad11d#diff-583652b37e7f98cf7b720e489744ce88R57
>> 
>> Seems rather arbitrary, so I think this could be removed (or enlarged).
> 


References:
Arbitrary limit on timeouts? Eric Norum
Re: Arbitrary limit on timeouts? Michael Davidsaver
Re: Arbitrary limit on timeouts? Eric Norum

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