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<== Date ==> <== Thread ==>
Subject: Re: How to safely implement an asynPortDriver with SCAN records
From: Michael Davidsaver via Tech-talk <tech-talk at aps.anl.gov>
To: Jure Varlec <jure.varlec at cosylab.com>
Cc: Érico Nogueira Rolim <erico.rolim at lnls.br>, tech-talk <tech-talk at aps.anl.gov>
Date: Wed, 20 Jul 2022 14:43:25 -0700 
On 7/20/22 11:51, Jure Varlec wrote:

 > imo. it is reasonable to join worker threads here, but I would

recommend against deleting.

Please keep in mind that delete leaves dangling pointers in the
asyn port.  imo. this is an invitation for the chaos of
use-after-free errors.


Could be, but I can't see how.


Ah, some Famous Last Words :)



The IOC is shutting down, asynManager is rejecting queueRequest calls to a disabled port


Which could be re-enabled.  And assuming that all code
actually respects the enabled switch.



(which is what the device support code uses), and asyn doesn't register any hooks that I can see.


Currently.



So AFAICT, when the records are the only users of the port, there should be no chaos.


As far as has been said, no.  This is an assumption through.

Actually, I should have mentioned before now the "atExitDebug"
global, which logs each exit hook before it runs.  I added this
after once being surprised by an exit hook I didn't know about.


var atExitDebug 1




Are you just trying to be careful,


In short, yes.

I'm trying to be careful and encourage what I see a good practice.
I certainly don't intend to jump on you in particular.

Tech-talk is an archived public mailing frequented by new(er)
users.  So in addition to Érico, I'm conscious of the audience.
Both now, and those whom google will later bring.



or are you aware of something I missed? If I'm wrong about this, I'd love to know before I have to face the chaos :) .

Best,
Jure
Replies:
Re: How to safely implement an asynPortDriver with SCAN records Jure Varlec via Tech-talk
References:
How to safely implement an asynPortDriver with SCAN records Érico Nogueira Rolim via Tech-talk
RE: How to safely implement an asynPortDriver with SCAN records Mark Rivers via Tech-talk
Re: How to safely implement an asynPortDriver with SCAN records Érico Nogueira Rolim via Tech-talk
Re: How to safely implement an asynPortDriver with SCAN records Andrew Johnson via Tech-talk
RE: How to safely implement an asynPortDriver with SCAN records Mark Rivers via Tech-talk
Re: How to safely implement an asynPortDriver with SCAN records Michael Davidsaver via Tech-talk
Re: How to safely implement an asynPortDriver with SCAN records Érico Nogueira Rolim via Tech-talk
Re: How to safely implement an asynPortDriver with SCAN records Jure Varlec via Tech-talk
Re: How to safely implement an asynPortDriver with SCAN records Michael Davidsaver via Tech-talk
Re: How to safely implement an asynPortDriver with SCAN records Jure Varlec via Tech-talk
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