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

Subject: Re: ca_clear_channel() and "Network connection lost" messages
From: Jeff Hill <johill@lanl.gov>
To: William Lupton <wlupton@hapuna.keck.hawaii.edu>
Cc: tech-talk@aps.anl.gov
Date: Wed, 25 Sep 1996 18:23:17 -0600
William Lupton wrote:
> 
> Dear all,
> 
>   I have an application which (don't ask me why) performs a:
> 
> 1) ca_search()
> 2) ca_get() / ca_put()
> 3) ca_clear_channel()
> 
> sequence (with appropriate pends) when it wants to read or write a
> channel.
> 
>   This works fine under R3.12.0. Under R3.12.2 (and I don't think it's
> changed since) it still works fine, but if the channel count to an IOC
> ever goes to zero (which it does after each get or put) I get a "Network
> connection lost" message.
> 

This is a known bug in 3.12.2 (first reported by Nick Rees as I recall). 
I have not (so far) installed a patch into 3.12.2 because receiving a 
disconnect error message when the last channel is deleted should be benign 
(I have installed a fix into 3.13).

>   This appears to be because a ca_signal(ECA_DISCONN,...) call was added
> to base/src/ca/iocinf.c:close_ioc() at R3.12.2 (this routine is called
> when the channel count to an IOC goes to zero). Is there a reason for
> this and can I avoid these messages short of ensuring that I never allow
> the channel count to go to zero?
> 

The call to "ca_signal(ECA_DISCONN,...)" wasnt added to the code but was
instead moved outside of an if stmnt which checked to see if the channel
list was populated when entering "close_ioc()". As I recall this change
was a direct result of a patch added to purge resource identifiers out
of the system when an IOC disconnects.

If there is interest I will provide a patch for 3.12.2.

Jeff


-- 

______________________________________________________________________
Jeffrey O. Hill			Internet	johill@lanl.gov
LANL MS H820			Voice		505 665 1831
Los Alamos, NM 87545 USA 	FAX		505 665 5107


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ca_clear_channel() and "Network connection lost" messages William Lupton

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