RE: log message filter in Asyn

[Mark Rivers <rivers@cars.uchicago.edu>]

Note also that asyn messages can be turned off using medm or another OPI connected to an asyn record for that port.  Then you can selectively enable/disable each type of message (ASYN_TRACE_ERROR, ASYN_TRACE_FLOW, etc.).  That can be useful when messages are coming by so fast that it is hard to type on the console.

-----Original Message-----
From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-bounces@aps.anl.gov] On Behalf Of Andrew Johnson
Sent: Wednesday, April 18, 2012 3:07 PM
To: matthew.pearson@diamond.ac.uk
Cc: tech-talk@aps.anl.gov
Subject: Re: log message filter in Asyn

Hi Matt,

On 2012-04-18 matthew.pearson@diamond.ac.uk wrote:
> 
> The problem is is that we already have loads of drivers issuing messages
>  that they shouldn't do, so it would be good to have a solution that
>  doesn't involve modifying these. True, lots of the messages should be only
>  printed once. But there is a case for a driver repeating some kinds of
>  message at some slow rate, to inform the terminal that 'something is still
>  not right'. This gets round the problem of a single message being lost due
>  to some other printout going on.

Is the fundamental issue then that its hard to use the IOC console to debug or 
fix problems because of the volume of error messages you're getting?  That's 
what 'eltc 0' is for, it stops all the background error messages coming from 
Asyn perfectly for me.

Now if you can't use that because the IOC doesn't also send its errors to an 
iocLogServer and using 'eltc 0' would cause them to be lost completely, you 
could create an errlog listener which buffers (and possibly de-duplicates if 
you wish) the errlog messages into RAM.  You would provide your own command 
which turns on the buffer and calls eltc(0), and another one which prints out 
the stored messages, stops buffering and calls eltc(1) for when you're 
finished debugging.  See errlog.h and chapter 10 of the AppDevGuide for more 
details of the errlogAddListener() API.

HTH,

- Andrew
-- 
Never interrupt your enemy when he is making a mistake.
-- Napoleon Bonaparte