Re: Killing a soft IOC which doesn't have an interactive shell

[David Kline <dkline@aps.anl.gov>]

nick,

i've been using screen on the ebricks 
(http://www.aps.anl.gov/bcda/ebrick/index.php) for quite sometime now
and haven't seen any problems. it is nice to be able to attach/detach 
to/from an iocsh at will (simultaneous
connections as well), in addition to a log file being produced that 
shows the history of what commands were
issued. startup/shutdown is easily done with a single command from a 
linux shell prompt.
cheers,
/david

Rees, Nick (DLSLtd,RAL,DIA) wrote:
> We have a need to run IOC's on Linux without a stdin and are looking for
> the best way to set this up. The IOC's are to be used in a test harness
> so need to be run up and down automatically and repeatedly.
>
> The obvious thing to do was to duplicate what is done with the "softIoc
> -s" command, which is to execute the startup script and then call
> epicsThreadExitMain. The problem is that once epicsThreadExitMain is
> called the process shows up as <defunct> and doesn't respond to normal
> signals and only dies with a kill -9.
>
> The solutions we can think of are:
>
> 1. Wrap the IOC in screen or procServ and so it has a stdin
> 2. Don't call epicsThreadExitMain, but install a signal handler that
> gives a semaphore and then takes the semaphore.
> 3. Use kill -9 to kill the IOC.
>
> Is there a recommended way to do this? In many ways, option 2 seems
> best, but there should be an Epics call that does that for us. I don't
> know of one, but would be happy to contribute one if it was supported.
>
> Cheers,
>
> Nick Rees
> Principal Software Engineer           Phone: +44 (0)1235-778430
> Diamond Light Source                  Fax:   +44 (0)1235-446713
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+-------------------------------------------------+
David M. Kline                   dkline@aps.anl.gov
Beamline Controls and Data Acquisition (BCDA)
Argonne National Laboratory, Advanced Photon Source
Argonne IL, 60439                      630.252.8639
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         Beamlines R Us -- EBRICKs Rule
+-------------------------------------------------+