Experimental Physics and
Industrial Control System

"Artem Kazakov" <[email protected]> · Sat, 24 May 2008 10:18:58 +0900

Hi Andrew,

On Sat, May 24, 2008 at 4:49 AM, Andrew Johnson <[email protected]> wrote:
> If there is no caRepeater running on the machine, a CA client program will
> start one when it initializes the CA library.  The preferred method is to
> fork() and execlp() the external caRepeater program, but if it can't find
> caRepeater in $PATH the child process will print a warning and run the
> repeater functionality itself.  Do you have a copy of caRepeater in your
> $PATH?  I suspect not, and that if you did you'd find the zombie would not
> appear — please confirm that if possible.
Actually I do have caRepeater in my $PATH and therefore I do not see a
warning.  And if I remove it from  $PATH I start to see the warning
and caRepeater is not started and  zombie is not generated.

> What are the parent processes of the caRepeater and of the zombie?
Parent of the zombie is my script, and parent of the caRepeater is
zombie initially, but as soon as zombie becomes zombie
caRepeater is adopted by init (pid 1).
As it can be seen clearly from the following:
(Before caputackt becomes zombie - I just added sleep(60) before
return from main() to capture this)
USER    PID  PPID  PGID   SESS JOBC STAT   TT       TIME COMMAND
tyoma 15856 15164 15856 456b000    1 S+   s001    0:00.07 ruby ./runAllTests.rb
tyoma 15857 15856 15856 456b000    1 S+   s001    0:00.11
/Users/tyoma/epics/EpicsTest/bin/darwin-x86/common stcmd.host
tyoma 15869 15856 15856 456b000    1 S+   s001    0:00.24
/Users/tyoma/epics/EpicsTest/bin/darwin-x86/caputackt mrkai 0
tyoma 15870 15869 15856 456b000    1 S+   s001    0:00.01 caRepeater

(and here is zombie)
tyoma 15856 15164 15856 456b000    1 S+   s001    0:00.07 ruby ./runAllTests.rb
tyoma 15857 15856 15856 456b000    1 S+   s001    0:00.20
/Users/tyoma/epics/EpicsTest/bin/darwin-x86/common stcmd.host
tyoma 15869 15856 15856 456b000    1 Z+   s001    0:00.00 (caputackt)
tyoma 15870     1 15856 456b000    1 S+   s001    0:00.01 caRepeater

Artem

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System