topic Re: Getting pid and return code of the called script within script in Operating System - HP-UX

Getting pid and return code of the called script within script

Rui Vilao — Thu, 21 Apr 2005 06:56:58 GMT

Greetings,

I am writing a shell script in which I need to call another shell script.
However I need to check the pid and the return code of the called script.

I should look like as:

$WORKING_DIRECTORY/script.sh &
pid=$!
wait
ReturnCode=$?
...

My problem is that I am not able to get in ReturnCode the exit code of script.sh?

Any help/suggestion is highly appreciated.

Thanks in advance for your help,

Kind Regards,

Rui Vilao.

Re: Getting pid and return code of the called script within script

renarios — Thu, 21 Apr 2005 07:15:10 GMT

Hi Rui,

I created a same construction, only with functions.
In the function called in the background, I fill the variable PROG, which I monitor in the function below.
TIMEOUT=10
MAX_TIMEOUT=3600 #one hour
# Monitor the proces
while (( $(UNIX95= ps -xC $(basename ${PROG}) |grep ${ORACLE_SID} |wc -w) > 0 ))
do
# wait for the timeout period
sleep ${TIMEOUT}

# update counter with one
(( counter +=1 ))

# calculate total waiting time
(( wait_time=${counter}*${TIMEOUT} ))

# Show feedback as a dot every timeout time
printf "."

if (( ${wait_time} > ${MAX_TIMEOUT} ))
then
print "Killing ${ORACLE_SID} backup process after ${wait_time} seconds"
kill ${backup_process}
fi
done

Another possibility is to use the command jobs, i.e. :
while (( $(jobs | wc -l) > 0 ))
do
# wait for the timeout period
sleep ${TIMEOUT}

# update counter with one
(( counter +=1 ))

# calculate total waiting time
(( wait_time=${counter}*${TIMEOUT} ))

done

Hope it helps,

Renarios

Re: Getting pid and return code of the called script within script

Duncan Edmonstone — Thu, 21 Apr 2005 07:21:09 GMT

Rui,

First off, to be careful you should do this:

$WORKING_DIRECTORY/script.sh &
pid=$!
wait $pid
ReturnCode=$?

IIRC, one of the problems with the wait command is that it only returns the RC of the child process if it is executed *before* the script exits. Given the way UNIX functions, this will not necessarily be the case - (if script.sh exits very quickly for instance). \

In these situations I've always had my child processes write their status to a temp file which I can the read from the parent process - a kludge I know, but much more likely to work.

HTH

Duncan

Re: Getting pid and return code of the called script within script

Rui Vilao — Thu, 21 Apr 2005 08:07:53 GMT

Prblem solved thanks to Duncan & Renarios!

Cheers,

Rui.