Shell Programming and Scripting

Hi all!

I have written a shell script which will invoke perl script infinitly in the background in a loop. Code will do as:Within while loop, perl script will be run in background, get the pid and notify pid in though mail. then wait for pid to be completed before going for next iteration. I am running the shell in background itself.

while [1] do
- invoke perl script in background
- get pid and mial
- wait for pid
- sent mail about job finining
- sleep for some time
done.

Exact Code:

Code:

set +o errexit
while [ 1 ]
do
# enter the optional parameter if we need to
        set -o monitor
        ${HOME}/${PROCESS}.pl ${OPTIONAL} 2>&1 > $LOGFILENAME &
        echo $! > ${PID_DIR}/${PROCESS}.perl
        chmod 755 ${PID_DIR}/${PROCESS}.perl
        cat ${PID_DIR}/${PROCESS}.perl | ${MAIL_BIN} -s "\"${MAIL_HEADING1}\"" ${MAIL_LIST}
        set +o monitor
        wait $!
        cat ${PID_DIR}/${PROCESS}.perl | ${MAIL_BIN} -s "\"${MAIL_HEADING2}\"" ${MAIL_LIST}
        sleep ${SLEEP}
done
exit 0

If run the shell in background then current shell is logging out but shell script and perl scripts are still running in background. Do you see any problem with code? Also I set the 'set +o errexit'. Why the script will exit suddenly? What are the other possible reasons?

Code:

 
misc/script> ./script.sh process1 option1&
[1] 1256
misc/script>
misc/script> exit
/>

Here is the OS info:

Code:

 
misc/script> uname -a
Linux servername 2.6.16.60-0.21-smp #1 SMP Tue May 6 12:41:02 UTC 2008 x86_64 x86_64 x86_64 GNU/Linux

Please help what I need to check? it very urgent. I am very new to linux env.

How far does it get?
Is there anything in $LOGFILENAME ?
Do you receive both emails ?

Does it work when invoked in foreground?


Also
If you intend to log out and leave the script running, you need "nohup".

Code:

nohup ./script.sh process1 option1 2>&1 >mylogfilename &