hi vineet2004

#Shell script 1:-
#!/usr/bin/ksh

while true
do
ksh run.ksh
sleep 5
done
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#Shell script 2:-
#!/usr/bin/ksh

echo "Hello World" >> $$.log
echo "Hello World1" >> $$.log
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In the above scripts , run.ksh is called by another script. the run.ksh creats the log file with the PID. and you want this log file to be processed by the perl script.
I assume that your log file will be created in some directory. For example :-
If your directory is /tmp/log_dir, then

perl parser.log `ls -rt /tmp/log_dir | tail -1`
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Once the log file is processed by your perl code then move the log file safely to the backup directory if you want or remove the log file, if you don't want the log file in future. Please customise the steps as per your requirement.