BRO...wait $! is probably not the right solution and it's not working also for this particular script

What I need is instead of sleep I want few lines of code which will check for the PID in the last line(tail -1) of current_date.log file in /abc/xyz directory....and check if the same PID count is 2 then it should execute the next job....

(Ex:- more Jan_12.log
Mon Jan 12 01:43:48 Program: saimptlogi: PID=12409: Started by rms
Mon Jan 12 01:45:50 Program: saimptlogi: PID=12409: Thread 1 - Terminated Successfully )

Please have a thorough look at my initial script and help me....I need these help badly...

Maybe this will help. Run tail on the log file, use perl to scan the output. When perl sees two lines with the same PID, it executes the command provided to perl on the rest of the command line.

tail -2f current_date.log | perl -ne '/PID=([0-9]+):/ && { $pid{$1}++; if ($pid{$1} >= 2) { exec(@ARGV); }' next-job arg1 arg2 ...

So instead of sleep 140 in the above mentioned script.....can I put it like this..will it work?:

cd $MMHOME/log
while
do
more $(ls -ltr|tail -1|cut -c 55-70)|grep "saimptlogi"|tail -2f|perl -ne '/PID=([0-9]+):/ && { $pid{$1}++; if ($pid{$1} >= 2)'
sleep 60
done

Um, no, because the tail won't exit with the -f option, and the PERL script won't exit by itself. (Also, you don't need "more" here). This is more what you're looking for

cd $MMHOME/log
logfile=$(ls -ltr|tail -1|cut -c 55-70)
if ! tail -2f $logfile |
        perl -ne '/saimptlogi/ && /PID=([0-9]+):/ && do { $pid{$1}++; exit 1 if ($pid{$1} >= 2) }'
then
        echo "Started"
fi

Sir....It is giving the following error.....

savouch_75002_20090210_20090226160640.out/appdb/product/agent/tmp/AAAjzaWJcsyntax error at -e line 1, near "; exit"
Execution of -e aborted due to compilation errors.
Started

PL/SQL procedure successfully completed.

/appdb/product/batch/rms/pos/RTLOG_GCN1.TXT
2
./saimptlogi_batch.sh[17]: ./saimptlogi: not found
syntax error at -e line 1, near "; exit"
Execution of -e aborted due to compilation errors.
Started

Also i think we should close { $pid{$1}++; exit 1 if ($pid{$1} >= 2)' .....with a } bracket ???

Right, I was missing the end bracket. That accounts for the error.

Thanks...I will test it and inform you abt the result....