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Top Forums UNIX for Advanced & Expert Users How to get the process id in to variable? Post 302441525 by Corona688 on Saturday 31st of July 2010 02:32:04 PM
Things are going to break all over the place here when the amount of data starts getting large. You shouldn't be cramming argument lists into backticks when you can possibly avoid it -- read arguments instead, from files or pipes. This also avoids needing to run cat at all, preventing much wasted CPU and I/O time. See Useless Use of Cat and Useless Use of Backticks.

# Save this instead of running lsvg over and over
lsvg -o | grep -v "rootvg" > /tmp/$$-lsvg
# "xargs command < filename" roughly equivalent to command `cat filename` but safer 
xargs lsvg -l < /tmp/$$-lsvg | awk '{ print $7 }' | grep -vE "(^$|LV|N/A)" | sort -r > ${LOGFLDR}/tmp_vg.out
        while read i
                        umount -f $i
                    if [ $? -ne 0 ]
                        fuser -kxuc $i
                        umount -f $i
                done < ${LOGFLDR}/tmp_vg.out

        while read i
                        varyoffvg $i
               done < /tmp/$$-lsvg

        rm -f /tmp/$$-lsvg
} 1>${LOGFLDR}/FS-status_daily.log 2>&1
if [ $? -eq 0 ]
d=`date +"%d-%m-%Y %H:%M"`
echo "Succefully Completed Execution of flashunmount.bash at $d "
unset d
exit 0
echo "Error Occured during the execution of flashunmount.bash. Refer the log file created in "${LOGFLDR}""

As for reading the PIDs, from man fuser:
       fuser  outputs  only  the  PIDs  to  stdout, everything else is sent to

...which makes this a lot easier.


# /tmp/$$-fuser is just a temporary file.  Use whatever name you please.
fuser -c /filesystem 2> /dev/null > /tmp/$$
while read -d ' ' P
        echo "PID is $P"
done < /tmp/$$-fuser
rm -f /tmp/$$-fuser

Last edited by Corona688; 07-31-2010 at 03:42 PM..
This User Gave Thanks to Corona688 For This Post:
Test Your Knowledge in Computers #480
Difficulty: Easy
Memory addresses are represented using hexadecimal, which is a base-8 counting system.
True or False?

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