Here's how you might implement a counter:
counter=0
while true; do
if /home/hadoop/latest/bin/hadoop fs -ls /apps/hdtech/bds/quality-rt/dt=$DATE_YEST_FORMAT2 then
echo "Files Present" | mailx -s "File Present" -r [email protected] [email protected]
exit 0
elif [[ "$counter" -gt 20 ]]; then
echo "Counter: $counter times reached; Exiting loop!"
exit 1
else
counter=$((counter+1))
echo "Counter: $counter time(s); Sleeping for another half an hour" | mailx -s "Time to Sleep Now" -r [email protected] [email protected]
sleep 1800
fi
done
Some Explanations:
counter=$((counter+1)) - this is how you can increment a counter. The $ for counter is optional inside the double parentheses in this case.elif [[ "$counter" -gt 20 ]]; then - this checks whether $counter is not greater than 20. If so, it outputs the appropriate message and breaks out of your while loop.