Shell Programming and Scripting

while getopts ":h" Option
do
        case $Option in
          h     ) display_help;;
        esac
done

while getopts ":h" Option
do
    case $Option in
        h     ) display_help ;;
    esac
done
shift $((OPTIND-1))
NUMBER=$1

#!/bin/ksh
# This script is used to monitor the traffic results from simulator and nodes on a regular interval
# The reports are saved at a common directory

function display_help
{
echo " Usage: \"monitor_traffic intervaltime totaltime\" "
echo " intervaltime - The intervals you want the report to be collected in minutes "
echo " totaltime - The time the whole traffic session runs in hours "
echo " Example: ./monitor_traffic 60 8 (where the reports are collected for every 60 minutes for 8 hours) "
}

if [ "$1" = "" ]
then
display_help
exit 1
fi

while getopts ":h" Option
do
case $Option in
h ) display_help;;
esac
done

shift $(($OPTIND - 1))

exit 0

# Converting the minutes to seconds
interval=`expr $1 \* 60`
totaltime=`expr $2 \* 60 \* 60`
a=`expr $interval`
echo "Test"
while [ $a -le $totaltime ]
do
sleep $interval
echo "Test"
a=`expr $a + $interval`
done

scriptname -h -x -y 89
# or
scriptname -hxy 89
# where x and y are the other options. Note that you can put arguments to the options. 
scriptname -t 300 # where 300 is the value for the t option.
# Must be written in the script like (suppose you have h, t, x and y)
while getopts ":ht:xy" Option
# Note the ':' after 't' : Option requires an argument
do
    case $Option in
        h     ) display_help;;
        t) T=$OPTARG ;; # puts the argument in variable T
        x) process x ;;
        y) process y ;;
    esac
done
shift $(($OPTIND - 1))