Linux Command Line and....ch18（select函数？）

function diskspace {
clear
df -k
}

function whoseon {
clear
who
}

function memusage {
clear
cat /proc/meminfo
}

PS3="Enter option: "
select option in "Display disk space" "Display logged on users" "Display memory usage" "Exit program"
do
case $option in
"Exit program")
break ;;
"Display disk space")
diskspace ;;
"Display logged on users")
echo "Monday";;
"Display memory usage")
memusage ;;
*)
clear
echo "Sorry, wrong selection";;
esac
done
clear

#!/bin/bash
# using a variable to hold the list
function diskspace {
clear
df -k
}

function whoseon {
clear
who
}

function memusage {
clear
cat /proc/meminfo
}

function menu {
clear
echo
echo -e "\t\t\tSys Admin Menu\n"
echo -e "\t1. Display disk space"
echo -e "\t2. Display logged on users"
echo -e "\t3. Display memory usage"3
echo -e "\t0. Exit program\n\n"
echo -en "\t\tEnter option: "
read -n 1 option

}
while [ 1 ]
do
menu
case $option in
0)
break ;;
1)
diskspace ;;
2)
whoseon ;;
3)
memusage ;;
*)
clear
echo "Sorry, wrong selection";;
esac
echo -en "\n\n\t\t\tHit any key to continue"
read -n 1 line
done
clear