while true do echo "1.Create files :"; echo "2.To Upper :"; echo "3.To Lower"; echo "4.Exit"; echo "Enter your choice : "; read ch; case $ch in 1) echo "Please enter File1 name : "; read dirr; touch $dirr.txt chmod 777 $dirr.txt echo "Open and write into $dirr.txt file manually" ;; 2) echo "Upper Case is: "; tr '[a-z]' '[A-Z]' < $dirr.txt #tr '[:lower:]' '[:upper:]' < $dirr.txt ;; 3) echo "Lower Case is: "; tr '[A-Z]' '[a-z]' < $dirr.txt #tr '[:upper:]' '[:lower:]' < $dirr.txt ;; 4) exit 0; ;; esac done #OUTPUT [root@localhost apcoer]# sh upper.sh 1.Create files : 2.To Upper : 3.To Lower 4.Exit Enter your choice : 1 Please enter File1 name : roro Open and write into roro.txt file manually 1.Create files : 2.To Upper : 3.To Lower 4.Exit Enter your choice : 2 Uppe...