Select Code to Download

    # tail
    perl -ne '$i=$.%5; $a[$i]=$_; END{print @a[$i+1..$#a,0..$i]}' file
...
    perl -pe '$a[$i=$.%5]=$_}{print@a[$i+1..@a,0..$i]' file
    perl -pe '$_[$==$.%5]=$_}{print@_[$=+1..@_,0..$=]' file

    echo foo | perl -wpe 'your code here' file