Shell Programming and Scripting

for f in /var/ww/vhost/*js; do 
  tac "$f" | 
    tail -n +4 |
      tac > "$f"_tmp_ && 
        mv -- "$f"_tmp_ "$f" 
done

 
#take backup first
cp -rf /var/ww/vhost/ /tmp/mybackup
 
for i in /var/ww/vhost/*js
do 
        printf '$-2,$d\nw\nq\n' | ed -s "$i"
done

cd /var/ww/vhost
ls -ltr *.js| grep -v '^d' | awk '{print$9}' > fileList
while read line
do
        nbrOfLines=`wc -l $line | awk '{print $1}'`
        minusThree=`expr $nbrOfLines - 3`
        head -$minusThree $line > new$line
done < fileList

#! /bin/bash

for x in `find vhost/ -type f -name "*.js"`
do
    total=$(wc -l < $x)
    from=$((total - 2))
    sed -i "$from,$total d" $x
done