Shell Programming and Scripting

 echo $x | sed -ne 's/\([0-9]\{2\}\) - .* - .*[0-9]\{3\}\.mp3/track\1.mp3/gp'

#!/bin/bash
FS=$'\n'
for x  in *.mp3
do
 var="`echo -ne $x | sed -ne 's/\([0-9]\{2\}\) - .* - .*[0-9]\{3\}\.mp3/track\1.mp3/gp' `"
 cp "$x" "$var"
done
unset IFS

var="`echo -ne $x | sed -ne 's/\([0-9]\{2\}\) - .* - .*[0-9]\{3\}\.mp3/track\1.mp3/gp' 
is not the same thing like i did before
var="`sed -ne 's/\([0-9]\{2\}\) - .* - .*[0-9]\{3\}\.mp3/track\1.mp3/gp' "$x"`"

echo "$IFS" | od -c