Help With A For Loop Issue

Shell Programming and Scripting
1

I was wondering how I can modify this for loop, so it only loops through the filenames that do not have an ".old" extension.

for filename in $(ls "$1")
do
   echo $filename | grep '\.old$' > /dev/null
   if [ $? != 0 ]
      then mv $1/$filename $1/$filename.old
   fi
done
2

one way to loop through is using grep:
eg
ls | grep -v ".old"
another way is using find
eg
find . -type f ! -name "*.old" -print

3

Do not use ls; it is unnnecessary and will break your script if any filenames contain spaces or other pathological characters.

for file in "$1"/*
do
  case $file in
     *.old) ;; ## do nothing
     *) mv "$file" "$file.old" ;;
  esac
done

You should probably also check that the new filename doesn't already exist.

4

Thanks for the replys I'll give those suggestions a try.

5 
for filename in $(ls "$1")
do
   [[ -d "$filename" || ${filename##*.} = "old" ]] || mv $1/$filename $1/$filename.old
done
6

Try that script on the directory TESTING after running these commands:

(
 mkdir TESTING
 cd TESTING
 touch "file one" "file two" "file three"
)