Shell Programming and Scripting

Hey guys I have to make a script that takes one argument, the name of a directory, and adds the extension ".old" to all visible files in the directory that don't already have it.

I made one that loops through the file names and uses a grep to see if the extension .old is there and then renames it like this:

Code:

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

Now I have to Use a for loop to go through the filenames in the directory. But, only loop through the filenames that do not have a ".old" extension. Inside this loop I have to rename the file to the new name. Anyone have any idea how I would do this?

Code:

 
find $1 -maxdepth 1 -type f   -not -name "*.old" -exec mv {} {}.old \;

Code:

 
find $1 -maxdepth 1 -type f -not -name "*.old" | xargs -i{} mv {} {}.old

does this go inside the for loop?

could use -v option of grep command to exclude .old files.And those curly braces are important when you append any letter or word (here: .old)

Code:

for filename in $(ls * | grep -v '\.old$' 2> /dev/null)
do
	#echo $filename | grep -v '\.old$' 2> /dev/null
	
	mv "${filename}" "${filename}.old"
done

No, You don't need loop. either one-liner can do the job.

Code:

for filename in "$1"/*
do
  if [ -f "$filename" ] && [ ! -e "$filename.old" ]; then
    mv "$filename" "$filename.old"
  fi 
done