Hello Sean!

On 19 Dec 2024, Sean Dennis said the following...
 SD> ## Rename files
 SD> cd ./pics
 SD> for i in *.*; do
 SD>   new=$(printf "%04d.*" "${a}" #04 pad to length of 4
 SD>   mv -i -- "$i" "$new"
 SD>   ((a++))
 SD> done

How about this one (assuming bash as the shell):

a=0
while IFS= read -r -d $'\0' old; do
  new_path="${old%%/*}"
  new_name="${old##*/}"
  new_name="$(printf "%04d" "$a".${new_name##*.}"
  echo mv -i -- "$old" "${new_path}/${new_name}"
  ((a++))
done < <(find pics/ -xdev -mindepth 1 -maxdepth 1 -type f -print0)

(Remove the "echo" to activate.)

It will find files in the pics subdirectory -- only there, not deeper, and not
traversing into any other file systems -- and feed their full paths to the
while loop, separated by NUL characters. The while loop will extract the path
and the filename, and construct the new desired full path, using the padded
counter as the first part of the filename.

The process substitution/redirection feeding the while loop will ensure that no
command inside the while loop (e.g. the "mv" command) can interfere with its
input (e.g. interpreting a full path on the input as a user response to
overwriting a destination file that already exists).

The IFS stuff and the NUL separation should help for paths/filenames containing
(very) special characters.

Hope this helps, or at least sparks some ideas! =)

Best regards
Zip

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