How to rename all files in a directory and subdirectories? - bash

Question

I'm trying to access all files in a directory and it's subdirectories; and I'm trying to implement this code for it to work:
#!/bin/bash
NEWNAME="newFile"
echo "- - - - - - - - - - - "
for f in *\ *; do mv "$f" "${f// /_}"; done
for f in *.* *; do mv "$f" "${f// /_}"; done
FILES=$(find ./ -type f)
for f in $FILES; do
path=$(dirname "${f}")
extension="${f##*.}"
echo $extension;
mv "$f" "${f/$f/${$path/$NEWNAME.$extension}}"
done
But my lack of knowledge in bash results in this error:
mv: rename * * to *_*: No such file or directory
mv: rename very_important_folder to very_important_folder/very_important_folder: Invalid argument
//very_important_folder/bob
./app.sh: line 13: ${$path/$NEWNAME.$extension}: bad substitution
This my folder setup:
-very important folder:
-|filewithoutspaces.py
-|anothersubfolder:
--|file with spaces.txt
-app.sh
And so, I'm trying to change all the files in the directories 1 name: newname, but leaving the extension as it was. I encountered problems changing files with spaces in their names, and I'm not really familiar with bash.
It does change the files not in folders, but it doesn't work for the ones in subdirectories.
I'm using MacBook Air (M1, 2020) macOS 12.3 Monterey.

Answer 1

I'm not sure about what you really wanna do but the following construct can surely help you:
#!/bin/bash
shopt -s globstar
for path in ./**
do
[[ -d "$path" ]] && continue
[[ $path =~ ^(.*/)([^/]+)(\.[^/]*)$|^(.*/)(.+)$ ]]
dirpath="${BASH_REMATCH[1]}${BASH_REMATCH[4]}"
filename="${BASH_REMATCH[2]}${BASH_REMATCH[5]}"
extension="${BASH_REMATCH[3]}"
echo mv "$path" "$dirpath${filename// /_}$extension"
done
notes:
shopt -s globstar allows the glob ** to match any path length.
./** is for making sure that there is at least one / in the resulting paths. It simplifies greatly the splitting of a path into its different components.
[[ -d "$path" ]] && continue means to skip paths that are directories.
[[ $path =~ ... ]] is a bash way of using a regex for splitting the path into dirname filename and extension.
echo ... Now that you have the different components of the filepath at hand, you can do whatever you want.
Update
As a workaround for older bash you can define a function and call it in find:
#!/bin/bash
doit() {
local path dirpath filename extension
for path
do
[[ $path =~ ^(.*/)([^/]+)(\.[^/]*)$|^(.*/)(.+)$ ]]
dirpath="${BASH_REMATCH[1]}${BASH_REMATCH[4]}"
filename="${BASH_REMATCH[2]}${BASH_REMATCH[5]}"
extension="${BASH_REMATCH[3]}"
echo mv "$path" "$dirpath${filename// /_}$extension"
done
}
export -f doit
find . -type f -exec bash -c 'doit "$0" "$#"' {} +
Just be aware that if you use an external variable inside the function (like NEWNAME in your code), you'll also have to export it: export NEWNAME="newFile".
BTW, it's not safe to capitalise your shell variables.