I use this code in my scripts to process files inside a folder, but it only works for subfolders.
if [ -d "$1" ]; then for file in "${1%/}/"*/*(*.mkv|*.mp4|*.avi); do I know I can just remove /* to work with flat folders, but I'm looking for a more clean way to handle both flat folders ( no subfolders ) and folders with subfolders.
I have big code in the for loop so I don't want solutions that rely on find
Try globstar and extglob which is specific to bash
#!/usr/bin/env bash shopt -s globstar extglob if [[ -d $1 ]]; then for file in "$1"/**/*.@(mkv|mp4|avi); do : done fi 
extglob enable it and use bash *.@ seems to work, it was *@. that before. fi, how did you get that error message? bash code on some website like that, the code is not actually running on your machine. Your browser just sends the code off, it gets executed, and their web server sends the output back. It would be better if you tested your code on your own machine, in a terminal. I have big code in the for loop so I don't want solutions that rely on
find
If you change the for loop to a while loop and use read, it's easy to rely on find without further refactoring of what's inside the loop:
find "$1" -name "*.mkv" -o -name "*.mp4" -o -name "*.avi" -print0 | \ while read -d '' file; do # Process file done 