I'm trying to do what has to be a pretty common workflow:

1. Use `find` to build a list of files that I want to act on
2. Make a test of that list (e.g. that it's not empty)
3. Send that list to a command

How can I do this?

```
FILES=$(find $DIR -type f)
[ -z "$FILES" ] && exit 1
cmd "$FILES"

```

The `cmd` command doesn't seem to understand that `"$FILES"` is a list of arguments for it.