Скрипт выполняет задачу не до конца

#!/bin/sh
mv_files() { # source, dest
    ls -l "$1" | sed -ne 's/  / /g;s/^-//p' | cut -d' ' -f 9- | while read file; do
        rm -rf "$2/$file"
        mv -f "$1/$file" "$2"
    done
}
if [ -d "$1" ] && [ -d "$2" ]; then
    tmp="$(mktemp -d)"
    mv_files "$1" "$tmp"
    mv_files "$2" "$1"
    mv_files "$tmp" "$2"
    rmdir "$tmp"
else
    echo 'Directory is not found.' >&2
    exit 1
fi