How can i check if a directory/file in my for loop is empty?

Cook4733

11/3/23, 8:16 PM

So I have this following for loop that enters every directory and it that directory is empty it should leave it and do nothing. However if the directory isn't empty it should move its contents 1 place up and remove the remaining empty directory, but i dont know how to say: if [$i is empty] then ....

    for i in */*/
    do
      cd "$i"
    if [ -d "$i" ]
    then
        :
    else
        mv ./* ..
        cd -
        rmdir "$i"
    fi
done

100

1 + 1

bash

MDeBusk

11/3/23, 10:26 PM

Does something bad happen if you run the `mv` command on an empty directory?

Score:1

Ubuntu

steeldriver

11/3/23, 9:22 PM

You can expand the directory contents into an array (portably, using the shell's positional parameter array), then test how many elements it has, ex.

#!/bin/bash

shopt -s nullglob
for d in */; do
  set -- "$d"/*
  [ $# -gt 0 ] || continue
  printf '%s: is non-empty\n' "$d"
done

Change shopt -s nullglob to shopt -s nullglob dotglob if you want to include hidden files.

If you don't like using the positional parameter array, bash supports arrays more generally ex.

#!/bin/bash

shopt -s nullglob
for d in */; do
  files=( "$d"/* )
  [ ${#files[@]} -gt 0 ] || continue
  printf '%s: is non-empty\n' "$d"
done

+ 0

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