How to Test If a Directory Is Empty with Find

Bash command to see if any files in dir - test if a directory is empty

This is covered in detail in BashFAQ #004. Notably, use of ls for this purpose is an antipattern and should be avoided.

shopt -s dotglob   # if including hidden files is desired
files=( "$dir"/* )
[[ -e $files || -L $files ]] && echo "Directory is not empty"

[[ -e $files ]] doesn't actually check if the entire array's contents exist; rather, it checks the first name returned -- which handles the case when no files match, wherein the glob expression itself is returned as the sole result.

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Notably:

• This is far faster than invoking ls, which requires using fork() to spawn a subshell, execve() to replace that subshell with /bin/ls, the operating system's dynamic linker to load shared libraries used by the ls binary, etc, etc. [An exception to this is extremely large directories, of tens of thousands of files -- a case in which ls will also be slow; see the find-based solution below for those].
• This is more correct than invoking ls: The list of files returned by globbing is guaranteed to exactly match the literal names of files, whereas ls can munge names with hidden characters. If the first entry is a valid filename, "${files[@]}" can be safely iterated over with assurance that each returned value will be a name, and there's no need to worry about filesystems with literal newlines in their names inflating the count if the local ls implementation does not escape them.

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That said, an alternative approach is to use find, if you have one with the -empty extension (available both from GNU find and from modern BSDs including Mac OS):

[[ $(find -H "$dir" -maxdepth 0 -type d -empty) ]] || echo "Directory is not empty"

...if any result is given, the directory is nonempty. While slower than globbing on directories which are not unusually large, this is faster than either ls or globbing for extremely large directories not present in the direntry cache, as it can return results without a full scan.

Finding empty directories

Check whether find <dir> -type f outputs anything. Here's an example:

for dir in A B C; do
    [ -z "`find $dir -type f`" ] && echo "$dir is empty"
done

How do I check if a folder has contents?

You can check if a directory is empty using find, and processing its output:

#!/bin/sh
target=$1
if find "$target" -mindepth 1 -print -quit 2>/dev/null | grep -q .; then
    echo "Not empty, do something"
else
    echo "Target '$target' is empty or not a directory"
fi

That is:

• Use find to find the first filesystem entry under $target (-mindepth 1), print it (-print), and stop processing (-quit)
  
  
  • Redirect stderr to suppress any error messages (= noise)
• Check if the output of the find command is empty using grep -q .
  
  • grep -q . will exit after processing at most one character. If it sees a character it exits with success, if it doesn't (its input is empty) then it exits with failure.
• If the output of the find command is not empty, then the directory is not empty, and grep -q . exits with success.
• If the output of the find command is empty, then $target is either an empty directory, or not a directory (does not exist), and grep -q . exits with failure.

The reason we have to rely on the stdout of find rather than its own exit code directly is that there's no way to make the find command use distinguishable exit codes in case files were found or not.

Instead of piping to grep -q, another alternative would be to capture the output of find and check if it's an empty string or not.

#!/bin/sh
target=$1
if [ "$(find "$target" -mindepth 1 -print -quit 2>/dev/null)" ]; then
    echo "Not empty, do something"
else
    echo "Target '$target' is empty or not a directory"
fi

Capturing command output like this uses a sub-shell.
I think the solution using grep is probably faster,
but I haven't tested it.

PHP: What is the best and easiest way to check if directory is empty or not

Use glob :

if (count(glob("path/*")) === 0 ) { // empty

A nice thing about glob is that it doesn't return . and .. directories.

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