Checking from shell script if a directory contains

Question

From a shell script, how do I check if a directory contains files?

Something similar to this

if [ -e /some/dir/* ]; then echo "huzzah"; fi;

but which works if the directory contains one or several files (the above one only works with exactly 0 or 1 files).

Answer 1

to test a specific target directory

if [ -d $target_dir ]; then
    ls_contents=$(ls -1 $target_dir | xargs); 
    if [ ! -z "$ls_contents" -a "$ls_contents" != "" ]; then
        echo "is not empty";
    else
        echo "is empty";
    fi;
else
    echo "directory does not exist";
fi;

Answer 2

Works well for me this (when dir exist):

some_dir="/some/dir with whitespace & other characters/"
if find "`echo "$some_dir"`" -maxdepth 0 -empty | read v; then echo "Empty dir"; fi

With full check:

if [ -d "$some_dir" ]; then
  if find "`echo "$some_dir"`" -maxdepth 0 -empty | read v; then echo "Empty dir"; else "Dir is NOT empty" fi
fi

Answer 3

How about the following:

if find /some/dir/ -maxdepth 0 -empty | read v; then echo "Empty dir"; fi

This way there is no need for generating a complete listing of the contents of the directory. The read is both to discard the output and make the expression evaluate to true only when something is read (i.e. /some/dir/ is found empty by find).

Answer 4

So far I haven't seen an answer that uses grep which I think would give a simpler answer (with not too many weird symbols!). Here is how I would check if any files exist in the directory using bourne shell:

this returns the number of files in a directory:

ls -l <directory> | egrep -c "^-"

you can fill in the directory path in where directory is written. The first half of the pipe ensures that the first character of output is "-" for each file. egrep then counts the number of line that start with that symbol using regular expressions. now all you have to do is store the number you obtain and compare it using backquotes like:

 #!/bin/sh 
 fileNum=`ls -l <directory> | egrep -c "^-"`  
 if [ $fileNum == x ] 
 then  
 #do what you want to do
 fi

x is a variable of your choice.

Answer 5

Three best tricks

---

shopt -s nullglob dotglob; f=your/dir/*; ((${#f}))

This trick is 100% bash and invokes (spawns) a sub-shell. The idea is from Bruno De Fraine and improved by teambob's comment.

files=$(shopt -s nullglob dotglob; echo your/dir/*)
if (( ${#files} ))
then
  echo "contains files"
else 
  echo "empty (or does not exist or is a file)"
fi

Note: no difference between an empty directory and a non-existing one (and even when the provided path is a file).

There is a similar alternative and more details (and more examples) on the 'official' FAQ for #bash IRC channel:

if (shopt -s nullglob dotglob; f=(*); ((${#f[@]})))
then
  echo "contains files"
else 
  echo "empty (or does not exist, or is a file)"
fi

---

[ -n "$(ls -A your/dir)" ]

This trick is inspired from nixCraft's article posted in 2007. Add 2>/dev/null to suppress the output error "No such file or directory".
^{See also Andrew Taylor's answer (2008) and gr8can8dian's answer (2011).}

if [ -n "$(ls -A your/dir 2>/dev/null)" ]
then
  echo "contains files (or is a file)"
else
  echo "empty (or does not exist)"
fi

or the one-line bashism version:

[[ $(ls -A your/dir) ]] && echo "contains files" || echo "empty"

Note: ls returns $?=2 when the directory does not exist. But no difference between a file and an empty directory.

---

[ -n "$(find your/dir -prune -empty)" ]

This last trick is inspired from gravstar's answer where -maxdepth 0 is replaced by -prune and improved by phils's comment.

if [ -n "$(find your/dir -prune -empty 2>/dev/null)" ]
then
  echo "empty (directory or file)"
else
  echo "contains files (or does not exist)"
fi

a variation using -type d:

if [ -n "$(find your/dir -prune -empty -type d 2>/dev/null)" ]
then
  echo "empty directory"
else
  echo "contains files (or does not exist or is not a directory)"
fi

Explanation:

• find -prune is similar than find -maxdepth 0 using less characters
• find -empty prints the empty directories and files
• find -type d prints directories only

Note: You could also replace [ -n "$(find your/dir -prune -empty)" ] by just the shorten version below:

if [ `find your/dir -prune -empty 2>/dev/null` ]
then
  echo "empty (directory or file)"
else
  echo "contains files (or does not exist)"
fi

This last code works most of the cases but be aware that malicious paths could express a command...

Answer 6

# Works on hidden files, directories and regular files
### isEmpty()
# This function takes one parameter:
# $1 is the directory to check
# Echoes "huzzah" if the directory has files
function isEmpty(){
  if [ "$(ls -A $1)" ]; then
    echo "huzzah"
  else 
    echo "has no files"
  fi
}