如何检查目录是否存在于 Bash shell 脚本中？

Question

What command checks if a directory exists or not within a Bash shell script?

Answer 1

To check if a directory exists in a shell script, you can use the following:

if [ -d "$DIRECTORY" ]; then
  # Control will enter here if $DIRECTORY exists.
fi

Or to check if a directory doesn't exist:

if [ ! -d "$DIRECTORY" ]; then
  # Control will enter here if $DIRECTORY doesn't exist.
fi

---

However, as Jon Ericson points out, subsequent commands may not work as intended if you do not take into account that a symbolic link to a directory will also pass this check. Eg running this:

ln -s "$ACTUAL_DIR" "$SYMLINK"
if [ -d "$SYMLINK" ]; then 
  rmdir "$SYMLINK" 
fi

Will produce the error message:

rmdir: failed to remove `symlink': Not a directory

So symbolic links may have to be treated differently, if subsequent commands expect directories:

if [ -d "$LINK_OR_DIR" ]; then 
  if [ -L "$LINK_OR_DIR" ]; then
    # It is a symlink!
    # Symbolic link specific commands go here.
    rm "$LINK_OR_DIR"
  else
    # It's a directory!
    # Directory command goes here.
    rmdir "$LINK_OR_DIR"
  fi
fi

---

Take particular note of the double-quotes used to wrap the variables. The reason for this is explained by 8jean in another answer .

If the variables contain spaces or other unusual characters it will probably cause the script to fail.

Answer 2

Remember to always wrap variables in double quotes when referencing them in a Bash script. Kids these days grow up with the idea that they can have spaces and lots of other funny characters in their directory names. (Spaces! Back in my days, we didn't have no fancy spaces! ;))

One day, one of those kids will run your script with $DIRECTORY set to "My M0viez" and your script will blow up. You don't want that. So use this.

if [ -d "$DIRECTORY" ]; then
    # Will enter here if $DIRECTORY exists, even if it contains spaces
fi

Answer 3

Note the -d test can produce some surprising results:

$ ln -s tmp/ t
$ if [ -d t ]; then rmdir t; fi
rmdir: directory "t": Path component not a directory

File under: "When is a directory not a directory?" The answer: "When it's a symlink to a directory." A slightly more thorough test:

if [ -d t ]; then 
   if [ -L t ]; then 
      rm t
   else 
      rmdir t
   fi
fi

You can find more information in the Bash manual on Bash conditional expressions and the [ builtin command and the [[ compound commmand .

Answer 4

I find the double-bracket version of test makes writing logic tests more natural:

if [[ -d "${DIRECTORY}" && ! -L "${DIRECTORY}" ]] ; then
    echo "It's a bona-fide directory"
fi

Answer 5

Shorter form:

# if $DIR is a directory, then print yes
[ -d "$DIR" ] && echo "Yes"

Answer 6

1. A simple script to test if a directory or file is present or not:

    if [ -d /home/ram/dir ] # For file "if [ -f /home/rama/file ]" then echo "dir present" else echo "dir not present" fi

2. A simple script to check whether the directory is present or not:

    mkdir tempdir # If you want to check file use touch instead of mkdir ret=$? if [ "$ret" == "0" ] then echo "dir present" else echo "dir not present" fi

   The above scripts will check if the directory is present or not

   $? if the last command is a success it returns "0", else a non-zero value. Suppose tempdir is already present. Then mkdir tempdir will give an error like below:

   mkdir: cannot create directory 'tempdir': File exists

Answer 7

To check if a directory exists you can use a simple if structure like this:

if [ -d directory/path to a directory ] ; then
# Things to do

else #if needed #also: elif [new condition]
# Things to do
fi

You can also do it in the negative:

if [ ! -d directory/path to a directory ] ; then
# Things to do when not an existing directory

Note : Be careful. Leave empty spaces on either side of both opening and closing braces.

With the same syntax you can use:

-e: any kind of archive

-f: file

-h: symbolic link

-r: readable file

-w: writable file

-x: executable file

-s: file size greater than zero

Answer 8

You can use test -d (see man test ).

-d file True if file exists and is a directory.

For example:

test -d "/etc" && echo Exists || echo Does not exist

Note: The test command is same as conditional expression [ (see: man [ ), so it's portable across shell scripts.

[ - This is a synonym for the test builtin, but the last argument must, be a literal ] , to match the opening [ .

For possible options or further help, check:

• help [
• help test
• man test or man [

Answer 9

if [ -d "$DIRECTORY" ]; then  
    # Here if $DIRECTORY exists  
fi

Answer 10

或者对于完全没用的东西：

[ -d . ] || echo "No"

Answer 11

Here's a very pragmatic idiom:

(cd $dir) || return # Is this a directory,
                    # and do we have access?

I typically wrap it in a function:

can_use_as_dir() {
    (cd ${1:?pathname expected}) || return
}

Or:

assert_dir_access() {
    (cd ${1:?pathname expected}) || exit
}

The nice thing about this approach is that I do not have to think of a good error message.

cd will give me a standard one line message to standard error already. It will also give more information than I will be able to provide. By performing the cd inside a subshell ( ... ) , the command does not affect the current directory of the caller. If the directory exists, this subshell and the function are just a no-op.

Next is the argument that we pass to cd : ${1:?pathname expected} . This is a more elaborate form of parameter substitution which is explained in more detail below.

Tl;dr: If the string passed into this function is empty, we again exit from the subshell ( ... ) and return from the function with the given error message.

---

Quoting from the ksh93 man page:

${parameter:?word}

If parameter is set and is non-null then substitute its value; otherwise, print word and exit from the shell (if not interactive). If word is omitted then a standard message is printed.

and

If the colon : is omitted from the above expressions, then the shell only checks whether parameter is set or not.

The phrasing here is peculiar to the shell documentation, as word may refer to any reasonable string, including whitespace.

In this particular case, I know that the standard error message 1: parameter not set is not sufficient, so I zoom in on the type of value that we expect here - the pathname of a directory.

A philosophical note:

The shell is not an object oriented language, so the message says pathname , not directory . At this level, I'd rather keep it simple - the arguments to a function are just strings.

Answer 12

if [ -d "$Directory" -a -w "$Directory" ]
then
    #Statements
fi

The above code checks if the directory exists and if it is writable.

Answer 13

DIRECTORY=/tmp

if [ -d "$DIRECTORY" ]; then
    echo "Exists"
fi

Try online

Answer 14

More features using find

• Check existence of the folder within sub-directories:

   found=`find -type d -name "myDirectory"` if [ -n "$found" ] then # The variable 'found' contains the full path where "myDirectory" is. # It may contain several lines if there are several folders named "myDirectory". fi

• Check existence of one or several folders based on a pattern within the current directory:

   found=`find -maxdepth 1 -type d -name "my*"` if [ -n "$found" ] then # The variable 'found' contains the full path where folders "my*" have been found. fi

• Both combinations. In the following example, it checks the existence of the folder in the current directory:

   found=`find -maxdepth 1 -type d -name "myDirectory"` if [ -n "$found" ] then # The variable 'found' is not empty => "myDirectory"` exists. fi

Answer 15

在Bash shell脚本中，可以使用什么命令来检查目录是否存在？

Answer 16

Actually, you should use several tools to get a bulletproof approach:

DIR_PATH=`readlink -f "${the_stuff_you_test}"` # Get rid of symlinks and get abs path
if [[ -d "${DIR_PATH}" ]] ; Then # Now you're testing
    echo "It's a dir";
fi

There isn't any need to worry about spaces and special characters as long as you use "${}" .

Note that [[]] is not as portable as [] , but since most people work with modern versions of Bash (since after all, most people don't even work with command line :-p), the benefit is greater than the trouble.

Answer 17

Have you considered just doing whatever you want to do in the if rather than looking before you leap?

Ie, if you want to check for the existence of a directory before you enter it, try just doing this:

if pushd /path/you/want/to/enter; then
    # Commands you want to run in this directory
    popd
fi

If the path you give to pushd exists, you'll enter it and it'll exit with 0 , which means the then portion of the statement will execute. If it doesn't exist, nothing will happen (other than some output saying the directory doesn't exist, which is probably a helpful side-effect anyways for debugging).

It seems better than this, which requires repeating yourself:

if [ -d /path/you/want/to/enter ]; then
    pushd /path/you/want/to/enter
    # Commands you want to run in this directory
    popd
fi

The same thing works with cd , mv , rm , etc... if you try them on files that don't exist, they'll exit with an error and print a message saying it doesn't exist, and your then block will be skipped. If you try them on files that do exist, the command will execute and exit with a status of 0 , allowing your then block to execute.

Answer 18

[[ -d "$DIR" && ! -L "$DIR" ]] && echo "It's a directory and not a symbolic link"

NB: Quoting variables is a good practice.

Explanation:

• -d : check if it's a directory
• -L : check if it's a symbolic link

Answer 19

To check more than one directory use this code:

if [ -d "$DIRECTORY1" ] && [ -d "$DIRECTORY2" ] then
    # Things to do
fi

Answer 20

检查目录是否存在，否则创建一个：

[ -d "$DIRECTORY" ] || mkdir $DIRECTORY

Answer 21

[ -d ~/Desktop/TEMPORAL/ ] && echo "DIRECTORY EXISTS" || echo "DIRECTORY DOES NOT EXIST"

Answer 22

Using the -e check will check for files and this includes directories.

if [ -e ${FILE_PATH_AND_NAME} ]
then
    echo "The file or directory exists."
fi

Answer 23

This answer wrapped up as a shell script

Examples

$ is_dir ~                           
YES

$ is_dir /tmp                        
YES

$ is_dir ~/bin                       
YES

$ mkdir '/tmp/test me'

$ is_dir '/tmp/test me'
YES

$ is_dir /asdf/asdf                  
NO

# Example of calling it in another script
DIR=~/mydata
if [ $(is_dir $DIR) == "NO" ]
then
  echo "Folder doesnt exist: $DIR";
  exit;
fi

is_dir

function show_help()
{
  IT=$(CAT <<EOF

  usage: DIR
  output: YES or NO, depending on whether or not the directory exists.

  )
  echo "$IT"
  exit
}

if [ "$1" == "help" ]
then
  show_help
fi
if [ -z "$1" ]
then
  show_help
fi

DIR=$1
if [ -d $DIR ]; then 
   echo "YES";
   exit;
fi
echo "NO";

Answer 24

As per Jonathan 's comment:

If you want to create the directory and it does not exist yet, then the simplest technique is to use mkdir -p which creates the directory — and any missing directories up the path — and does not fail if the directory already exists, so you can do it all at once with:

mkdir -p /some/directory/you/want/to/exist || exit 1

Answer 25

if [ -d "$DIRECTORY" ]; then
    # Will enter here if $DIRECTORY exists
fi

This is not completely true...

If you want to go to that directory, you also need to have the execute rights on the directory. Maybe you need to have write rights as well.

Therefore:

if [ -d "$DIRECTORY" ] && [ -x "$DIRECTORY" ] ; then
    # ... to go to that directory (even if DIRECTORY is a link)
    cd $DIRECTORY
    pwd
fi

---

if [ -d "$DIRECTORY" ] && [ -w "$DIRECTORY" ] ; then
    # ... to go to that directory and write something there (even if DIRECTORY is a link)
    cd $DIRECTORY
    touch foobar
fi

Answer 26

In kind of a ternary form,

[ -d "$directory" ] && echo "exist" || echo "not exist"

And with test :

test -d "$directory" && echo "exist" || echo "not exist"

Answer 27

The ls command in conjunction with -l (long listing) option returns attributes information about files and directories.
In particular the first character of ls -l output it is usually a d or a - (dash). In case of a d the one listed is a directory for sure.

The following command in just one line will tell you if the given ISDIR variable contains a path to a directory or not:

[[ $(ls -ld "$ISDIR" | cut -c1) == 'd' ]] &&
    echo "YES, $ISDIR is a directory." || 
    echo "Sorry, $ISDIR is not a directory"

Practical usage:

    [claudio@nowhere ~]$ ISDIR="$HOME/Music" 
    [claudio@nowhere ~]$ ls -ld "$ISDIR"
    drwxr-xr-x. 2 claudio claudio 4096 Aug 23 00:02 /home/claudio/Music
    [claudio@nowhere ~]$ [[ $(ls -ld "$ISDIR" | cut -c1) == 'd' ]] && 
        echo "YES, $ISDIR is a directory." ||
        echo "Sorry, $ISDIR is not a directory"
    YES, /home/claudio/Music is a directory.

    [claudio@nowhere ~]$ touch "empty file.txt"
    [claudio@nowhere ~]$ ISDIR="$HOME/empty file.txt" 
    [claudio@nowhere ~]$ [[ $(ls -ld "$ISDIR" | cut -c1) == 'd' ]] && 
        echo "YES, $ISDIR is a directory." || 
        echo "Sorry, $ISDIR is not a directoy"
    Sorry, /home/claudio/empty file.txt is not a directory

Answer 28

file="foo" 
if [[ -e "$file" ]]; then echo "File Exists"; fi;

Answer 29

可以使用以下find ，

find . -type d -name dirname -prune -print

Answer 30

There are great solutions out there, but ultimately every script will fail if you're not in the right directory. So code like this:

if [ -d "$LINK_OR_DIR" ]; then
if [ -L "$LINK_OR_DIR" ]; then
    # It is a symlink!
    # Symbolic link specific commands go here
    rm "$LINK_OR_DIR"
else
    # It's a directory!
    # Directory command goes here
    rmdir "$LINK_OR_DIR"
fi
fi

will execute successfully only if at the moment of execution you're in a directory that has a subdirectory that you happen to check for.

I understand the initial question like this: to verify if a directory exists irrespective of the user's position in the file system. So using the command 'find' might do the trick:

dir=" "
echo "Input directory name to search for:"
read dir
find $HOME -name $dir -type d

This solution is good because it allows the use of wildcards, a useful feature when searching for files/directories. The only problem is that, if the searched directory doesn't exist, the 'find' command will print nothing to standard output (not an elegant solution for my taste) and will have nonetheless a zero exit. Maybe someone could improve on this.

Answer 31

(1)

[ -d Piyush_Drv1 ] && echo ""Exists"" || echo "Not Exists"

(2)

[ `find . -type d -name Piyush_Drv1 -print | wc -l` -eq 1 ] && echo Exists || echo "Not Exists"

(3)

[[ -d run_dir  && ! -L run_dir ]] && echo Exists || echo "Not Exists"

If an issue is found with one of the approaches provided above:

With the ls command; the cases when a directory does not exists - an error message is shown

[[ `ls -ld SAMPLE_DIR| grep ^d | wc -l` -eq 1 ]] && echo exists || not exists

-ksh: not: not found [No such file or directory]

Answer 32

Use the file program. Considering all directories are also files in Linux, issuing the following command would suffice:

file $directory_name

Checking a nonexistent file: file blah

Output: cannot open 'blah' (No such file or directory)

Checking an existing directory: file bluh

Output: bluh: directory

Answer 33

一个班轮：

[[ -d $Directory ]] && echo true

Answer 34

If you want to check if a directory exists, regardless if it's a real directory or a symlink, use this:

ls $DIR
if [ $? != 0 ]; then
        echo "Directory $DIR already exists!"
        exit 1;
fi
echo "Directory $DIR does not exist..."

Explanation: The "ls" command gives an error "ls: /x: No such file or directory" if the directory or symlink does not exist, and also sets the return code, which you can retrieve via "$?", to non-null (normally "1"). Be sure that you check the return code directly after calling "ls".

Answer 35

From script file myScript.sh :

if [ -d /home/ec2-user/apache-tomcat-8.5.5/webapps/Gene\ Directory ]; then
   echo "Directory exists!"
   echo "Great"
fi

Or

if [ -d '/home/ec2-user/apache-tomcat-8.5.5/webapps/Gene Directory' ]; then
   echo "Directory exists!"
   echo "Great"
fi

Answer 36

Git Bash + Dropbox + Windows:

None of the other solutions worked for my Dropbox folder, which was weird because I can Git push to a Dropbox symbolic path.

#!/bin/bash

dbox="~/Dropbox/"
result=0
prv=$(pwd) && eval "cd $dbox" && result=1 && cd "$prv"
echo $result

read -p "Press Enter To Continue:"

You'll probably want to know how to successfully navigate to Dropbox from Bash as well. So here is the script in its entirety.

https://pastebin.com/QF2Exmpn

Answer 37

Just as an alternative to the '[ -d ]' and '[ -h ]' options, you can make use of stat to obtain the file type and parse it.

#! /bin/bash
MY_DIR=$1
NODE_TYPE=$(stat -c '%F' ${MY_DIR} 2>/dev/null)
case "${NODE_TYPE}" in
        "directory") echo $MY_DIR;;
    "symbolic link") echo $(readlink $MY_DIR);;
                 "") echo "$MY_DIR does not exist";;
                  *) echo "$NODE_TYPE is unsupported";;
esac
exit 0

Test data:

$ mkdir tmp
$ ln -s tmp derp
$ touch a.txt
$ ./dir.sh tmp
tmp
$ ./dir.sh derp
tmp
$ ./dir.sh a.txt
regular file is unsupported
$ ./dir.sh god
god does not exist

Answer 38

I collected below a few less-known options to check directory existence, also the well-known ones were included (some of them might be already covered in the previous answers).

All examples were tested on Ubuntu 18.04 , so they might not always work on some other type of OS'es (most of them should work smoothly in most Linux distributions or on Mac OS though). The directory path can be changed to any directoy, in the examples below /tmp was used.

1. Using the test command:

if test -d /tmp; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

2. Using the [ -d ] test operator:

if [ -d /tmp ]; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

3. Using the [[ -d ]] test operator (This is similar to the previous one, but more powerful):

if [[ -d /tmp ]]; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

4. Using the -e test operator (This checks if file exist, it works for both file and directory):

if [ -e /tmp ]; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

5. Using the ls command and redirecting the output to /dev/null :

if ls -d /tmp > /dev/null 2>&1; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

6. Using find command:

if find /tmp -mindepth 1 -print -quit 2>/dev/null; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

7. Using stat command:

if stat /tmp > /dev/null 2>&1; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

8. Using dirname command:

if [ "$(dirname /tmp)" != "/tmp" ]; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

9. Using readlink command:

if readlink -e /tmp > /dev/null 2>&1; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

10. Using realpath command:

if realpath /tmp > /dev/null 2>&1; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

11. Using cd command:

if cd /tmp; then
  echo "Directory exists"
  cd - >/dev/null
else
  echo "Directory does not exist"
fi

12. Using grep command:

if ls -d /tmp 2>/dev/null | grep -q '/tmp'; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi

13. Using Python os module:

if python -c "import os; print(os.path.isdir('/tmp'))" | grep -q "True"; then
  echo "Directory exists"
else
  echo "Directory does not exist"
fi