Linux check if directory or file

Check if a directory exists in Linux or Unix shell

How to check if a directory exists in Linux

1. One can check if a directory exists in a Linux shell script using the following syntax:
   [ -d «/path/dir/» ] && echo «Directory /path/dir/ exists.»
2. You can use ! to check if a directory does not exists on Unix:
   [ ! -d «/dir1/» ] && echo «Directory /dir1/ DOES NOT exists.»

One can check if a directory exists in Linux script as follows:

Always enclose “$DIR” in double-quotes to deal with directories having white/black spaces in their names. For instance:

A note about symbolic links (symlink)

Directories with symbolic links need special consideration as follows using the -L switch:

Linux check if a directory exists and take some action

Here is a sample shell script to see if a folder exists or not in Linux:

Run it as follows:
./test.sh
./test.sh /tmp/
./test.sh /nixCraft

Check if directory exists in bash and if not create it

Here is a sample shell script to check if a directory doesn’t exist and create it as per our needs:

Make sure you always wrap shell variables such as $DIR in double quotes ( «$DIR» to avoid any surprises in your shell scripts:

Using test command

One can use the test command to check file types and compare values. For example, see if FILE exists and is a directory. The syntax is:
test -d «DIRECTORY» && echo «Found/Exists» || echo «Does not exist»
The test command is same as [ conditional expression. Hence, you can use the following syntax too:
[ -d «DIR» ] && echo «yes» || echo «noop»

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Getting help

Read bash shell man page by typing the following man command or visit online here:
man bash
help [
help [[
man test

Conclusion

This page explained various commands that can be used to check if a directory exists or not, within a shell script running on Linux or Unix-like systems. The -d DIR1 option returns true if DIR1 exists and is a directory. Similarly, the -L DIR1 option returns true if DIR1 found and is a symbolic links.

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How to check directory exist or not in linux.? [duplicate]

Given a file path (e.g. /src/com/mot ), how can I check whether mot exists, and create it if it doesn’t using Linux or shell scripting??

6 Answers 6

With bash/sh/ksh, you can do:

For files, replace -d with -f , then you can do whatever operations you need on the non-existant file.

mkdir -p creates the directory without giving an error if it already exists.

Check for directory exists

Check for directory does not exist

Well, if you only check for the directory to create it if it does not exist, you might as well just use:

mkdir -p will create the directory if it does not exist, otherwise does nothing.

This is baisc, but I think it works. You’ll have to set a few variables if you’re looking to have a dynamic list to cycle through and check.

Hope that’s what you were looking for.

Not the answer you’re looking for? Browse other questions tagged linux shell or ask your own question.

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How to check if a directory exists in Linux command line?

How to check if a directory exists in Linux command line?

Solution: [ -d ¨a¨ ]&&echo ¨exists¨||echo ¨not exists¨

7 Answers 7

Assuming your shell is BASH:

The canonical way is to use the test(1) utility:

where path is the pathname of the directory you want to check for.

For example:

[ -d «YOUR_DIR» ] && echo «is a dir»

[ -d / ] && echo «root dir «

will output: root dir .

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

to check the opposite , add ! before the -d ->[ ! -d . ]

I usually just ls it:

If it exists, you’ll see its contents, if it doesn’t exist you’ll see an error like this:

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C++ — Determining if directory (not a file) exists in Linux [duplicate]

How would I determine if a directory (not a file) existed using C++ in Linux? I tried using the stat() function but it returned positive when a file was found. I only want to find if the inputted string is a directory, not something else.

6 Answers 6

According to man(2) stat you can use the S_ISDIR macro on the st_mode field:

Side note, I would recommend using Boost and/or Qt4 to make cross-platform support easier if your software can be viable on other OSs.

how about something i found here

If you can check out the boost filesystem library. It’s a great way to deal with this kind of problems in a generic and portable manner.

In this case it would suffice to use:

The way I understand your question is this: you have a path, say, /foo/bar/baz (baz is a file) and you want to know whether /foo/bar exists. If so, the solution looks something like this (untested):

In C++17**, std::filesystem provides two variants to determine the existence of a path:

1. is_directory() determines, if a path is a directory and does exist in the actual filesystem
2. exists() just determines, if the path exists in the actual filesystem (not checking, if it is a directory)

Example (without error handling):

Both functions throw filesystem_error in case of errors. If you want to avoid catching exceptions, use the overloaded variants with std::error_code as second parameter.

If you want to find out whether a directory exists because you want to do something with it if it does (create a file/directory inside, scan its contents, etc) you should just go ahead and do whatever you want to do, then check whether it failed, and if so, report strerror(errno) to the user. This is a general principle of programming under Unix: don’t try to figure out whether the thing you want to do will work. Attempt it, then see if it failed.

If you want to behave specially if whatever-it-was failed because a directory didn’t exist (for instance, if you want to create a file and all necessary containing directories) you check for errno == ENOENT after open fails.

I see that one responder has recommended the use of boost::filesystem . I would like to endorse this recommendation, but sadly I cannot, because boost::filesystem is not header-only, and all of Boost’s non-header-only modules have a horrible track record of causing mysterious breakage if you upgrade the shared library without recompiling the app, or even if you just didn’t manage to compile your app with exactly the same flags used to compile the shared library. The maintenance grief is just not worth it.

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Bash Shell Check Whether a Directory is Empty or Not

H ow do I check whether a directory is empty or not under Linux / UNIX using a shell script? I would like to take some action if directory is empty on a Linux or Unix like system. How can I check from bash/ksh shell script if a directory contains files? How do I check whether a directory is empty or not?

There are many ways to find out if a directory is empty or not under Linux and Unix bash shell. You can use the find command to list only files.

Tutorial details
Difficulty level	Easy
Root privileges	No
Requirements	None
Est. reading time	3 mintues

In this example, find command will only print file name from /tmp. If there is no output, directory is empty.

Check whether a directory is empty or not using find command

The basic syntax is as follows:

The -empty test if given file is empty and is either a regular file or a directory. For example:
$ mkdir /tmp/demo
$ find /tmp/demo -maxdepth 0 -empty -exec echo <> is empty. \;
/tmp/demo is empty.
$ touch /tmp/demo/file.txt
$ ls -l /tmp/demo/file.txt
$ find /tmp/demo -maxdepth 0 -empty -exec echo <> is empty. \;
In this example, check whether a directory called /tmp/ is empty or not, type:
$ find «/tmp» -type f -exec echo Found file <> \;
Sample outputs:

However, the simplest and most effective way is to use ls command with -A option:
$ [ «$(ls -A /path/to/directory)» ] && echo «Not Empty» || echo «Empty»
or
$ [ «$(ls -A /tmp)» ] && echo «Not Empty» || echo «Empty»
You can use if..else.fi in a shell script:

Run it as follows:
./script /tmp
./script /tmp/foobar
mkdir /tmp/foobar
./script /tmp/foobar
touch /tmp/foobar/filename
./script /tmp/foobar

Bash scripting – Test for empty directory and files

Here is another example using bash for loop to check for any *.c files in the

Check if folder /data/ is empty or not using bash only features

From the Linux and Unix bash(1) man page:

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• nullglob If set, bash allows patterns which match no files to expand to a null string, rather than themselves.
• dotglob – If set, bash includes filenames beginning with a . in the results of pathname expansion.

A note about ksh user

Try for loop as follows:

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Comments on this entry are closed.

Seems to me that using ls is not required – in fact, it is doable within the shell alone:

set — `echo .* *`
if [ $# = «2» ] ; then
: empty directory
else
: not empty .
fi

It is not working for me. I’m using Debian + Bash 3. It returns 3 when directory is empty, it should be 2 as empty directory has only . and ..

Yes. I’d forgotten: when no matches are found (“*”) then the resulting text is the character unchanged. This should work better:

FILES=”`echo .* *`”
if [ $FILES = ‘. .. *’ ] ; then
: empty dir
else
: not empty
fi

find -type d -empty

`find . -depth -type d -empty` would work a little better..
EG:

Scot’s suggestion works absolutely perfectly.

A slight variation on the original post which does it numerically and includes dot files.

That’s a one and not an ‘l’ to the ls command. An empty directory only has the two entries – . & ..

Works with both BSD and GNU Linux find:
find «/nas/data» -maxdepth 0 -empty -exec echo <> is empty. \;
OR
find «/dir2» type d -empty -exec command1 -arg1 <> \;

I am trying to pass a directory path as a parameter to my bash script (which tests whether its empty), but the directory name contains spaces. Any suggestions?

enclose the directory name parameter in double quotes.

The following code does not correctly identify empty directories. Using DIR=$1 then passing “home/dan/not empty” does not help, neither does using “home/dan/not\ empty” or home/dan/not\ empty.

DIR=”home/dan/not empty”
if [ “$(ls -A $DIR)” ]; then
echo “$DIR is not empty”
else
echo “$DIR is empty”
fi

if [ “$(ls -A $DIR)” ]; then

if [ “$(ls -A “$DIR”)” ]; then

That’s just another pair of quotes, no escapes. Should work.

dude. give find some love 😉

find . -type d -empty -exec touch <>/.empty \;

find «/dir2» -type d -empty -exec command1 -arg1 <> \;

if [ «$(ls -A $DIR)» ]; then
How can I use this expression exclude one directory?

what if the directory has files but each file is of 0 size?

best way is to do as below:

This snippet assumes that a directory size, by its own name, is always 4096 bytes, approximated to 4.0K evaluated to int as 4

Hi all,
someone please say me why this dont work.

Declare the variable ,before you use it.

Ok, this works, after hours of coding a simple solution was found to be best loll.What kept giving me trouble was the *, also I had found a solution a long time ago, but it didnt work if you had empty files in the directory.I tried all the IF statement solutions and it wont work in all situations.So best method is below:

for i in $DIR/*
do
if [ -e $i ] && [ $(echo $?) -eq “0 ” ]

then
echo The Directory is NOT EMPTY

echo The directory is EMPTY

Very good Vivek. Cool.

if [ $( stat -c %h . ) -gt 2 ] ; then echo not empty; fi
Solution with “$(ls -A $DIR)” could exceed command buffer size.

Square brackets are only needed with if when you’re using test expressions, and by doing away with them you can do away with the process substitution. You can test the exit status of a program or command just by running it. (Getting ls to give an error code in this case requires a slight change in syntax.)

If used in a script, I’d go with a slight modification of the first comment (as the “set” clobbers positional parameters, putting it in a function will clobber only local function parameters, not the global ones!):

And then calling:

why not using simple :

if [ ! -f /folder/* ]; then
echo “folder not empty”
else
echo “folder empty”
fi

I had a seriously nasty time with this.

In a bash script I wanted to:
1. Create and pass a list of directories that match a pattern
2. Use a variable to check if the directories matching the pattern were empty
3. Delete empty directories.

The challenge I ran into was with wildcard expansion in variables. I spent a little while pulling my hair out over ” and ‘ and ` until I figured out (the final solution was pretty simple).

Here is my short script that
1. creates a list of directories within $1 that match a pattern
– in this case the grep returns all directories that are 5 numerical digits
2. verifies whether or not content exists
3. deletes the directory if no content is present

#!/bin/bash
# List Empty Directories that are directories in the
# format ./##### If they are empty, delete them.

ls -d */ > testdir.txt
grep ‘9\<5\>’ ./testdir.txt > testdir2.txt
rm ./testdir.txt

while [ $i -le `wc -l ./testdir2.txt | gawk ‘’` ]; do
line=`head -$i ./testdir2.txt | tail -1`
correctdirname=”./”$line
echo -n “Dir “$i” “$correctdirname

files=`echo $correctdirname $correctdirname*`
test=$correctdirname” “$correctdirname”*”
if [ “$files” == “$test” ]
then echo ” empty” #; rm -rf $correctdirname
else echo ” files found”
fi

For safety I commented out the delete/rm. Anyone trying this should test carefully before running this script and use a test directory with test data. The delete command will delete entire directories whether they are empty or not! Verify your scenario, verify the variables match your scenario, and double-check before uncommenting that rm command.

I hope someone finds this useful.

I mistakenly said “1. creates a list of directories within $1 that match a pattern”
It should read “1. creates a list of directories within the current directory that match a pattern”

Also I didn’t remove testdir2.txt, created by the script in the current directory. A line to remove that could be added after the “done” to clean up the 2nd temporary file created by the script.

After having solved the logic problem I was overly-focused on I was playing around with additional information from the above posts and changed my if statment based upon the one provided by nixcraft, above:
My if original: if [ “$files” == “$test” ]
Nixcraft’s if: if [ “$(ls -A $DIR)” ]
My new if: if [ ! “$(ls -A $line)” ]

Using the if provided by Nixcraft I came up with an if that works in place of the if statement in my above script and is a little cleaner because it does not require creation of the $test variable. I put a ! in front of it so I could easily swap if statements. Alternately you could reverse the then-else.

Here is the updated script with the old vars and if commented out:

#!/bin/bash
# List Empty Directories that are directories in the
# format ./##### If they are empty, delete them.

ls -d */ > testdir.txt
grep ‘6\<5\>’ ./testdir.txt > testdir2.txt
rm ./testdir.txt

while [ $i -le `wc -l ./testdir2.txt | gawk ‘’` ]; do
line=`head -$i ./testdir2.txt | tail -1`
correctdirname=”./”$line
echo -n “Dir “$i” “$correctdirname

# files=`echo $correctdirname $correctdirname*`
# test=$correctdirname” “$correctdirname”*”
# if [ “$files” == “$test” ]
if [ ! “$(ls -A $line)” ]
then echo ” empty” #; rm -rf $correctdirname
else echo ” files found”
fi

Note I added the final line to remove the 2nd test/data file.

Also you should be able to comment out the if and uncomment the 3 lines above it to switch back and forth between the two options.

This is why I don’t post often. I keep finding mistakes. I don’t know how other posters do it–such simple elegant posts that are correct.

Upon further inspection I realized my if statement, while it works in my bash, is using the wrong variable. I created the $correctdirname variable because grepping directories gave me ##### rather than ./#####.
if [ ! “$(ls -A $line)” ]

I believe you should be using $correctdirname for the reason above even though the script works for me–I don’t know if it will work generically given the difference.

The “more-correct” if-statement:
if [ ! “$(ls -A $correctdirname)” ]

if [ ! “$(ls -A “$FOLDER”)” ]; then
echo “$FOLDER is empty”
fi

When searching for methods to automatically mount virtualbox shared folders,
reliable and correct methods are hard to distinguish from those that fail.
Failures include getting and setting permissions, as well as other problems.

Methods that fail include:
modifying /etc/fstab
modifying /etc/rc.local

I am fairly certain that rc.local can be used,
but no methods I have tried worked.
I welcome improvements on these guidelines.

On virtualbox 4.2.14 running nautilus (bash terminal) on an ubuntu 13.04 guest,
Below is a working method to mount Common (sharename)
on /home/$USER/Desktop/Common (mountpoint) with full permissions.
(Note the ‘\’ command continuation character in the find command.)

First time only: create your mountpoint, modify your .bashrc file, and run it.
Respond with password when requested.
These are the four command-lines needed.

mkdir $HOME/Desktop/Common
sudo echo “$USER ALL=(ALL) NOPASSWD:ALL” >> /etc/sudoers
find $HOME/Desktop/Common -maxdepth 0 -type d -empty -exec sudo \
mount -t vboxsf -o \
uid=`id -u $USER`,gid=`id -g $USER` Common $HOME/Desktop/Common \;
source

/.bashrc # Needed if you want to mount Common in this bash.

All other times: simply launch a bash shell.

The find command detects an empty mountpoint directory.
If the Common directory is not empty, it does not run the mount command.

I hope this is error-free and sufficiently general.
Please let me know of corrections and improvements.

How to make two directories “C_ Programming ” and “Shell Script” ?

A)Create a text file “Pros_and_Cons_of_C.txt” in “C_programming” directory
B)Create a text file “Pros_and_Cons_of_C.txt” in “Shell_Script” directory
C)Write a suitable pros and cons for each text file in your own words using keyboards inputs.

Write a shell script to create a directory “Shell2” Create 10 text files “a5_1.txt” “a5_10.txt” using loop inside the directory “Shell2.” Give access privilege for those text files , read only for others and group , read and write for owner..

Please help me for above all forums that i sent. those are may be primary level questions , but i can’t understand for answer those questions. please help me for do my university assignment..

That’s great for you, learning Linux computer science, and this means first: learn. Nobody can do it for you.
Fortunately, somebody has built and offered to all a great resource to learn, which is also a cooperative work:
http://bash.cyberciti.biz/guide/Main_Page

I could have added, among other resources:

Not a better solution, but this also works:

Please remove/disregard my previous comment, this is what I meant. Checks for just one folder (current one) and it’s size being 4096 bytes.

rm -rf “%*”
mkdir “%*”
echo NOW it’s empty.
exit 0

Thanks for this post! I have a comment and a potential method.

Method: Why wouldn’t this work?
ls $DIR/*
echo $? # a ‘1’ would mean the directory is empty

Comment: As far as I can tell, this version, the find command version, and ls -A, will not detect a directory that contains subdirectories but is void of files. I am perplexed that the below does not work. Assume $DIR has a single subdirectory, foo, and neither have regular files:
find $DIR -type f -exec echo $DIR is empty \;

PS I did find for my ancillary problem (may contain subdirectories but no files) this solution:
let “$m = `find $DIR -type f | wc -l`” ; test $m = 0 ; echo $?

Also, a nit in my original suggestion: adjust the ls command so you don’t get unwanted output:
ls $DIR/* > /dev/null
echo $? # a ’1′ would mean the directory is empty

if [ “$(ls -A $DIR)” ]; then
echo “Take action $DIR is not Empty”
else
echo “$DIR is Empty”
fi

could be written a bit simpler without backquote substitution:

if ls -A $DIR >/dev/null
then
echo Take action ….
else
echo $Dir is empty
fi

NO, this is not true. Your check

checks for the EXIT value of “ls”, which is 0 if directory $DIR exists (even if it is empty),
while

[ “$(ls -A $DIR)” ] checks whether the OUTPUT of “ls” is non-empty, i.e. the directory is non-empty. See the man page test(1).

Thank you, VVS. Worked like a charm for a novice.

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