Linux/UNIX: Find Out If File Exists With Conditional Expressions

by nixCraft on February 16, 2006 · 25 comments· LAST UPDATED November 16, 2008

With the help of BASH shell and IF command it is possible to find out if file exists or not. Generally, this is known as conditional expressions. Conditional expressions are used by the [[ compound command and the test and [ builtin commands to test file attributes and perform string and arithmetic comparisons. General syntax:

[ parameter FILE ]
OR
test parameter FILE

Where parameter can be any one of the following:

-e: Returns true value if file exists
-f: Return true value if file exists and regular file
-r: Return true value if file exists and is readable
-w: Return true value if file exists and is writable
-x: Return true value if file exists and is executable
-d: Return true value if exists and is a directory

Examples

Find out if file /etc/passwd file exists or not

Type the following commands:
$ [ -f /etc/passwd ] && echo "File exists" || echo "File does not exists" $ [ -f /tmp/fileonetwo ] && echo "File exists" || echo "File does not exists"

Find out if directory /var/logs exists or not

Type the following commands:
$ [ -d /var/logs ] && echo "Directory exists" || echo "Directory does not exists" $ [ -d /dumper/fack ] && echo "Directory exists" || echo "Directory does not exists"
You can use conditional expressions in a shell script:

#!/bin/bash
FILE=$1
 
if [ -f $FILE ];
then
   echo "File $FILE exists"
else
   echo "File $FILE does not exists"
fi

Save and execute the script:
$ chmod +x script.sh $ ./script.sh /path/to/file $ ./script.sh /etc/resolv.conf

You can use this technique to verify that backup directory and backup source directory exits See example script for more information.

If you would like to be kept up to date with our posts, you can follow us on Twitter, Facebook, Google+, or even by subscribing to our RSS Feed.

Featured Articles:

{ 25 comments… read them below or add one }

1 loony October 27, 2007 at 2:17 pm

For me the if statement only works when using the FILE var with quotes like this:

if [ -f "$FILE" ];

2 aditya May 12, 2008 at 5:21 am

script was very userful

3 Mehdi Anis December 3, 2008 at 4:49 pm

I need to check a file on daily basis that is created by anotehr process. The file format is:

DataFile_MMDDYYYY.csv

So, I need to get today’s date in MMDDYYYY format, concate that with a string variable, FileName = “DataFile_” + DatePart + “.csv”

Then look for that FileName file if exists then run a command (sas sendemail.sas).

How can I achieve that? Thanks.

4 thant December 8, 2008 at 4:57 pm

DatePart=`date ‘+%m%d%Y`
FileName =DataFile_${DatePart}.csv

5 Don Petrus January 14, 2009 at 3:03 pm

Hello Volks:
I would like to look for a File: if it exists – AND – it´smaller (lt/gt) than 1000000, then … echo ” File too small” , return 1 … and so on:

#!/bin/bash
FILE=nec2.txt
if -f [ "$FILE" ] && -f [ "$FILE" -lt 1000000 ] ;
then
echo “File $FILE too small”
else
echo “File $FILE does not exists”
fi

-rw-rw—- 1 cas lokus 31626 2008-12-15 14:00 xnec2.txt

I use linux 2.4.21-278-smp

Can you please help there ? Pleas reply to donpetrus@hotmail.com
Many thanks in advance – Petrus

6 Bram April 6, 2009 at 9:02 am

Bash knows the NOT procedure for IF. So No ELSE would be used. watch the !

#!/bin/bash
FILE=$1
if [ ! -f $FILE ];
then
   echo "File $FILE does not exists"
fi

7 Zach October 1, 2009 at 8:52 pm

I just hacked this together. I plan to use it for my other scripts. The exit statements make the script exit with a 0 (bash standard for successful completion) or a 1 (non-zero is the bash standard for a failed action)

#!/bin/bash
FILE=$1
if [ -f $FILE ];
then
exit 0
else
exit 1
fi

8 Satyajit Sahoo September 20, 2012 at 9:10 am: Just this much will do,
#!/bin/bash
FILE=$1
[[ -f $FILE ]]
Reply

9 Rajee October 9, 2009 at 10:06 am

How to check some set of files in the following directory and do the process.
my statement following is not working: pls explain
if [ -f "$ROOT/abc/files/CUST*" ]; then
echo “inside customer file exists”
else
echo “No customer file exists”
fi
CUST is the post fix of the files, expected to have more than 1 file on some days.

10 Fred November 17, 2009 at 1:31 pm

For me, it only works without variables, like

if [ -f /home/user/hey.jpg ]; then
….
else
….
fi

Worth trying.

11 Debbie November 24, 2009 at 7:41 pm

I want to test if any file ending in *.DATGO exists.
Do you always have to use the exact name of the file?

12 krishna January 24, 2010 at 1:21 pm

I need the shell script to check whether the file exist or not
and whether the format of the file is .dat or not

expecting the help ASAP…pls

13 amit March 11, 2010 at 5:09 pm

the only thing i can say is that -

if statement does’nt allow wild card, you have to think a work around for this

14 Anthony Youngman May 28, 2010 at 8:40 pm

ls D
blah blah blah
drwx—— Program Files

if -d D/Program\ Files returns FALSE

It would be nice if I could find some way of successfully testing for names with spaces :-(

Cheers,
Wol

15 Sergani August 2, 2011 at 1:26 am: Try ls -1D (that’s ls -’ONE’ -D)
Reply

16 Jasper August 2, 2010 at 10:57 am

Hi,

I need to check if a file with the current date exists in a folder. How would I do that?

17 Betulino August 12, 2010 at 8:06 am

Hi,

I have /media/USBDisk0 and that the mount point for my USBDisk.
And a hard link named /media/TheData/Data -> /media/USBDisk0/Data
When the USB is mounted, the hard link is OK, but If something fail, the hard link is broken…. Can use the if to test the hard link?

18 sonal February 7, 2011 at 6:34 am

i need to check all the files in the current directory and display them.how can i do this?

19 Sergani August 2, 2011 at 1:30 am: cd /path/to/directory
for i in $(ls -1 *)
do
if [ -f $i ] ; then
ll $i
else
echo “$i is not a file”
fi
Reply

20 Lalit Mohan March 7, 2011 at 6:35 am

I want to check file that i fetching is complete or not, if file is still copying than wait for few minutes, can this things possible, Reply me Please!!!

21 Ked June 28, 2011 at 1:05 pm

That was a great help, I needed a script to check if the .parentlock file was present in the Thunderbird profile directory and then delete it if it was.

Worked first time :)

22 Sergani August 2, 2011 at 1:32 am: you could also have done the following:
find /home/username/thunderbird-directory/ -iname .parentlock -ok rm {} ;\
it’ll find the file and attempt to remove it, but will ask you first… if you need it to remove it right away, replace -ok with -exec
Reply

23 Ravi Theja September 13, 2011 at 8:05 pm

if [ -e filename ] works for me and checks fine ONLY when I’m logged in as a power broker. It doesn’t test when I log in as a normal user or call the script from a different scheduling tool.

Please help me ASAP

24 chey December 2, 2011 at 3:41 pm

Thanks for the script, it was very useful.

25 Rahul May 14, 2012 at 7:20 pm

i need shell script where the i need to connect from one server to another server…
and check for file *.mediate.log in path /home/apps/ and if found it need to execute a script prescript.sh in the same path and return a status to the server…and if the files doesn’t exist it shud return another status…and if the job fails becoz of any resin it need to return another status…
Can you please help me with this ASAP…very urgent