Linux if test file exists

3 ways to check if file exists in bash

In this blog post, we will discuss 3 different ways to check if a file exists in Bash. This is an important skill to have when you are working with files in a Linux environment. Each of these methods has its own benefits and drawbacks, so it is important to understand them all before deciding which one to use. Let’s get started!

The following Linux commands can be used to check if a file exists in bash.

• test -f /path/to/file && echo “FILE exists.” || echo “File does not exist”
• [ -e /path/to/file ] && echo “FILE exists.” || echo “File does not exist”
• [ -f /path/to/file ] && echo “FILE exists.” || echo “File does not exist”

Check if a File Exists Using the test Command in bash

The first method we will discuss is using the test command. This is a built-in command in Bash that can be used to test various things. In this case, we are interested in using it to check if a file exists. The syntax for this command is as follows:

If the file exists, this command will return a 0 exit code. If the file does not exist, it will return a non-zero exit code. So, we can use this command to check if a file exists like so:

if test -e /path/to/file; then
echo “File exists”
else
echo “File does not exist”
fi

We can do this in one command like this.
test -e /path/to/file && echo “FILE exists.” || echo “File does not exist”

Check if a File Exists Using if statement -e option in bash

The best Linux command to check if a file Exists in bash is using the if statement -e option. The -e option is a built-in operator in Bash to check file exists. If the file exists, this command will return a 0 exit code. If the file does not exist, it will return a non-zero exit code.

The syntax for this operator is as follows:

if [ -e /path/to/file ] ; then
echo “File exists”
else
echo “File does not exist”
fi

We can do this in one command.

[ -e /path/to/file ] && echo “FILE exists.” || echo “File does not exist”

Check if a File Exists Using -f option in bash if statement

The third method we will discuss is using the -f option in if statement. The -e option checks if the file path exists, while the -f option checks if the file path exists and if it is a regular file. The syntax for these operators are as follows:

if [-f /path/to/file ] ; then
echo “File exists”
else
echo “File does not exist”
fi

we can do this in one command line.
[ -f /path/to/file ] && echo “FILE exists.” || echo “File does not exist”

File test operators in bash

The test command includes the following FILE operators that allow you to test for particular types of files:

• -d FILE FILE exists and is a directory.
• -e FILE FILE exists.
• -r FILE FILE exists and the read permission is granted.
• -s FILE FILE exists and it’s size is greater than zero (ie. it is not empty).
• -w FILE FILE exists and the write permission is granted.
• -x FILE FILE exists and the execute permission is granted.

As you can see, there are many different ways to check if a file exists in Bash. Each of these methods has its own benefits and drawbacks, so it is important to understand them all before deciding which one to use. In general, the “test” command is the simplest and most reliable way to check if a file exists. However, the other methods can be useful in certain situations. Thanks for reading!

David is a Cloud & DevOps Enthusiast. He has years of experience as a Linux engineer. He had working experience in AMD, EMC. He likes Linux, Python, bash, and more. He is a technical blogger and a Software Engineer. He enjoys sharing his learning and contributing to open-source.

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Check If the File Exists in Bash

Different types of files are used in Bash for different purposes. Many options are available in Bash to check if the particular file exists or not. The existence of the file can be checked using the file test operators with the “test” command or without the “test” command. The purposes of different types of file test operators to check the existence of the file are shown in this tutorial.

File Test Operators

Many file test operators exist in Bash to check if a particular file exists or not. Some of them are mentioned in the following:

Operator	Purpose
-f	It is used to check if the file exists and if it is a regular file.
-d	It is used to check if the file exists as a directory.
-e	It is used to check the existence of the file only.
-h or -L	It is used to check if the file exists as a symbolic link.
-r	It is used to check if the file exists as a readable file.
-w	It is used to check if the file exists as a writable file.
-x	It is used to check if the file exists as an executable file.
-s	It is used to check if the file exists and if the file is nonzero.
-b	It is used to check if the file exists as a block special file.
-c	It is used to check if the file exists as a special character file.

Different Examples to Check Whether the File Exists or Not

Many ways of checking the existence of the regular file are shown in this part of the tutorial.

Example 1: Check the Existence of the File Using the -F Operator with Single Third Brackets ([])

Create a Bash file with the following script that takes the filename from the user and check whether the file exists in the current location or not using the -f operator in the “if” condition with the single third brackets ([]).

echo -n «Enter the filename: «

#Check whether the file exists or not using the -f operator

The script is executed twice in the following script. The non-existence filename is given in the first execution. The existing filename is given in the second execution. The “ls” command is executed to check whether the file exists or not.

Example 2: Check the Existence of the File Using the -F Operator with Double Third Brackets ([[ ]])

Create a Bash file with the following script that takes the filename as a command-line argument and check whether the file exists in the current location or not using the -f operator in the “if” condition with the double third brackets ([[ ]]).

#Take the filename from the command-line argument

#Check whether the argument is missing or not

#Check whether the file exists or not using the -f operator

if [ [ -f » $filename » ] ] ; then

The script is executed twice in the following script. No argument is given in the first execution. An existing filename is given as an argument in the second execution. The “ls” command is executed to check whether the file exists or not.

Example 3: Check the Existence of the File Using the -F Operator with the “Test” Command

Create a Bash file with the following script that takes the filename as a command-line argument and check whether the file exists in the current location or not using the -f operator with the “test” command in the “if” condition.

#Take the filename from the command-line argument

#Check whether the argument is missing or not

echo «No argument is given.»

#Check whether the file exists or not using the -f operator

if test -f » $filename » ; then

The script is executed twice in the following script. No argument is given in the first execution. An existing filename is given in the second execution.

Example 4: Check the Existence of the File with the Path

Create a Bash file with the following script that checks whether the file path exists or not using the -f operator with the “test” command in the “if” condition.

#Set the filename with the directory location

#Check whether the file exists or not using the -f operator

if test -f » $filename » ; then

The following output appears after executing the script:

Conclusion

The methods of checking whether a regular file exists or not in the current location or the particular location are shown in this tutorial using multiple examples.

About the author

Fahmida Yesmin

I am a trainer of web programming courses. I like to write article or tutorial on various IT topics. I have a YouTube channel where many types of tutorials based on Ubuntu, Windows, Word, Excel, WordPress, Magento, Laravel etc. are published: Tutorials4u Help.

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Check if file exists [BASH]

Any ideas please? I will be glad for any help. P.S. I wish I could show the entire file without the risk of being fired from school for having a duplicate. If there is a private method of communication I will happily oblige. My mistake. Fas forcing a binary file into a wrong place. Thanks for everyone’s help.

4 Answers 4

Little trick to debugging problems like this. Add these lines to the top of your script:

The set -xv will print out each line before it is executed, and then the line once the shell interpolates variables, etc. The $PS4 is the prompt used by set -xv . This will print the line number of the shell script as it executes. You’ll be able to follow what is going on and where you may have problems.

Here’s an example of a test script:

#! /bin/bash export PS4="\$LINENO: " set -xv FILE1="$" # Line 6 if [ ! -e "$FILE1" ] # Line 7 then echo "requested file doesn't exist" >&2 exit 1 else echo "Found File $FILE1" # Line 12 fi 

And here’s what I get when I run it:

$ ./test.sh .profile FILE1="$" 6: FILE1=.profile if [ ! -e "$FILE1" ] then echo "requested file doesn't exist" >&2 exit 1 else echo "Found File $FILE1" fi 7: [ ! -e .profile ] 12: echo 'Found File .profile' Found File .profile 

Here, I can see that I set $FILE1 to .profile , and that my script understood that $ . The best thing about this is that it works on all shells down to the original Bourne shell. That means if you aren’t running Bash as you think you might be, you’ll see where your script is failing, and maybe fix the issue.

I suspect you might not be running your script in Bash. Did you put #! /bin/bash on the top?

script.sh [-g] [-p] [-r FUNCTION_ID|-d FUNCTION_ID] FILE

You may want to use getopts to parse your parameters:

#! /bin/bash USAGE=" Usage: script.sh [-g] [-p] [-r FUNCTION_ID|-d FUNCTION_ID] FILE " while getopts gpr:d: option do case $option in g) g_opt=1;; p) p_opt=1;; r) rfunction_id="$OPTARG";; d) dfunction_id="$OPTARG";; [?]) echo "Invalid Usage" 1>&2 echo "$USAGE" 1>&2 exit 2 ;; esac done if [[ -n $rfunction_id && -n $dfunction_id ]] then echo "Invalid Usage: You can't specify both -r and -d" 1>&2 echo "$USAGE" >2& exit 2 fi shift $(($OPTIND - 1)) [[ -n $g_opt ]] && echo "-g was set" [[ -n $p_opt ]] && echo "-p was set" [[ -n $rfunction_id ]] && echo "-r was set to $rfunction_id" [[ -n $dfunction_id ]] && echo "-d was set to $dfunction_id" [[ -n $1 ]] && echo "File is $1" 

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