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How can I set the current working directory to the directory of the script in Bash?

I'm writing a Bash script. I need the current working directory to always be the directory that the script is located in.

The default behavior is that the current working directory in the script is that of the shell from which I run it, but I do not want this behavior.

Have you considered putting a wrapper script somewhere like /usr/bin to cd into the (hardcoded) proper directory and then execute your script?
Why do you need the directory of the script? There's probably a better way to solve the underlying problem.
I'd just like to point out that the behavior you call "obviously undesirable" is in fact entirely necessary -- if I run myscript path/to/file I expect the script to evaluate path/to/file relative to MY current directory, not whatever directory the script happens to be located in. Also, what would you have happen for a script run with ssh remotehost bash < ./myscript as the BASH FAQ mentions?
cd "${BASH_SOURCE%/*}" || exit

n
ndim
#!/bin/bash
cd "$(dirname "$0")"

dirname returns '.' when using bash under Windows. So, Paul's answer is better.
Also returns '.' in Mac OSX
It's worth noting that things can break if a symbolic link makes up part of $0. In your script you may expect, for example, ../../ to refer to the directory two levels above the script's location, but this isn't necessarily the case if symbolic links are in play.
If you called the script as ./script, . is the correct directory, and changing to . it will also end up in the very directory where script is located, i.e. in the current working directory.
If you run the script from the current directory like so bash script.sh, then the value of $0 is script.sh. The only way the cd command will "work" for you is because you don't care about failed commands. If you were to use set -o errexit (aka: set -e) to ensure that your script doesn't blow past failed commands, this would NOT work because cd script.sh is an error. The reliable [bash specific] way is cd "$(dirname ${BASH_SOURCE[0]})"
R
Richard

The following also works:

cd "${0%/*}"

The syntax is thoroughly described in this StackOverflow answer.


Explanation how it works: stackoverflow.com/questions/6393551/…
Don't forget to enclose in quotes if the path contains whitespace. i.e. cd "${0%/*}"
This fails if the script is called with bash script.sh -- $0 will just be the name of the file
neither it works if a script is in the root directory, because "${0%/*}" would expand to empty string
I would say this answer is too succinct. You hardly learn anything about the syntax. Some description about how to read this would be helpful.
k
kenorb

Try the following simple one-liners:

For all UNIX/OSX/Linux

dir=$(cd -P -- "$(dirname -- "$0")" && pwd -P)

Bash

dir=$(cd -P -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd -P)

Note: A double dash (--) is used in commands to signify the end of command options, so files containing dashes or other special characters won't break the command.

Note: In Bash, use ${BASH_SOURCE[0]} in favor of $0, otherwise the path can break when sourcing it (source/.).

For Linux, Mac and other *BSD:

cd "$(dirname "$(realpath "$0")")";

Note: realpath should be installed in the most popular Linux distribution by default (like Ubuntu), but in some it can be missing, so you have to install it.

Note: If you're using Bash, use ${BASH_SOURCE[0]} in favor of $0, otherwise the path can break when sourcing it (source/.).

Otherwise you could try something like that (it will use the first existing tool):

cd "$(dirname "$(readlink -f "$0" || realpath "$0")")"

For Linux specific:

cd "$(dirname "$(readlink -f "$0")")"

Using GNU readlink on *BSD/Mac:

cd "$(dirname "$(greadlink -f "$0")")"

Note: You need to have coreutils installed (e.g. 1. Install Homebrew, 2. brew install coreutils).

In bash

In bash you can use Parameter Expansions to achieve that, like:

cd "${0%/*}"

but it doesn't work if the script is run from the same directory.

Alternatively you can define the following function in bash:

realpath () {
  [[ $1 = /* ]] && echo "$1" || echo "$PWD/${1#./}"
}

This function takes 1 argument. If argument has already absolute path, print it as it is, otherwise print $PWD variable + filename argument (without ./ prefix).

or here is the version taken from Debian .bashrc file:

function realpath()
{
    f=$@
    if [ -d "$f" ]; then
        base=""
        dir="$f"
    else
        base="/$(basename "$f")"
        dir=$(dirname "$f")
    fi
    dir=$(cd "$dir" && /bin/pwd)
    echo "$dir$base"
}

Related:

How to detect the current directory in which I run my shell script?

Get the source directory of a Bash script from within the script itself

Bash script absolute path with OS X

Reliable way for a Bash script to get the full path to itself

See also:

How can I get the behavior of GNU's readlink -f on a Mac?


a much better answer than the popular ones because it resolves syslinks, and accounts for different OS's. Thanks!
Thanks for this answer. The top one worked on my Mac... but what does the -- switch do in the cp command, @kenorb?
A double dash (--) is used in commands to signify the end of command options, so files containing dashes or other special characters won't break the command. Try e.g. create the file via touch "-test" and touch -- -test, then remove the file via rm "-test" and rm -- -test, and see the difference.
I'd remove my upvote if I could: realpath is deprecated unix.stackexchange.com/questions/136494/…
@lsh It says that only Debian realpath package is deprecated, not GNU realpath. If you think it's not clear, you can suggest an edit.
J
John Kugelman
cd "$(dirname "${BASH_SOURCE[0]}")"

It's easy. It works.


This should be the accepted answer. Works on OSX and Linux Ubuntu.
This works great when the script B is sourced from other script A and you need to use paths relative to script B. Thank you.
This also works in Cygwin for those of us unfortunate enough to have to touch Windows.
Or cd "${BASH_SOURCE%/*}" || exit
Works on macOS Mojave
J
James McGuigan

The accepted answer works well for scripts that have not been symlinked elsewhere, such as into $PATH.

#!/bin/bash
cd "$(dirname "$0")"

However if the script is run via a symlink,

ln -sv ~/project/script.sh ~/bin/; 
~/bin/script.sh

This will cd into the ~/bin/ directory and not the ~/project/ directory, which will probably break your script if the purpose of the cd is to include dependencies relative to ~/project/

The symlink safe answer is below:

#!/bin/bash
cd "$(dirname "$(readlink -f "${BASH_SOURCE[0]}")")"  # cd current directory

readlink -f is required to resolve the absolute path of the potentially symlinked file.

The quotes are required to support filepaths that could potentially contain whitespace (bad practice, but its not safe to assume this won't be the case)


A
Amardeep AC9MF

This script seems to work for me:

#!/bin/bash
mypath=`realpath $0`
cd `dirname $mypath`
pwd

The pwd command line echoes the location of the script as the current working directory no matter where I run it from.


realpath is unlikely to be installed everywhere. Which may not matter, depending on the OP's situation.
My system doesn't have realpath but it does have readlink which seems to be similar.
Which dist doesn't have realpath installed by default? Ubuntu has it.
A
Andrew Theken

There are a lot of correct answers in here, but one that tends to be more useful for me (making sure a script's relative paths remain predictable/work) is to use pushd/popd:

pushd "$(dirname ${BASH_SOURCE:0})"
trap popd EXIT

# ./xyz, etc...

This will push the source file's directory on to a navigation stack, thereby changing the working directory, but then, when the script exits (for whatever reason, including failure), the trap will run popd, restoring the current working directory before it was executed. If the script were to cd and then fail, your terminal could be left in an unpredictable state after the execution ends - the trap prevents this.


R
Robert Hu

I take this and it works.

#!/bin/bash
cd "$(dirname "$0")"
CUR_DIR=$(pwd)

C
Community

Get the real path to your script

if [ -L $0 ] ; then
    ME=$(readlink $0)
else
    ME=$0
fi
DIR=$(dirname $ME)

(This is answer to the same my question here: Get the name of the directory where a script is executed)


佚名
cd "`dirname $(readlink -f ${0})`"

Can you explain your answer please ?
Although this code may help to solve the problem, it doesn't explain why and/or how it answers the question. Providing this additional context would significantly improve its long-term educational value. Please edit your answer to add explanation, including what limitations and assumptions apply.
${0} would give the file name of the script. readlink -f {0} would give that script's absolute path. dirname would extract the script located path from previous result.
B
Binary Phile

Most answers either don't handle files which are symlinked via a relative path, aren't one-liners or don't handle BSD (Mac). A solution which does all three is:

HERE=$(cd "$(dirname "$BASH_SOURCE")"; cd -P "$(dirname "$(readlink "$BASH_SOURCE" || echo .)")"; pwd)

First, cd to bash's conception of the script's directory. Then readlink the file to see if it is a symlink (relative or otherwise), and if so, cd to that directory. If not, cd to the current directory (necessary to keep things a one-liner). Then echo the current directory via pwd.

You could add -- to the arguments of cd and readlink to avoid issues of directories named like options, but I don't bother for most purposes.

You can see the full explanation with illustrations here:

https://www.binaryphile.com/bash/2020/01/12/determining-the-location-of-your-script-in-bash.html


J
Julian
echo $PWD

PWD is an environment variable.


This only gives the directory called from, not the directory where the script is.
K
Keith Smiley

If you just need to print present working directory then you can follow this.

$ vim test

#!/bin/bash
pwd
:wq to save the test file.

Give execute permission:

chmod u+x test

Then execute the script by ./test then you can see the present working directory.


The question was how to ensure the script runs in its own directory, including if that is not the working directory. So this is not an answer. Anyway, why do this instead of just... running pwd? Seems like a lot of wasted keypresses to me.