Linux / Unix: Shell Script Find Out In Which Directory Script File Resides

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I need to find out in which directory my bash script resides so that I can read config file called .backup .ignore .target. For example, if my script resides in >/home/foo/script.sh, I need to read /home/foo/.{backup,ignore,target} files. How do I find out the current directory location and shell script directory location in Bash running on Linux or Unix like operating systems?

You can use any one of the following method to find out the portion of pathname:

  1. basename command – Display filename portion of pathname.
  2. dirname command – Display directory portion of pathname.
  3. Bash parameter substitution.
  4. $0 expands to the name of the shell or shell script.

Examples: Shell script find out which directory the script file resides

The following example display directory path or portion of /home/nixcraft/scripts/foo.sh:

dirname /home/nixcraft/scripts/foo.sh

Sample outputs:

/home/nixcraft/scripts

The following line sets the shell variable i to /home/nixcraft/scripts:

i=`dirname /home/nixcraft/scripts/foo.sh`
echo "$i"

OR

i=$(dirname /home/nixcraft/scripts/foo.sh)
echo "$i"

In bash script use $0 instead of /home/nixcraft/scripts/foo.sh:

#!/bin/bash
script="$0"
basename="$(dirname $script)"
 
echo "Script name $script resides in $basename directory."

Sample outputs:

Script name /tmp/test.sh resides in /tmp directory.

Using bash shell ${var%pattern} syntax

To Remove from shortest rear (end) pattern use the following syntax:

var=${path%/*}

For example:

x="/Users/nixcraft/scripts/bar.sh"
echo "${x%/*}"
y="${x%/*}"
echo "$y"

An updated version of the above script:

#!/bin/bash
# Purpose : Linux / Unix shell script find out which directory this script file resides
# Author : nixCraft <http://www.cyberciti.biz> under GPL v2.x+
# -------------------------------------------------------------------------------------
script="$0"
basename="${script%/*}"
config1="${basename}/.backup"
config2="${basename}/.ignore"
config3="${basename}/.target"
 
echo "Script name $script resides in $basename directory."
echo "Reading config file $config1 $config2 $config3, please wait..."

Run it as:
$ chmod +x /tmp/test.sh
$ /tmp/test.sh
Sample outputs:

Fig.01 Sample run from test.sh
Fig.01 Sample run from test.sh

A note about finding physical or real path

You may not get a real physical path and real path may be a symbolic link. To get physical path use realpath command. The realpath command uses the realpath() function to resolve all symbolic links, extra / characters and references to /./ and /../ in path. This is useful for shell scripting and security related applications.

Another recommended option is to use the readlink command to display value of a symbolic link or canonical file name:

#!/bin/bash
# Purpose : Linux / Unix shell script find out which directory this script file resides
# Author : nixCraft <http://www.cyberciti.biz> under GPL v2.x+
# -------------------------------------------------------------------------------------
 
## Who am i? ##
## Get real path ##
_script="$(readlink -f ${BASH_SOURCE[0]})"
 
## Delete last component from $_script ##
_mydir="$(dirname $_script)"
 
## Delete /path/to/dir/ component from $_script ##
_myfile="$(basename $_script)"
echo "Script : $_script"
echo "Directory portion of $_script : $_mydir"
echo "Filename portion of $_script : $_myfile"

Save and close the file. Run it as follows:

./demo.bash
cd /home/vivek/
../../tmp/demo.bash
/tmp/demo.bash

Sample outputs:

Fig.02: Finding real path
Fig.02: Finding real path

See also
  • See man pages for more info – basename(1), dirname(1), bash(1)

Posted by: Vivek Gite

The author is the creator of nixCraft and a seasoned sysadmin and a trainer for the Linux operating system/Unix shell scripting. He has worked with global clients and in various industries, including IT, education, defense and space research, and the nonprofit sector. Follow him on Twitter, Facebook, Google+.

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11 comment

  1. i found aund used the function below. This should be included in the script itself.

    getScriptPath() {
    if [ -d ${0%/*} ]
    then
        abspath=$(cd ${0%/*} && echo $PWD/${0##*/})
        # to get the path only - not the script name - add
        pathOnly=`dirname "$abspath"`
    else
        progdir=`dirname $0`
        cd $progdir
        pathOnly=$PWD
    fi

    echo $pathOnly;
    return
}

    Further down in the script I can use $(getScriptPath) as variable, such as

    mysql database <$(getScriptPath)/query.sql

    Hope this helps:

    Reply Report comment

  3. Hello,

    The problem is that method won’t give your the absolute path if it is started with the relative one.
    For example, if my script is launched with ./test.sh I won’t know from the script where am I really residing in the FS.

    So the response is :
    abspath=$(readlink -f $0)

    Then you can do any basename, dirname an other path manipulation on it.

    Reply Report comment

  5. readlink -f $0 won’t work on Mac OS X.
    A nice one-liner would be

    SCRIPT_PATH=$(cd $(dirname ${0}) && pwd)

    It doesn’t resolve the real path, though. For this you’ll need an OS check or something…

    SCRIPT_PATH=$(cd $(dirname ${0}) && pwd)
echo $SCRIPT_PATH
if [[ ${OSTYPE} = darwin* ]]; then
	TEMP=`readlink ${SCRIPT_PATH}`
	echo $TEMP
	SCRIPT_PATH=${TEMP:-${SCRIPT_PATH}}
else
	SCRIPT_PATH=`readlink -f ${SCRIPT_PATH}`
fi

    Note that OS X’s readlink is not reliable.

    Reply Report comment

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