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

by on August 4, 2013 · 10 comments· LAST UPDATED August 12, 2013

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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?

Tutorial details
DifficultyEasy (rss)
Root privilegesNo
RequirementsNone
Estimated completion timeN/A
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..."
 

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

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{ 10 comments… read them below or add one }

1 Russ Thompson August 5, 2013 at 12:40 am

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

2 nixCraft August 12, 2013 at 11:40 am

Russ, I appreciate that you are sharing your code with us.

Reply

3 Mahdi August 5, 2013 at 6:35 am

Thank you for this!

Reply

4 Michel Nicolas August 6, 2013 at 10:46 am

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

5 nixCraft August 12, 2013 at 11:41 am

Thanks for the heads up. The faq has been updated. I appreciate your post.

Reply

6 Chris F.A. Johnson August 18, 2013 at 11:17 pm

If a script needs to know where it is located, it is badly designed.

Reply

7 Michel Nicolas August 19, 2013 at 5:04 am

Chris,

Can you tell me why would it be badly designed? Jugement without deep knowledge about the facts are useless.

Nicolas

Reply

8 Russ Thompson October 16, 2013 at 3:48 pm

I feel if a script has to be edited when moved from directory to directory to operate correctly it is badly designed.

Reply

9 Chris F.A. Johnson October 16, 2013 at 6:15 pm

If a script has to be moved from directory to directory, it is badly designed. Scripts should always be placed in a directory in your PATH variable, so they can be called from anywhere.

Reply

10 Latchezar Tzvetkoff October 16, 2013 at 12:55 pm

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

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