This is a simple shell script snippet to get the full absolute path of that file while running it in a shell environment.

What is the use of this script -- Yeah, this script is really helpful when you are looking for a stable deployment of a multi-file project in a Unix based system. For these type of deployments you have to deal with the SYSTEM_PATH and PROJECT_HOME_DIR etc, to make our project run properly by including relative files correctly from the system path. Commonly what we do is, we hard code the SYSTEM PATH information to a Global variable so that would resolve every relative path properly. So how it would be, if we don't need to hard code the Project Bases paths, instead the project configurations detect it automatically :). So you could get this by using this shell script snippet.

Here we can test how a shell script identify itself where it's located or its absolute path information.Please create a shell script with following content and run it from different locations.

#Add this content in a shell.sh,
#and then run it from different directory level, you can see the
#difference.

curr_dir=`pwd`

dir=`dirname $0`
FILE_PATH=`cd  $dir;pwd`

echo "Path to this file : $FILE_PATH"

Add this script to /usr/local/ and run it ( We know that its current locations is /usr/local/)

# cd /
#sh /usr/local/shell.sh
Absolute PATH : /usr/local
#cd /usr
# sh local/shell.sh
Absolute PATH : /usr/local
#cd local
#sh shell.sh
Absolute PATH : /usr/local

I hope the output of the script explained everything. So you can use it in your projects to detect the current path automatically. Hope you enjoyed this hack.