Unix shell script find out which directory the script file resides?

In Bash, you should get what you need like this:

#!/usr/bin/env bash

BASEDIR=$(dirname "$0")
echo "$BASEDIR"

The original post contains the solution (ignore the responses, they don't add anything useful). The interesting work is done by the mentioned unix command readlink with option -f. Works when the script is called by an absolute as well as by a relative path.

For bash, sh, ksh:

#!/bin/bash 
# Absolute path to this script, e.g. /home/user/bin/foo.sh
SCRIPT=$(readlink -f "$0")
# Absolute path this script is in, thus /home/user/bin
SCRIPTPATH=$(dirname "$SCRIPT")
echo $SCRIPTPATH

For tcsh, csh:

#!/bin/tcsh
# Absolute path to this script, e.g. /home/user/bin/foo.csh
set SCRIPT=`readlink -f "$0"`
# Absolute path this script is in, thus /home/user/bin
set SCRIPTPATH=`dirname "$SCRIPT"`
echo $SCRIPTPATH

See also: https://stackoverflow.com/a/246128/59087