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

Question

Basically I need to run the script with paths related to the shell script file location, how can I change the current directory to the same directory as where the script fil

Answer 1

Let's make it a POSIX oneliner:

a="/$0"; a=${a%/*}; a=${a#/}; a=${a:-.}; BASEDIR=$(cd "$a"; pwd)

Tested on many Bourne-compatible shells including the BSD ones.

As far as I know I am the author and I put it into public domain. For more info see: https://www.jasan.tk/posts/2017-05-11-posix_shell_dirname_replacement/