Possible test scenario:

1. call using from another directory full path /home/user/bin/myscripth.sh
2. add /home/user/bin to PATH and then call from another directory by “myscript.sh”
3. create symlink to script and call using symlink. Check for relative and absolute symlinks.
4. it should work also if it is sourced “source” or “.”

The best is to create setup/installer script which hardcode path to one shared script.

Another solutions:

#!/bin/sh
MY_DIR=$(dirname $(readlink -f $0))
$MY_DIR/other_script.sh

DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )

DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && cd -P "$( dirname "$SOURCE" )" && pwd )"

cur_file="${BASH_SOURCE[${#BASH_SOURCE[@]} - 1]}"
cur_dir="$(dirname "${cur_file}")

`BASH_SOURCE' An array variable whose members are the source filenames where the corresponding shell function names in the `FUNCNAME' array variable are defined. The shell function `${FUNCNAME[$i]}' is defined in the file `${BASH_SOURCE[$i]}' and called from `${BASH_SOURCE[$i+1]}'

DBLBRACKETS

Bash double brackets Bash (extended test command) are safer and provides more features but they are not portable (and not sh compatible). Features:

1. not filename expansion. Strings will be take literally (i.e. “name*”).
2. operators like || instead of -o
3. regex matching =~

[[ -e $file_name ]]

[ -e "$file_name" ]

not compatible with sh

if [[ $string == *"word1 word2"* ]] ...

if [[ $string =~ .*word.* ]] ...