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Comment by netcoyote | Hacker News Reader

Should use $BASH_SOURCE in place of $0 so it works in files that are sourced.

The incantation at the top of all my scripts, that I learned from other HN folks, is:

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

And I guess throw a realpath in there too for symlinks, per TFA.

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/bin/sh on FreeBSD isn't bash.

On MacOS, we had interoperability uses between different versions somehow, and some of us could not use `realpath` .

The following worked for everyone:

  SCRIPT_DIR=$(dirname "$(readlink -f "${BASH_SOURCE[0]}")").

You don't need realpath. The `cd` into the directory + `pwd` is equivalent.

BASH_SOURCE[0] obviously only works with bash.

> You don't need realpath

Yes you do (or a suitable alternative, e.g. GNU readlink).

> The `cd` into the directory + `pwd` is equivalent.

You won't know which directory to cd to without realpath. Just stripping off the filename does not get you the correct directory if the file itself is a symlink, which is a common use case.

Doh, you're right. Thank you for the correction.

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