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Comment by alexis_fr | Hacker News Reader

At the beginning of each file:

    #!/bin/bash
    set -euf -o pipefail
    cd $(dirname $0)

Then add "" everywhere ;) And they say, write Python instead, except I’m dubious because python programs can have a lot of dependencies which can be tricky to install.

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Your recommendations are a little off in the following ways:

You should use /usr/bin/env bash for the shebang. Some distros, such as nixos, don't have /bin/bash.

You need more quoting in the dirname line. cd "$(dirname "$0")" is what you need. The outer quotes are in case the directory has a space or special character in it, the inner ones are in case the script does.

That being said, you may also want $BASH_SOURCE rather than $0, but the reasons behind that are complicated. You may also want to support cases where the script is a symlink depending on what you're doing.

Using 'env bash' to find the local path is definitely the way to go. It also supports that occasional case where the user has installed modern bash somewhere in their local path (under their home directory) and finds that rather than the system copy.

    #!/usr/bin/env bash

If you really want a predictable environment I usually go with something like this after the shebang, it supports bash and not-bash shells:

    case "$(readlink /proc/$$/exe)" in */bash) set -euo pipefail ;; *) set -eu ;; esac
    PATH=/usr/sbin:/usr/bin:/sbin:/bin
    \unalias -a

I don't usually cd anywhere unless I need to.

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