#!/usr/bin/env bash

A folder dotfiles as git repository and a dotfiles/install that soft links all configurations into their places.

Two files, ~/.zshrc (without secrets, could be shared) and another for secrets (sourced by .zshrc if exist secrets).

Use shellcheck

Do you use bash?

Personally I use Bash for scripting. It strikes the balance of being available on almost any system, while also being a bit more featureful than POSIX. For interactive use I bounce between bash and zsh depending on which machine I’m on.

Do you write #!/bin/bash or #!/bin/sh?

I start my shell scripts with #! /usr/bin/env bash. This is the best way of ensuring that the same bash interpreter is called that the user expects (even if more than one is present or if it is in an unusual location)

Do you have two folders, one for proven commands and one for experimental?

By commands, do you mean bash scripts? If so, I put the ones I have made relatively bulletproof in ~/bin/, as bash usually makes them automatically on the path with this particular folder name. If I’m working on a script and I don’t think it’s ready for that, or if it goes with a specific project/workflow, I will move it there.

Do you sync the folder between your server and your workstation?

No. I work on lots of servers, so for me it’s far more important to know the vanilla commands and tools rather than expect my home-made stuff to follow me everywhere.

good practice? general advice?

Pick a bash style guide and follow it. If a line is longer than 80 characters, find a better way of writing that logic. If your script file is longer than 200 lines, switch to a proper programming language like Python. Unless a variable is meant to interact with something outside of your script, don’t name it an all caps name.

is it bad practice to create a handful of commands like podup and poddown that replace podman compose up -d and podman compose down or podlog as podman logs -f --tail 20 $1 or podenter for podman exec -it "$1" /bin/sh?

This is a job for bash aliases.

I use bash for scripts almost exclusively even though i use zsh interactively (startup scripts for zsh are an obvious exception).

The vast majority of my scripts start with

  set -e -u

which makes the script exit if a command (that is not in a few special places like an if) exits with an error status code and also complains about unbound variables when you use them.

Use

bash -n

and

shellcheck

to test your script for errors and problems if you try it.

Always use curly braces for variables to avoid issues with strings after the variable name being interpreted as part of the variable name.

Always use 10# before numbers in $(()) expressions to avoid leading zeroes turning your decimal number variables into octal ones.

Always use

while read -r foo
do
...
done < <(command ...)

instead of

command ... | while read -r foo
do
...
done

to avoid creating a subshell where some changes you make will not affect your script outside the loop.

In

while read -r foo
do
...
done < ...

loops always make sure you redirect all stdin from /dev/null or otherwise close it with suitable parameters or the content of your loop will eat some of the lines you meant for the read. Alternatively fill a bash array in the loop and then use a for loop to call your commands and do more complex logic.

When using temporary directories or similar resources use

cleanup()
{
 ...
}
trap cleanup EXIT

handlers to clean up after the script in case it dies or is killed (by SIGTERM or SIGINT,…; obviously not SIGKILL).

When writing scripts for cronjobs take into account that the environment (PATH In particular) might be more limited. Also take into account that stderr output and non-zero exit status can lead to an email about the cronjob.

Use pushd and popd instead of cd (especially cd …), redirect their output to /dev/null. This will prevent your scripts from accidentally running later parts of the script in a wrong directory.

There are probably many other things to consider but that is just standard stuff off the top of my head.

If you do need any sort of data structure and in particular arrays of data structures use a proper programming language. I would recommend Rust since a compiled language is much easier to run on a variety of systems than the Python so many others here recommend, especially if you need to support the oldest supported version of an OS and the newest one at the same time.

Use

set -x

For debugging

Several things

• write bash and nothing else (except posix sh)
• find a good way to take notes. It shouldn’t be in your bashrc
• only write fish for fish config
• use $!/usr/bin/env bash

• I use bash, because I never had the time to learn anything else.
• Like @[email protected] said, I use the #!/usr/bin/env bash shebang.
• Nope
• Also nope
• Nope. Shell scripts reside in Git repos on Gitlab/Gitea/Forgejo and are checked out using Ansible playbooks onto the servers as necessary.
• For scripts? Python. Read this blog post by the great @[email protected]. For interactive use? bash is just fine for me, though I’ve customized it using Starship and created some aliases to have colored/pretty output where possible.
• Use shellcheck before running your scripts in production, err on the side of caution, set -o pipefail. There are best practices guides for Bash, use those and you’ll probably be fine.
• Be prepared to shave yaks. Take breaks, touch grass, pet a dog. Use set -x inside your Bash script or bash -x scriptname on the CLI for debugging. Remember that you can always fallback to interactive CLI to test/prepare commands before you put them into your script. Think before you type. Test. Optimize only what needs optimization. Use long options for readability. And remember: Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows your address.
• Nope, it’s absolutely not bad practice to create aliases to save you some typing in interactive shell. You shouldn’t use them inside your scripts though, because they might/will not be available in other environments.

I switched to fish because it has tab completion Yeah, so does Bash, just install it.

Oh, I also “curate” a list of Linux tools that I like, that are more modern alternatives to “traditional” Linux tools or that provide information I would otherwise not easily get. I’ll post i

___

That’s the way I do it:

#!/usr/bin/env nix
#! nix shell nixpkgs#nushell <optionally more dependencies>  --command nu

<script content>

But those scripts are only used by me

Shell scripts are one of the things that makes Linux what it is. They’re relatively easy to create, powerful, etc. It was the thing that drove me to it from Windows in the first place.

One thing I would recommend against is creating dozens of utility scripts and/or aliases for things you run frequently. I have found it’s much better in the long-run to simply learn the “proper” commands and switches. If you use them often enough you start to type them very quickly. When you create helpers you start to learn your own ecosystem and will be lost on any system that doesn’t have your suite of helper apps installed.

There are exceptions to this to be sure (e.g. I always alias ‘l=ls -FhlA’) but I would specifically avoid the podup and poddown ones myself. I’ve gotten very quick at typing “docker run -it --rm foo” just by rote repetition.

You’re free to do as you like though. Maybe you’ll only run Linux on your own desktop so that’s all that matters. But something to keep in mind. I would at least learn the commands very well first and then later alias or script them for convenience.

I use Bash for scripts, though my interactive shell is Fish.

Usually I use #!/usr/bin/env bash as shebang. This has the advantage of searching your PATH for Bash instead of hardcoding it.

My folders are only differentiated by those in my PATH and those not.

Most of my scripts can be found here. They are purely desktop use, no syncing to any servers. Most would be useless there.

For good practice, I’d recommend using set -euo pipefail to make Bash slightly less insane and use shellcheck to check for issues.
This is personal preference, but you could avoid Bashisms like [[ and stick to POSIX sh. (Use #!/usr/bin/env sh then.)

With shortened commands the risk is that you might forget how the full command works. How reliant you want to be on those commands being present is up to you. I wouldn’t implement them as scripts though, just simple aliases instead.
Scripts only make sense if you want to do something slightly more complex over multiple lines for readability.

I primarily operate in strict standard compliance mode where I write against the shell specifications in the lastest Single Unix Specification and do not use a she-bang line since including one results in unspecified, implementation-defined behavior. Generally people seem to find this weird and annoying.

Sometimes I embrace using bash as a scripting language, and use one of the env-based she-bangs. In that case, I go whole-hog on bashisns. While I use zsh as my interactive shell, even I’m not mad enough to try to use it for scripts that need to run in more than one context (like other personal accounts/machines, even).

In ALL cases, use shellcheck and at least understand the diagnostics reported, even if you opt not to fix them. (I generally modify the script until I get a clean shellcheck run, but that can be quite involved… lists of files are pretty hard to deal with safely, actually.)

Am I missing something - doesn’t bash have tab completion or of the box?

• I usually use bash/python/perl if I can be sure that it will be available on all systems I intend to run the scripts. A notable exception for this would be alpine based containers, there it’s nearly exclusively #!/bin/sh.
• Depending on the complexity I will either have a git repository for all random scripts I need and not test them, or a single repo per script with Integrationtests.
• Depends, if they are specific to my setup, no, otherwise the git repository is public on my git server.
• Usually no, because the servers are not always under my direct control, so the scripts that are on servers are specific to that server/the server fleet.
• Regarding your last question in the list: You do you, I personally don’t, partly because of my previous point. A lot of servers are “cattle” provisioned and destroyed on a whim. I would have to sync those modifications to all machines to effectively use them, which is not always possible. So I also don’t do this on any personal devices, because I don’t want to build muscle memory that doesn’t apply everywhere.

You are way over thinking it.

• Fish. Much, much saner defaults.
• I am writing #!/usr/bin/env sh for dead simple scripts, so they will be a tiny bit more portable and run a tiny bit faster. The lack of arrays causes too much pain in longer scripts. I would love to use Fish, but it lacks a strict mode.
• No, why would I?
• I used to share all my dotfiles, scripts included, but I was too afraid that I would publish some secrets someday, so I stopped doing that. For synchronizing commands, aliases and other stuff between computers I use Chezmoi.
• To use Fish instead of fighting with start up time of Zsh with hundreds of plugins
• Always use the so-called “strict mode” in Bash, that is, the set -euo pipefail line. It will make Bash error on non-zero exit code, undefined variables and non-zero exit codes in commands in pipe. Also, always use shellcheck. It’s extremely easy to make a mistake in Bash. If you want to check the single command exit code manually, just wrap it in set +e and set -e.
• Consider writing your scripts in Python. Like Bash, it also has some warts, but is multiplatform and easy to read. I have a snippet which contains some boilerplate like a main function definition with ArgumentParser instantiated. Then at the end of the script the main function is called wrapped in try … except KeyboardInterrupt: exit(130) which should be a default behavior.
• Absolutely not a bad practice. If you need to use them on a remote server and can’t remember what they stand for, you can always execute type some_command. Oh, and read about abbreviations in Fish. It always expands the abbreviation, so you see what you execute.