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So true. Every time I have to look up how to write a bash for loop. Where does the semicolon go? Where is the newline? Is it terminated with
done? Or withend? The worst part with bash is that when you do it wrong, most of the time there is no error but something completely wrong happens.It all makes sense when you think about the way it will be parsed. I prefer to use newlines instead of semicolons to show the blocks more clearly.
for file in *.txt do cat "$file" doneThe
doanddoneserve as the loop block delimiters. Such as{and}in many other languages. The shell parser couldn’t know where stuff starts/ends.Edit: I agree that the
then/fi,do/donecase/esacare very inconsistent.Also to fail early and raise errors on uninitialized variables, I recommend to add this to the beginning of your bash scripts:
set -euo pipefailOr only this for regular sh scripts:
set -eu-e: Exit on error-u: Error on access to undefined variable-o pipefail: Abort pipeline early if any part of it fails.There is also
-xthat can be very useful for debugging as it shows a trace of every command and result as it is executed.set -euo pipefailFun fact, if you’re forced to write against POSIX shell, you aren’t allowed to use these options, since they’re not a thing, which is (part of) the reason why for example Google doesn’t allow any shell language but bash, lol.
Btw, all three set options given above are included in POSIX since 2024: https://pubs.opengroup.org/onlinepubs/9799919799/
Ooh, you’re totally right!! I forgot about that since it’s not in the older versions.
I can only remember this because I initially didn’t learn about
xargs— so any time I need to loop over something I tend to usefor var in $(cmd)instead ofcmd | xargs. It’s more verbose but somewhat more flexible IMHO.So I run loops a lot on the command line, not just in shell scripts.
My google history hits for powershell for loop is is in the dozens.
Je comprend tellement! Je répond en français pour ma première réponse sur Lemmy juste pour voir comment ça va être géré!
I so understand! Answering I. French for my first Lemmy reply just to see how it’s handled.
Realizing now that language selection is mainly for people filtering. It be cool if it auto translated for people that need it.
Si yo también comprendo, qué necesidad de comentar todo el tiempo en anglais?
En un mundo ideal. Todo se traduciría automáticamente del idioma original al idioma del lector y viceversa
Knowing that there is still a bash script i wrote around 5 years ago still running the entirety of my high scool lab makes me sorry for the poor bastard that will need to fix those hieroglyphs as soon as some package breaks the script. I hate that i used bash, but it was the easiest option at the time on that desolate server.
Bash scripts survive because often times they are the easiest option on an abandoned server
Bash was the first language I learned, got pretty decent at it. Now what happens is I think of a tiny script I need to write, I start writing it in Bash, I have to do string manipulation, I say fuck this shit and rewrite in Python lol
Meh. I had a bash job for 6 years. I couldn’t forget it if I wanted to. I imagine most people don’t use it enough for it to stick. You get good enough at it, and there’s no need to reach for python.
The older you get, the more things are like programming in bash.
The sad thing is that even chatgpt can’t program in bash. I just want a simple script and every single time it just doesn’t work. I always just end up saying “write this in python instead”.
Python’s usually the better choice anyway tbf. I know piping isn’t as good, but there are so many footguns!
Nushell and Fish can be really convenient too.
I used to adhere to sh for an OpenBSD machine but I switched to python, Rust and Go for, even simple things.
Python is just as portable these days (on modern hardware, caveats, caveats).
Honestly so intuitive that I start there too unless I have a need for speed or distinct memory control. There’s no job too small for a python script.
Clearly you don’t write enough bash scripts.
Enough is enough
I’ve had enough of these motherfucking scripts on this motherfucking PC!
When I bash my head into a wall, does that count?
Only if you scripted it
Or scripts for basically any other variant of the Bourne shell. They are, for the most part, very cross compatible.
That’s the only reason I’ve ever done much of anything in shell script. As a network administrator I’ve worked many network appliances running on some flavor of Unix and the one language I can count on to be always available is bash. It has been well worth knowing for just that reason.
I wrote a script to do backups on a ESXi it uses Busybox’s ASH, one thing I learned after spending hours debugging my scripts was that ASH does not support arrays so you have to do everything with temporary files.
There actually is an array in any POSIX shell. You get one array per file/function. It just feels bad to use it. You can abuse ‘set – 1 2 3 4’ to act as a proper array. You can then use ‘for’ without ‘in’ to iterate over it.
for i; do echo $i; done.
Use shift <number> to pop items off.
If I really have to use something more complex, I’ll reach for mkfifo instead so I can guarantee the data can only be consumed once without manipulating entries.
I feel same with regex…
I don’t normally say this, but the AI tools I’ve used to help me write bash were pretty much spot on.
Yeah, an LLM can quickly parrot some basic boilerplate that’s showed up in its training data a hundred times.
Yes, with respect to the grey bearded uncles and aunties; as someone who never “learned” bash, in 2025 I’m letting a LLM do the bashing for me.
Until the magic incantations you don’t bother to understand don’t actually do what you think they’re doing.
Sounds like a problem for future me. That guy hates me lol
Yeah fuck that guy
Yes, I have never wrote a piece of code that didn’t do what I thought it would before LLMs, no sir.
In fairness, this also happens to me when I write the bash script myself 😂
I wonder if there’s a chance of getting
rm -rf /*or zip bombs. Those are definitely in the training data at least.The classic
rm -rf $ENV/homewhere$ENVcan be empty or contain spaces is definitely going to hit someone one day
For building a quick template that I can tweak to my needs, it works really well. I just don’t find it to be an intuitive scripting language.
Unironically love powershell
For a defacto windows admin my Powershell skills are…embarrassing lol but I’m getting there!
Ever since I switched to Fish Shell, I’ve had no issues remembering anything. Ported my entire catalogue of custom scripts over to fish and everything became much cleaner. More legible, and less code to accomplish the same things. Easier argument parsing, control structures, everything. Much less error prone IMO.
Highly recommend it. It’s obviously not POSIX or anything, but I find that the cost of installing fish on every machine I own is lower than maintaining POSIX-compliant scripts.
Enjoy your scripting!
I wish I could but since I use bash at work (often on embedded systems so no custom scripts or anything that isn’t source code) I just don’t want to go back and forth between the two.
If you’re going to write scripts that requires installing software, might as well use something like python though? Most Linux distros ship also ship with python installed
A shell script can be much more agile, potent, and concise, depending on the use case.
E.g. if you want to make a facade (wrapper) around a program, that’s much cleaner in
$SHELL. All you’re doing is checking which keyword/command the user wanted, and then executing the commands associated with what you want to achieve, like maybe displaying a notification and updating a global environment variable or something.Executing a bunch of commands and chaining their output together in python is surely much more cumbersome than just typing them out next to each other separated by a pipe character. It’s higher-level. 👍
If it’s just text in text out though, sure, mostly equivalent, but for me this is rarely the use case for a script.
I’m not anti bash or fish, I’ve written in both just this week, but if we’re talking about readability/syntax as this post is about, and you want an alternative to bash, I’d say python is a more natural alternative. Fish syntax is still fairly ugly compared to most programming languages in my opinion.
Different strokes for different folks I suppose.
I’ve been meaning to check out
fish. Thanks for the reminder!Happy adventuring! ✨
I switched to fish a while back, but haven’t learned how to script in it yet. Sounds like I should learn
I love fish but sadly it has no proper equivalent of
set -eas far as I know.|| return;in every line is not a solution.It’s the default on CachyOS and I’ve been enjoying it. I typically use zsh.
Regex
Don’t let the gatekeepers keep you out. This site helps.
Chatgpt helps even more
I know that LLMs are probably very helpful for people who are just getting started, but you will never understand it if you can’t grasp the fundamentals. Don’t let “AI” make you lazy. If you do use LLMs make sure you understand the output it’s giving you enough to replicate it yourself.
This may not be applicable to you specifically, but I think this is nice info to have here for others.
twitch
This is one of the best uses for LLM’s imo. They do all my regex for me.
You get used to it, I don’t even see the code—I just see: group… pattern… read-ahead…
No. Learn it properly once and you’re good. Also it’s super handy in vim.
interns gonna intern
Most of regex is pretty basic and easy to learn, it’s the look ahead and look behind that are the killers imo
(?=)for positive lookahead and(?!)for negative lookahead. Stick a<in the middle for lookbehind.
You always forget regex syntax?
I’ve always found it simple to understand and remember. Even over many years and decades, I’ve never had issues reading or writing simple regex syntax (excluding the flags and shorthands) even after long regex breaks.
It’s not about the syntax itself, it’s about which syntax to use. There are different ones and remembering which one is for which language is tough.
I give you that, true. I wish vim had PCRE
There is the “very magic” mode for vim regexes. It’s not the exact PCRE syntax, but it’s pretty close. You only need to add \v before the expression to use it. There is no permanent mode / option though. (I think you can remap the commands, like / to /\v)
This is exactly it. Regex is super simple. The difficulty is maintaining a mental mapping between language/util <-> regex engine <-> engine syntax & character class names. It gets worse when utils also conditionally enable extended syntaxes with flags or options.
The hardest part is remembering whether you need to use
\wor[:alnum:].Way too few utils actually mention which syntax they use too. Most just say something accepts a “regular expression”, which is totally ambiguous.
And I thought I was the only one… for smaller bash scripts chatGPT/Deepseek does a good enough job at it. Though I still haven’t tried VScode’s copilot on bash scripts. I have only tried it wirh C code and it kiiiinda did an ass job at helping…
AI does decently enough on scripting languages if you spell it out enough for it lol, but IMO it tends to not do so well when it comes to compiled languages
I’ve tried Python with VScode Copilot (Claude) and it did pretty good
That’s because scripted languages are more forgiving in general.
I was chalking it up to some scripting languages just tending to be more popular (like python) and thus having more training data for them to draw from
But that’s a good point too lol
Both can be true, Python does have a lot of examples floating online.
