r_bash – Telegram
Visualize (convert) list of files as tree hiearchy

tree -afhDFci <dir> produces a list of files in the following format:

894 Apr 20 2024 /media/wd8000-1/music/unsorted/
2.0K Apr 20 2024 /media/wd8000-1/music/unsorted/A/
19M Apr 20 2024 /media/wd8000-1/music/unsorted/A/AA.mp4
...

I run this command on an external drive to save it into a text file before unplugging it so I can grep it to see what files I have on the drive along with basic metadata. It's an 8 TB drive with 20k+ files.

I would like a way to visualize the tree structure (e.g. understand how it's organized), e.g. convert it back to the standard tree command output with directory hierarchy and indentation. Or show list of directories that are X levels deep. Unfortunately I won't have access to the drives for a month so I can't simply save another tree output to another file (I also prefer to parse from one saved file).

Any tips? Another workaround would be parse the file and create the file tree as empty files on the filesystem but that wouldn't be efficient.

https://redd.it/1kkerqz
@r_bash
What's the weirdest or most unexpected thing you've automated with Bash?

If we don't count all sysadmin tasks, backups, and cron jobs... what's the strangest or most out-of-the-box thing you've noscripted?

I once rigged a Bash noscript + smart plug to auto-feed my cats while I was away.

https://redd.it/1kkpg7l
@r_bash
.config files in $XDGCONFIGHOME

This is not technically a bash question, but it's shell related and this place is full of smart people.

Let's say I'm writing a noscript that needs a .config file, but I want the location to be in $XDG_CONFIG_HOME/noscriptname.

Leading dots are great for reducing clutter, but that's not an issue if the file is in an uncluttered subdirectory

What's the accepted best practice on naming a config file that sits inside a config directory - with a leading dot or not? I don't see any advantages to leading dots in this case, but decades of noscripting tells me that config files start with a dot ;-)

Note: I'm interested in people's opinions, so please don't reply with a ChatGPT generated opinion

https://redd.it/1km1u0s
@r_bash
how to parallelize a for loop in batches?

On a Proxmox PVE host, I'd like to do scheduled live migrations. My "oneliner" already works, but I've got 2 NICs in adaptive-alb, so I can do 2 migrations at the same time, I presume nearly doubling the speed.

This oneliner will "serialize" the migrations of all VMs it finds on a host (except VM with VMID 120).

Question: how do I change the oneliner below so it does 2 parallel migrations, if those finish, continue with the next two VMs. Ideally, if one finishes, it could immediately start another migration, but it's OK if I can do 100, 101, wait, then 102, 103 wait, then 104 and 105, ... until all VMs are done.

time for vmid in $(qm list | awk '$3=="running" && $1!="120" { print $1 }'); do qm migrate $vmid pve3 --online --migration_network 10.100.80.0/24 --bwlimit 400000; done



https://redd.it/1km88ka
@r_bash
I'm thinking to start to work as a freelancer with shelll scrippting. Realistically, is there a market for that out there?

Just adding to the noscript: I'm thinking about doing this from home on sites like Upwork, Fiverr, **Freelancer.com**, Toptal, and PeoplePerHour. Working in an organization isn't an option at the moment.

I have some portfolio to show, but let's say the noscript's purposes are kind of shallow to show in this context, I'd guess. They're noscripts to help my day-to-day flow. The code itself is fine, most are pure-bash and performance-sensitive noscripts, but their purpose.. Anyway, if you guys say that's an issue, I can find projects to engage in. It's a good way to learn anyway, which is never enough. Thankfully, I have no rush to start working. I've been solely on Linux for around 10 years, and improving or switching my portfolio is not a huge deal.

https://redd.it/1kmdrxc
@r_bash
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[Update] Added Security for dotfold (Previously No Security)
https://redd.it/1kmqmbc
@r_bash
Advance a pattern of numbers incrementally

Hi, I am trying to advance a pattern of numbers incrementally.



The pattern is: 4 1 2 3 8 5 6 7



Continuing the pattern the digits should produce: 4,1,2,3,8,5,6,7,12,9,10,11,16,13,14,15... onwards etc.



What I am trying to archive is to print a book on A4 paper, 2 pages each side so that's 4 pages per sheet when folded and then bind it myself. I have a program that can rearrange pages in a PDF but I have to feed it the correct sequence and I am not able to do this via the printer settings for various reasons hence setting up the PDF page order first. I know I can increment a simple sequence in using something like:



for i in \seq -s, 1 1 100; do echo $i; done

But obviously I am missing the the important arithmetic bits in between to repeat the pattern



Start with: 4

take the 1st input and: -3

take that last input +1

take that last input +1

take that last input +5 etc etc



I am not sure how to do this.



Thanks!

https://redd.it/1kn6ozs
@r_bash
help with noscript to verify rom, output variable, and flash

I tried to write a bash noscript that verifies a rom file using sha256sum.
The output should go into a variable
If the variable contains data exit
Else, flash the rom.
i cant seem to get the output variable to work correctly

I'm still learning bash noscript, so if anyone has any ideas on how to make it work, or improve it?
Thank you

\#!/bin/bash

output=`$(cat *.sha256) *.rom | sha256sum --check --status`
\#output=`ls`

if ! test -z "$output"
then
echo $output
exit
fi

echo "sha256sum correct"
echo
read -p "Are you sure you want to flash? [y/n\]" -n 1 -r
echo

if [[ $REPLY =\~ \^[Yy\]$ \]\]
then
echo
\#flashrom -w *.rom -p internal:boardmismatch=force
echo
echo "finished"
fi

https://redd.it/1kphj67
@r_bash
Stop auto execute after exit ^x^e

Hi, \
As noscript, how do I stop Bash from auto executing command after I'm done editing using ^x^e?

https://redd.it/1kph7k1
@r_bash
Version managers ARE SLOW

It really is too much. You add one nvm here, another rbenv there and top it of with some zoxide. I had to wait about one second just for my shell to start up! That really is suckless-less.

Well, I thought you could fix that problem by lazy-loading all those init noscripts. But when writing all that directly in bash, it quickly gets kind of bloated and not really easy to maintain. So, I've gotten to write a simple lazy-loader to do all that for you.

With lazysh (very creative name), you can list your init noscripts inside of your bashrc (or your shell's rc-file) with the lazy loader and it figures out which commands a single init command modifies by itself and caches the result such that your shell will start up blazingly fast next time!

You can view the project on Github. After installing, you simply add the following lines to your *rc-file and put in your init commands (replacing bash with zsh or fish, respectively):

source $(echo '

# Initializing zoxide
eval "$(zoxide init bash)"

# Initializing rbenv
eval "$(rbenv init - bash)"

# ... any other init command

' | lazysh bash)

https://redd.it/1kpmq9g
@r_bash
Check if gzipped file is valid (fast).

I have a tgz, and I want to be sure that the download was not cut.

I could run tar -tzf foo.tgz >/dev/null. But this takes 30 seconds.

For the current use case, t would be enough to somehow check the final bytes. Afaik gzipped files have a some special bytes at the end.

How would you do that?

https://redd.it/1kqbdib
@r_bash
Bash Shell Scripting and Automated Backups with Cron: Your Comprehensive Guide

I just published a comprehensive guide on Medium that walks through bash shell noscripting fundamentals and how to set up automated backups using cron jobs.
If you have any questions or suggestions for improvements, I'd love to hear your feedback!
PS: This is my first time writing an article
Link: https://medium.com/@sharmamanav34568/bash-shell-noscripting-and-automated-backups-with-cron-your-comprehensive-guide-3435a3409e16

https://redd.it/1kqihm6
@r_bash
is there any naming convention for functions in bash noscripting?

Hello friends, I'm a c programmer who every once in a while makes little bash noscripts to automatize process.

right now I'm making a noscript a bit more complex than usual and I'm using functions for the first time in quite a while. I think it's the first time I use them since I started learning c, so it does bother me a bit to find that the parenthesis are used to define the function and not to call it and that to call a function you just have to write the name.

I have the impression that when reading a code I might have a difficult time remembering that the line that only has "get_path" is a call to the get_path function since I'm used to using get_path() to call said function. So my question is, is there any kind of naming convention for functions in bash noscripting? maybe something like ft_get_path ?

https://redd.it/1kqnyw5
@r_bash
Minimal Bash noscript to convert media files using yt-dlp + ffmpeg

Hey folks!!, I just wrote my first Bash noscript and packaged it into a tool called `m2m`.

It's a simple command-line utility that uses yt-dlp and ffmpeg to download and convert videos.



GitHub repo: https://github.com/Saffron-sh/m2m



It's very minimal, but I’m open to feedback, improvements, and general bash advice. Cheers!



https://redd.it/1kpjxq4
@r_bash
Any tips for a new bash enthusiast_?

Never will I ever use vim for text editing again 🥴.

Nano is my favorite for now, until I become a "pro" in bash noscripting 😁.

I heard this is the place to be to get proper help with bash, anyone here have time to teach me a bit more about it please.

https://redd.it/1kqqlbj
@r_bash
Simplest way to make your noscripts nicer (to use)?
https://redd.it/1kr89kx
@r_bash
Do you actually use getopts in your noscripts?

I always see getopts in discussions, but in real life most noscripts that I come across are just parsing $@ manually. Curious if anyone actually uses it regularly, or if it's more of a 'looks good in theory' kind of thing.

https://redd.it/1ksm8f2
@r_bash
Run non bash command from noscript

Hello,


Newbie here, who started bash noscripting. I am trying to call cowsay from a noscript I am working on. It's just a basic noscript which reads input from a user and spits it out with cowsay. However the fails at the cowsay line with error command not found. Cowsay has been added to path as I am able to call it from anywhere in the terminal without issues. How do I get it to run from the noscript?

Thanks.

https://redd.it/1kt0mq1
@r_bash
Help parsing a string in Bash

Hi,

I was hopign that i could get some help on how to parse a string in bash.

I woudl like to take an input string and parse it to two different variables. The first variable is TITLE and the second is TAGS.

The properties of TITLE is that it will always appear before tags and can be made of multiple words. The properties of the TAGS is that they may

For example the most complext input string that I can imagine would be somethign like the following

This is the noscript of the input string +These +are +the +tags

The above input string needs to be parsed into the following two variables

TITLE="This is the noscript of the input string"
TAGS="These are the tags"

Can anyone help?

Thanks

https://redd.it/1kt449m
@r_bash
need for speed

hello everyone,

let me start by saying that I'm not a coder

I wrote the following fetch noscript with scroll effect just for fun:

>https://codeberg.org/ldm/scr0ll



I also published it on r/unixporn, but I received some comments complaining about the speed...

is this problem due to a badly written noscript? or is bash slow? can the noscript be further optimized?

https://redd.it/1ktghg0
@r_bash
Exit Code for CLI Applications

I've been doing a lot of devops and bash lately, and I'm dissatisfied with the lack of standards around exit codes. Yes, there are some sensible standards such as exit codes over 68 and 126 mapping to signal and OS related failures, but what about custom exit codes?

Obviously 0 is everything went well, but how do you handle cases where the noscript ran as predicted (without crashing) but a distinct/warning-like outcome took place, and an exit code should inform the user on the kind of error that came accross.

I say this because 1 is the catch-all "something went wrong", but at the same time that means your successful but noteworthy exit codes are separated from 0 since you set them to 2,3,4...

Is there some solution I'm missing? I'm starting to settle towards:

0 - success

1 - catchall error

2-67 - custom output state, successful execution but important enough that automated noscripts will want to know about it.

Take diff for example: 0 means inputs are the same, 1 if different, 2 if trouble. Well for most other programs, 1 means they shit the bed. So I'm a little confused.

https://redd.it/1kt9n4c
@r_bash