Simple noob question

I have a long-running command running in an ssh shell (ubuntu). I have another command ready to execute afterwards, eg. sleep 30\n echo 1 or sleep 30; echo 1.

If I ctrl-z the long-running command (eg. sleep), it will of course then execute echo. How can I ctrl-z, bg, and disown both lines such that I can log out of my ssh session without interrupting the process, and still run the second command once the first has finished?

As you may have guessed, the second command is a notification so I know when the first has finished :D

I've found this SU post: https://superuser.com/q/361790, but it doesn't seem to have any useful info on how to do this.

Any points in the right direction would be very appreciated; I'm sure there's an easy way to do this without restarting my long-running command to put it in a noscript.

​

edit: change markdown to rich text

https://redd.it/17d5eva
@r_bash

How to replace tab with space in file only for tabs before letters, not numbers?

I have a file with contents of

X Y Z m
A B n
...

where X, Y, Z and A, B are words and m, n are numbers. They are in a tsv file, so all separated by tabs.

How can I substitute the tabs between the words X, Y, Z and A, B with spaces while keeping the tabs before the numbers m, n intact?

I thought about this (some regex?) but cannot think of a good solution.

EDIT: m,n can be larger than 9, so not necessarily single digits.

https://redd.it/17e204g
@r_bash

Help with noscript to detect if my webcam is currently active

I’m trying to create a shell noscript to run on a schedule. I just want a simple yes/no, on/off, or any kind of Boolean to determine if the camera is in use so I can then run other automations.

Seems this is possible using ps or grep but I haven’t been able to figure it out.

https://redd.it/17e4gbn
@r_bash

What situations call for a subshell?

As I'm following a tutorial on Bash, the topic on subshells has me stumped. For example, the tutorial makes use of a subshell in order to access a database. That leaves me to ask:

When should a subshell be used when running a noscript?
How important are they and what are the consequences of not using them?

https://redd.it/17ed5dy
@r_bash

Hopefully an easy question, though I doubt it

So, I've been re-learning bash noscripting over the past year, and I'm getting fairly proficient again, like being able to write some types of noscripts without having to look most things up anymore, but I've been working on a a couple of noscripts, one of which isn't my own, but I'm kind of modifying the living bejeezus out of it. It's a basic ls alternative called 'formatdir' that was an example in "Wicked Cool Shell Scripts", and I transcribed it to my WSL environment when I started re-learning bash. I'm now working on adding filetype recognition, and several things are easy as pie to get working, like directories, noscripts, pipes, stuff that has a dedicated file test option.

But now I'm starting to get into the weeds, and I'm kinda up to my waist in the river as it were, with trying to figure out like archives for the moment. Is there a way to test whether a file is an archive? Doesn't have to like recognize whether it's a zip or a tarball, I just need to have the noscript identify that "this file is an archive" so I can have it give the output for them the proper color.

https://redd.it/17effgd
@r_bash

Administration tools for Linux (Bash)

Here are a few Bash noscripts for Linux system administration, I am working to release a few more security oriented noscripts. I would appreciate if you could take a look at them and give me feedback. Thank you very much!

https://github.com/javisys/System-Administration-Scripts-Linux

https://redd.it/17ejbrj
@r_bash

How to develop apps for within shell?

I mean something like terminal train. Which language is used? Can you link me to a github repo for something similar?

https://redd.it/17enawo
@r_bash

Command fails in noscript, but succeeds from SSH terminal window. WTH?!

I'm baffled. I have this folder called Documents and it has a directory called, `Dir with (parentheis) and apostrophe's and [square brackets]`. I created this very basic noscript to demonstrate the behavior I am seeing and seek help. Here is the code: ​

# !/bin/sh

dirname=/share/Documents
IFS=$'\n';
for d in $dirname**/Dir*; do echo ls "\"$d\"" 2>&1; ls "\"$d\"" 2>&1; break; done

​ When I run the noscript, I am getting the following: ​

# ~/dateadded.sh
ls "/share/Documents/Dir with (parentheis) and apostrophe's and [square brackets]"
ls: cannot access "/share/Documents/Dir with (parentheis) and apostrophe's and [square brackets]": No such file or directory

When I copy&paste the first line of output from the noscript into the same terminal window's prompt from which the noscript is run, I get this as a result:

# ls "/share/Documents/Dir with (parentheis) and apostrophe's and [square brackets]"
total 20
4 drwxrwxr-x 2 admin administrators 4096 Oct 23 18:33 .
16 drwxrwxrwx 89 tntadmin administrators 12288 Oct 23 18:33 ..

That's what I am expecting from the noscript.

This server is a QNap NAS and I am running the noscript locally via a SSH terminal. I have tried running this with bash and sh. I have run `set` from the Terminal and from within the noscript and piped the output to files and put the differences into the noscript and (aside from the errors about read-only variables) still get the error. Enclosing the directory name in quotes should be sufficient but I even tried piping the directory name to `sed` to escape all the special characters. Still no love. I tried busybox and coreutils `ls` and `bash`. Nothing is working. I even tried running from Docker Containers running Ubuntu and Debian. STILL NO LOVE!

EDIT: I just tried changing the subdirectory of `$dirname` to a directory called `Scanned` that has absolutely no special characters at all. STILL NO LOVE!!!!!

Help?!

https://redd.it/17eyhzn
@r_bash

What's the difference between running `unset array_var` and `unset array_var[*]` given array_var is an array variable?

`array_var` is an array variable.

**First step:**

I unset `array_var` by running this command: `unset array_var[*]`. After that I ran this command: `set | grep array_var` and this was the output:

_=array_var

**Second step:**

I unset `array_var` by running this command: `unset array_var`. And again, I run this command: `set | grep array_var` and I see the same output:

_=array_var

My CLI looks this now:

user@apple:~$ set | grep array_var
user@apple:~$ array_var=(one two three four five)
user@apple:~$ unset array_var[*]
user@apple:~$ set | grep array_var
_=array_var
user@apple:~$ array_var=(one two three four five)
user@apple:~$ unset array_var
user@apple:~$ set | grep array_var
_=array_var
user@apple:~$

So does that mean `unset array_var[*]` and `unset array_var` commands have the same purpose. I am not actually sure about this tho.

Also what does `_=array_var` mean?

Also another important thing I noticed is that, if we follow the steps in a reverse order (second step -> first step) `_=array_var` is not output when `set | grep array_var` is run. So that means `_=array_var` was created only when running `unset array_var[*]`. It will be nice if someone explained this too.

Thanks.

https://redd.it/17fa9w8
@r_bash

Decided to write an IRC client
https://github.com/wick3dr0se/irc-bash

https://redd.it/17ff2g7
@r_bash

My Tips and Tricks for Bash Scripting After Writing Hundreds of Scripts

https://levelup.gitconnected.com/my-tips-and-tricks-for-bash-noscripting-after-writing-hundreds-of-noscripts-59987855b20a?sk=30564b4d311ac550cc2cfe4f0f426970

In this article I share my tips and best practices for writing noscripts in Bash.

https://redd.it/17fj8x0
@r_bash

How do I go about cracking this?

I am given a task as part of my assignment and I am not sure if I didnt understand the question or not, regardless of how much I try I am not able to crack this file. This is the question:

You are given a ciphertext for which you know the start of the corresponding plaintext: “Our shared secret word is: ” (excluding the quotation marks). The remainder of the plaintext consists of a single word from a dictionary file, with no spaces, carriage returns or line feeds added. The plaintext was encrypted using 128-bit AES with CBC mode using a single openssl enc command with no salting used, and using a password (also from the dictionary file) that is shorter than 16 characters, with a single digit from 0-9 appended to the word before encryption. A key was generated from the password using the SHA-256 message digest (as part of the same, single openssl enc command). Your goal is to write a program using a shell noscript that would find the password and the remainder of the plaintext. As part of your noscript you should use the commandline tools provided by openssl to encrypt and decrypt messages in order to perform a brute-force cryptanalysis. I have been at it for I don't know how long and I am unable to crack this.

The files provided are cipher.unknown and a words.txt the file format for the cipher is not given as it just says unknown. Please help me with this. even a simple explanation will be helpful for me. Thanks in advance

https://redd.it/17fmqma
@r_bash

Replacing underscores with " - " in folder and file names

I'm no stranger to bash but I'm out of practice. I'm trying to fix a huge archive of mp3's for someone and a ton of them used underscores and "illegal" characters in directory and filenames where it would read better to have a dash, i.e. "./Working/New/Classic_Country: Great Duets_Earl_Thomas_Conley_&_Tammy_Wynette-We_Believe_In_Happy_Endings.mp3:

Musicbranz Picard fixes all of this at the artist - noscript level, but the directory naming I just can't seem to fix with it's noscripting. I've been using a simple bash noscript to just pull all the files out of the folders into the "New" folder which helps, but the folder structure helps a lot with identifying the albums and artists.

So I've been tinkering with a noscript to loop through the folders and then the files to find any with underscores and special or illegal characters (\^A-Za-z0-9._) and replace them with " - " but I just can't seem to find the right command. I can pull the files or folders I want with something like this

find /home/serenity/Working/New -mindepth 1 -type d -name '*_*'| while read dir ; do echo "$dir" ; done

but I can't seem to apply something like this to it tomove them to a proper dir/name

| sed -e 's/[\^A-Za-z0-9._-\]/ - /g'

https://redd.it/17frvv4
@r_bash

i'm a terrible journalist

### this is my journal editor setup

i keep using this noscript because it opens up the editor and names the file. if there was a previously named file it will show it side by side. keep the noscript here .local/bin/today

#!/usr/bin/env bash
# this journal for today
today=$(date +%Y-%m-%d).md
# last journal entry
past=$(ls -t1 *.md | head -n 1)
# open the editor like
if [ -f "$today" ]; then editor $today; else editor -O $today $past; fi

anybody have similar noscript helpers they use like this

https://redd.it/17fte6r
@r_bash

How can I time the bash processes blocking input

Bash is every now and then freezing while I'm typing a command.

Is there a way to time the "blocking" / unresponsiveness? A total time for the current session in bashrc somehow?


if my bash terminal is frozen waiting for lets say a tab completion on a dead fuse mount, time until its completed as in force closed, killed etc. Sry for my inability to explain it better/correctly.


In short, the time I waste and a way for me to track where its worst and how I can do better / look at whats going on. Maybe check the same in another shell with the history file etc. -Or is this stupidity?


https://redd.it/17g3h9w
@r_bash

This Is My Most Complex Bash Script To Date

I made an Arch install noscript fully in Bash that sets up my system and my dot files with only three simple commands.

The whole thing is hosted on gitlab at https://gitlab.com/mclartydan0505/savageos and the idea is that now anywhere in the world I can get my full system setup from the command line to my custom desktop in minutes.

I know this is kind of moot as an Arch install noscript considering the one that comes by default is pretty good, but this noscript also downloads my Awesome config and all the apps I like with all the configs I like.

It is rather minimal, only installing about 600 packages by default. I am working on adding one file section the chroot to allow the user to add any additional apps they want to install, it is easy to do I just need to find the time to write it and commit it.

​

If you would like to run it in a vm or on hardware I could take the input for any errors, I did a sanity check in a QEMU VM with UEFI and it worked as planned, but I would like to know how hardware responds.

The hardest part is that the archlinux-keyring always seams to be breaking in the live iso, but I think I found a setup that can get the keyring to work 99% of the time so the noscript can download git and run the pacstrap.

https://redd.it/17g6hmw
@r_bash

Sticky shift key or one time caps lock

Hello, I'm trying to modernize a bit the input methods in my computer since we've (or at least I) been suffering for decades the same falencies.

What I want is a method for activating caps lock until a letter is entered and then deactivate it.

**O**btaining this result, without the need to press any combination of keys.

But I don't want sticky shift all the time I just want to be able to choose betwwen different methods.

***E***ven a different implentation of the same code, could work... ***L***ike this. ***I*** mean turning on and off capslock automatically each time that the '. ' sequence is entered.

I wrote a bash noscript to do so that works well in the terminal but when associated with a keyboard shortcut gets totally lost. I think that read has no idea where it is, here is my noscript:

!/bin/bash
echo $caps_state
while true; do
read -rsn1 input
for letter in {A..Z} {a..z}; do
echo $input = $letter
if [[ "$input" == $letter ]]; then
caps_state=$(xset -q|grep Caps|cut -d: -f3|tr -d ' ')
echo $caps_state
if ! [[ $caps_state == off01 ]]; then
echo caps off
xdotool key Caps_Lock
exit
fi
fi

done
done

What keylogger should I use?

https://redd.it/17ge8a1
@r_bash

Sourcing dynamic color in PS1 from noscript (details in comments)
https://redd.it/17gfd86
@r_bash

at plays command immediatley

any one shed any light as to why bash plays the alarm sound immediately rather than waiting for the specified time ?

​

\#!/bin/bash

​

​

strHour=$(zenity --forms --noscript "simple alarm clock" --text "Combo Hoour" --add-combo "Select Hour." --combo-values "00|01|02|03|04|05|06|07|08|09|10|11|12|13|14|15|16|17|18|19|20|21|22|23|24") && echo $strHour

​

​

​

strMinute=$(zenity --forms --noscript "simple alarm clock" --text "Combo Hoour" --add-combo "Select Minute." --combo-values "00|01|02|03|04|05|06|07|08|09|10|11|12|13|14|15|16|17|18|19|20|21|22|23|24|25|26|27|28|29|30|31|32|33|34|35|36|37|38|39|40|41|42|43|44|45|46|47|48|49|50|51|52|53|54|55|56|57|58|59") && echo $strMinute

if zenity --question --text="Set Alarm for $strHour:$strMinute ?"; then

zenity --info --text="You pressed \\"Yes\\"!"

ffplay /home/dunryc/Wip/alarmclock/alarm.wav | at $strHour:$strMinute

else

zenity --info --text="You pressed \\"No\\"!"

fi

​

​

https://redd.it/17gjexs
@r_bash

Question about à Regular Expression

Hi,

I got a question regarding Regular expressions on Bash.
Currently doing the LPI exams, and one of the question is:

- What extented regular expression would match any mail address, like info@example.org ?

So came out with the following regex:

^[[:alnum:]]{1,}@([[:alnum:]]|-|\.){1,}\.[[:lower:]]{2,6}$

- Starts with alphanumeric char (at least 1)

- Followed by @

- Followed by at least one alphanumeric char or an hyphen or a dot

- Ending with 2 to 6 lower cases to match all kinds of domains (.xyz,.de,.com,.org,.museum and more)

In the given solution, here's the regex used:

"^\S+@+\S+\.\S+"

Both regex works, but just by curisoty, what is the most efficient one ? the simplest or the more complex ?

As far as I understood

is used to match any non-whitespace character but does it not includes specials chararacters such as question mark, exclamation mark and so on ? that are forbidden in a mail address ?

https://redd.it/17gv8zy
@r_bash

Learning more

I know the basic stuff (variables, if else, read,echo,etc) how would I learn more and where can I?

https://redd.it/17gxcb2
@r_bash