r_bash – Telegram
My noscript uses more CPU than I think it should

I created the below noscript to turn off the keyboard light on my Lenovo Thinkpad P1 when I'm not typing.

https://gist.github.com/tonsV2/cc97bb6dd3fdd82e2e2961d417803eaa

However I see it at the top of my process list using close to 100% of CPU for a lot longer than I'd expect. Can anyone here tell me how to improve it?

https://redd.it/1i1q6u3
@r_bash
Filtering output while outputting it.

So the concept is simple. I have a complex command that generates output to the screen. Within that output is a single piece of data that I want to capture and use later, but not in such a way that it disrupts the flow of output to the screen. If the complex command's not interactive and relatively short, I've found I can do this:

declare OUTPUT=$(complex_command)

declare -i data_captured=$(sed -n -e 's/...//p' <<<"${OUTPUT}")

printf '%s\t%s\n' "${OUTPUT}" "$(do_something_with $data_captured)"

This has the unfortunate side effect that it doesn't work for interactive complex\_command's, nor in long-lasting ones.

I thought what I'd do was, I would pretend to be one of those dea— Wait a minute. Wrong noscript.

I thought what I'd do was open up a file denoscriptor for reading and writing, start the complex\_command in the background with a tee that performs the sed and sends its output to the extra file denoscriptor. Then, in the main-line of the noscript, perform reads from that file denoscriptor and process them as needed, also generating output asynchronously, if necessary. Would that look something like this?

exec 3<&
complex_command | tee >(sed -n -e 's/...//p' >&3) &
while read -u 3; do
do_something_with $REPLY
done

Problem is, that's not what that syntax actually does. The first line does not create the file denoscriptor 3 for reading and writing locally, so the 2nd and 3rd lines complain about non-existent file denoscriptor 3. This is an area where my bash-fu is weak.

What am I missing?

https://redd.it/1i2s0ww
@r_bash
Contribute to my project with bash noscripts

Hello everyone, I hope you are doing well. I need bash devs to contribute with useful noscripts to my bash customization project. It would be appreciated if you can help me in any way. Feel free to propose changes in the project itself, but my main need is to add into the assets/contrib noscripts action. If you decide to help me and contribute, open a PR and I will approve if the noscript fits the project's purpose.

Here is the link: https://github.com/yorevs/homesetup/tree/master/assets/contrib

Thanks for your help.

Edit: Please add your name/contact if you wish, so people know who created it (actually, create a folder with your name and put the noscript in it).

https://redd.it/1i2ssyh
@r_bash
Questions about netcat and ports

Hi there,

I am testing the program netcat and I see something that I do not understand so here I am.

I listen to some ports with :

for j in 20{0..9}{0..5}; do nc -lvn `127.0.0.1` $j & done

Assuming nc will listen to tcp by default.

Then I send data into a listened port :

echo lol | nc `127.0.0.1` 2095

The output :

Connection received on `127.0.0.1` 51404

lol

The question, why is nc responding that the data is received at 127.0.0.1 51404, what is this port ? Same, if I send into port 2070, it will answer at 40630 ? etc..


EDIT : it exits with error code 130

https://redd.it/1i33ysk
@r_bash
what about "case-ignore"?

Hi, why not bash ignore uppercase!

vim or VIM opens vim

ls/LS idem...

exit/EX..

ETC..

I don't know about submission flag maybe was a wrong flag

Regards!

https://redd.it/1i3hwtb
@r_bash
how to catch status code of killed process by bash noscript

Hi every one, I am working on project, and I faced an a issue, the issue is that I cannot catch the exit code "status code" of process that worked in background, take this program as an example, that exits with 99 if it received a sigint, the code:

#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
void bye(){
// exit with code 99 if sigint was received
exit(99);
}
int main(int argc,char** argv){
signal(SIGINT, bye);
while(1){
sleep(1);
}
return 0;
}


then I compiled it using

\`gcc example.c -o byeprogram\`

in the same directory, I have my bash noscript:

set -x
__do_before_wait(){
##some commands
return 0
}
__do_after_trap(){
##some commands
return 0
}
runbg() {
local __start_time __finish_time __run_time
__start_time=$(date +%s.%N)
# Run the command in the background
($@) &
__pid=$!
trap '
kill -2 $__pid
echo $?
__finish_time=$(date +%s.%N)
__run_time=$(echo "$__finish_time - $__start_time" | bc -l)
echo "$__run_time"
__do_after_trap || exit 2
' SIGINT
__do_before_wait || exit 1
wait $__pid
## now if you press ctrl+c, it will execute the commands i wrote in trap
}
out=`runbg /path/to/byeprogram`


my problem is I want to catch or print the code 99, but I cannot, I tried to execute the \`byeprogram\` from the terminal, and type ctrl+c, and it return 99, how to catch the 99 status code??

https://redd.it/1i3isxg
@r_bash
Give a markdown file and create files based on that: Is this possible?

Filename.java
    code goes here

Filename2.java
    code goes here

Filename3.java
    code goes here



The file looks like this. I know chatgpt can do this but I really want myself to learn bash the last time.


- Read the file with read -a command

- when encountered a first-name keep it as touch Filename.java

- Then everything between three backticks are echoed inside that filename.java


And so on.. Do this till you reach last of file.

https://redd.it/1i43g9m
@r_bash
how to change prompt(+command) just before execution (PS0)

Hi, it is easy to invert the colors of my prompt+command: PS1="\e[7m> "; PS0="\e[27m". I want to achieve this look, but only after hitting enter. Does anyone have an idea how to achieve this?

https://redd.it/1i3pr9t
@r_bash
Recommendations for optimizations to bash alias

I created a simple alias to list contents of a folder. It just makes life easier for me.

alias perms="perms"
function perms
{

END=$'\e[0m'
FUCHSIA2=$'\e[38;5;198m'
GREEN=$'\e[38;5;2m'
GREY2=$'\e[38;5;244m'

for f in *; do
ICON=$(stat -c '%F' $f)
NAME=$(stat -c '%n' $f)
PERMS=$(stat -c '%A %a' $f)
FILESIZE=$(du -sh $f | awk '{ print $1}')
UGROUP=$(stat -c '%U:%G' $f)
ICON=$(awk '{gsub(/symbolic link/,"🔗");gsub(/regular empty file/,"");gsub(/regular file/,"📄");gsub(/directory/,"📁")}1' <<<"$ICON")

printf '%-10s %-50s %-17s %-22s %-30s\n' "${END}‎ ‎ ${ICON}" "${GREEN}${NAME}${END}" "${PERMS}" "${GREY2}${FILESIZE}${END}" "${FUCHSIA2}${UGROUP}${END}"
done;
}


It works pretty well, however, it's not instant. Nor is it really "semi instant". If I have a folder of about 30 or so items (mixed between folders, files, symlinks, etc). It takes a good 5-7 seconds to list everything.

So the question becomes, is their a more effecient way of doing this. I threw everything inside the function so it is easier to read, so it needs cleaned.

Initially I was using sed for replacements, I read online that awk is faster, and I had originally used multiple steps to replace. Once I switched to awk, I added all the replacements to a single command, hoping to speed it up.

And originally, I was using a single stat command, and using all of the flags, but then if you had files of different lengths, then it started to look like jenga, with the columns mis-aligned. That's when I broke it up into different calls, that way I could format it with printf.

Originally it was:
file=$(stat -c ' %F  %A     %a    %U:%G         %n' $1)


So I'm assuming that the most costly action here, is the constant need to re-run stat in order to grab another piece of information.

Any pointers would be great. Hopefully I can get this semi-fast. It seems stupid, but it really helps with seeing my data.


https://redd.it/1i4nou3
@r_bash
Export ain't working I'm so confused

So apparently if you change a variable and then export it, then say you open a new terminal then the variable would have changed, but this didn't work for me, even with child processes like so:

I did:

PS1="Bash is cool! "

export PS1

Then:

qterminal

but the shell prompt was still default

and even if I did the following but instead of qterminal I wrote "bash" (to show a new prompt), then it was still the same.


Why???

https://redd.it/1i5gder
@r_bash
Help with Permission Issue in Bash Script (Cronjob)

Hey everyone, I’ve been stuck on an issue for a while and hope someone here can help me out. I’m trying to run a Bash noscript with Cron that creates Restic backups and stores a PID file. However, I keep getting the following error: Line 60: /var/tmp/restic_backup.pid: Permission denied I’ve already verified that /var/tmp/ has the correct permissions: drwxrwxrwt 16 root root 4096 Jan 20 10:50 /var/tmp The cron job is running as the correct user (poan). I’ve also tried changing the noscript to write in other directories like /tmp/ or /home/poan/tmp/, but the error still persists. Does anyone have any ideas on what I might be overlooking or what else I can try to resolve the issue? Any tips would be greatly appreciated! Thanks in advance!

https://redd.it/1i5n4c1
@r_bash
Command substitution problem

I do have a problem that drives me crazy:

I have a binary that needs to be run in a bash noscript, but in some case fails and then needs to be run in a chroot for the rest of the noscript.

When it first fails I set a variable RUN_IN_CHROOT=yes.

I catch the output of the binary via command substitution.

So my noscript looks like this:

MY_BINARY=/path/to/binary
mode=$(${MY_BINARY} -m $param1)

If that doesn't work:
RUN_IN_CHROOT=yes

mode=$(${RUN_IN_CHROOT:+chroot} ${RUN_IN_CHROOT:+/mnt} ${MY_BINARY} -m $param1)

So from this point every call to the binary has the RUN_IN_CHROOT checks and should prepend the chroot /mnt.

But I get the error: chroot /mnt: No such file or directory

It treats both as a single command, which can obviously not be found.

When I run with bash -x I see that it tries to call 'chroot /mnt' /path/to/binary -m 8

Why does it encapsulate it in this weird way, and how can I stop it from doing so?

Thanks for your help.

Sorry for the lack of formatting.

https://redd.it/1i5ohag
@r_bash
I made a simple "UI Library" for bash called basil. And a small helper for sourcing the library and creating a ready to run file.

Black and white mode

normal mode

retro mode

BASIL

https://redd.it/1i5sn8w
@r_bash
rmdir "No such file or directory" but ls shows folder isn't empty

I am trying to clean up some old media files.

When I use ls to show the contents of my current folder, it lists one folder. When I use rmdir to remove that folder, it states:

ls: folder: No such file or directory


How do I get rid of the target directory?

https://redd.it/1i61br6
@r_bash
Error oh my bash theme development

Good evening everyone, I'm making another theme for Oh My Bash that has the same base as my old theme, but it's not overwriting the base properly, these are the codes



New theme



if [ -z "${NEKONIGHT_BASE_LOADED}" ]; then
source ~/.oh-my-bash/themes/nekonight/nekonight-base.sh
export NEKONIGHT_BASE_LOADED=true
fi


icon_start="╭─"
icon_user=" 🌙 ${_omb_prompt_bold_olive}\u${_omb_prompt_normal}"
icon_host=" at 🌙 ${_omb_prompt_bold_cyan}\h${_omb_prompt_normal}"
icon_directory=" in 🌙 ${_omb_prompt_bold_magenta}\w${_omb_prompt_normal}"
icon_end="╰─${_omb_prompt_bold_white}λ${_omb_prompt_normal}"

_omb_theme_nekonight_git_prompt_info
_omb_theme_nekonight_scm_git_status

function _omb_theme_PROMPT_COMMAND() {
PS1="${icon_start}${icon_user}${icon_host}${icon_directory} in $(_omb_theme_nekonight_git_prompt_info)\n${icon_end} "
}

_omb_util_add_prompt_command _omb_theme_PROMPT_COMMAND





Base theme


 shell
icon_start="╭─"
icon_user=" 🐱 ${_omb_prompt_bold_olive}\u${_omb_prompt_normal}"
icon_host=" at 🐱 ${_omb_prompt_bold_cyan}\h${_omb_prompt_normal}"
icon_directory=" in 🐱 ${_omb_prompt_bold_magenta}\w${_omb_prompt_normal}"
icon_end="╰─${_omb_prompt_bold_white}λ${_omb_prompt_normal}"

function _omb_theme_nekonight_git_prompt_info() {
local branch_name
branch_name=$(git symbolic-ref --short HEAD 2>/dev/null)
local git_status=""

if [[ -n $branch_name ]]; then
git_status="${_omb_prompt_bold_white}(🐱 $branch_name $(_omb_theme_nekonight_scm_git_status))${_omb_prompt_normal}"
fi

echo -n "$git_status"
}

function _omb_theme_nekonight_scm_git_status() {
local git_status=""

if git rev-list --count --left-right @{upstream}...HEAD 2>/dev/null | grep -Eq '^[0-9]+\s[0-9]+$'; then
git_status+="${_omb_prompt_brown}↓${_omb_prompt_normal} "
fi

if [[ -n $(git diff --cached --name-status 2>/dev/null) ]]; then
git_status+="${_omb_prompt_green}+${_omb_prompt_normal}"
fi

if [[ -n $(git diff --name-status 2>/dev/null) ]]; then
git_status+="${_omb_prompt_yellow}•${_omb_prompt_normal}"
fi

if [[ -n $(git ls-files --others --exclude-standard 2>/dev/null) ]]; then
git_status+="${_omb_prompt_red}⌀${_omb_prompt_normal}"
fi

echo -n "$git_status"
}





The prompt gets all buggy, it looks like this


\\\[\\e\[97;1m\\\](🐱 main \\\[\\e\[0;31m\\\]↓\\\[\\e\[0m\\\] \\\[\\e\[0;93m\\\]•\\\[\\e\[0m\\\]\\\[\\e\[0;91m\\\]⌀\\\[\\e\[0m\\\])\\\[\\e\[0m\\\]\\\[\\e\[0;31m\\\]↓\\\[\\e\[0m\\\] \\\[\\e\[0;93m\\\]•\\\[\\e\[0m\\\]\\\[\\e\[0m\\\]╭─ 🌙 brunociccarino at 🌙 DESKTOP-27DNBRN in 🌙 \~ in (🐱 main ↓ •⌀)

╰─λ


https://redd.it/1i6wedj
@r_bash
style enforcement tool?

Hi folks, looking for a sh and bash enforcement tool. I found bashate but seems too limited.

https://redd.it/1i5yexv
@r_bash