license-generator: a bash noscript that will generate license for your next open source project

Just wrote this shell noscript which can generate license files. It uses Github's API to fetch license files and make modifications by adding name of project author & year to it. Here's the Github link.

Hadn't written in bash for a long time now, I would love to hear you guys' thoughts on the code. Thanks in advance!

https://redd.it/18ubien
@r_bash

Local -n vs declare -n

Whats the difference between local -n and declare -n when used inside the function?

Bash manual doesnt explain the difference when -n attribute is used for both.

https://redd.it/18to3jj
@r_bash

Generating PNG files with text and "colorful emojis"

I know how to do it with a wide choice of options, but my emojis are all black and white and flat.

I want to get them colorful like on my phone.

I have a trannoscript of a WA chat. I have written code that converts the entire conversation into audio. Now I want to create a video to go with it, containing the actual messages sent back and forth including the emojis, and I really need them to be in color. For reasons!

​

Edit: After searching the depths of the web, I found a tool in imagemagick called Pango that supports this in current versions. I will test it out over the weekend and revert.

https://redd.it/18tku9y
@r_bash

forkrun: the fastest pure-bash loop parallelizer ever written -- looking for "beta testers"

[LINK TO GITHUB REPO WITH CODE](https://github.com/jkool702/forkrun/tree/forkrun-v2_RC)

***

A year ago I started working on `forkrun` - a pure bash (well, almost pure bash) function that works to parallelize loops in much the same way that `xargs -P` and `parallel` do. 1 year, nearly 400 github commits, 1 complete rewrite, and I imagine several hundred hours worth of optimizing later, I do believe that `forkrun` (v2.0) is finally ready to be released.

Before I officially release it, Id love it if a few people would try it out and report any bugs they encounter. Ive thoroughly tested it on my Fedora 39 rig running bash 5.2.x, but other distros and older versions of bash is largely untested (NOTE: min bash version capable of running this is 4.0 due to the use of coprocs) .

Thanks in advance to anyone willing to test it out for me!

***

**USAGE**

There is detailed info in the github readme, but heres some brief usage instructions:

First, source `forkrun.bash` by running one of the following:

. <(curl https://raw.githubusercontent.com/jkool702/forkrun/forkrun-v2_RC/forkrun.bash)

or

wget https://raw.githubusercontent.com/jkool702/forkrun/forkrun-v2_RC/forkrun.bash
. ./forkrun.bash

or

git clone https://github.com/jkool702/forkrun.git --branch=forkrun-v2_RC
. ./forkrun/forkrun.bash

Then use it like you would `xargs`. The base (no flags) `forkrun` is roughly equivalent to `xargs -P $(nproc) -d $'\n'`. After sourcing it, you can display the full usage help (that described the available flags to tweak `forkrun`'s behavior) by running

forkrun --help=all

***

**EXAMPLE**

To compute the `cksum` of every file under the current directory, you would run

find ./ -type f | forkrun cksum

***

P.S. and yes, it really is that fast. My main speed testing has been computing 11 different checksums on ~500,000 mostly small files saved on a tmpfs ramdisk with a total combined size of ~19 gb. The speedtest code + results are [in the github repo](https://github.com/jkool702/forkrun/blob/forkrun-v2_RC/forkrun.speedtest.bash), but to summarize:

* on average it was 70% faster than `xargs -P $(nproc) -d $'\n'`, which is the fastest loop parallelizer I know of (not counting `forkrun`). For the lighter weight checksums like `cksum` and `sum -s` is was closer to 3x faster. Note that this is the fastest implementation of `xargs` (it isnt being crippled by using `-l 1` or `-n 1`), and `xargs` itself is a compiled C binary. Thats right, `forkrun` parallelizes loops faster than the fastest compiled C loop parallelizer I could find.
* on average it is \~7x as fast as `parallel -m`. For the lighter weight checksums like `cksum` and `sum -s` is was >18x faster.
* on my hardware, `forkrun` was computing the lightweight checksums (`cksum` and `sum -s`) on all ~19 gb worth of ~500,000 files in about 1.1 seconds (outputting to `wc -l`), not printing to the terminal)

As such, In can all but guarantee this is the fastest loop parallelizer written in bash that has ever been written. See the github readme if you are curious what makes `forkrun` so fast.

Note: "fast" is referring to "wall clock time". In terms of CPU time `xargs` is a bit better (though not *that* much), but forkrun parallelizes things so well it is faster in "real" execution time.

EDIT: fixed formatting issue.

https://redd.it/18sfjtz
@r_bash

Script to relink broken alias files with new path?

Hi, is there any way to get this done? I have no experience with noscripting, but together with ChatGPT I failed massively to get this done in Terminal on OSX (10.14.6)

From a stupid user perspective:

1. Open Finder-GUI to choose Folder (including subfolder) for damaged/unliked Alias files
2. Check those files for unlinked Aliases.
3. Open Finder-GUI to choose Folder (incl. subfolders) which contains the new destination of the original files.
4. Do the work - restore all Alias links with the new original paths (only for those files, which had a damaged Alias of course).

I cannot find a software that claims to do that on OSX. I am so desperately in need of this function because I work with a software which relies on Aliases for it's internal file management system, and after I did some major reorganisation of my hard drives, I'm left with hundrets of unlinked Aliases..... :(

https://redd.it/18w0sog
@r_bash

Pipe output to a file with auto incremented name?

I like doing > temp-file.txt for output of some commands that I might need later.

This has progressed to > ../tmp/2024-01-01-001.txt, but writing the timestamps and index numbers gets tedious.

Is there a utility or noscript that would let me do just > keep or something similar? Seems like a common use case but after a couple of google searches I didn't find anything.

https://redd.it/18w3vt5
@r_bash

Collection Scrips

Hey Guzs , I am collection bash noscripts that shortens the tasks

here is contribution link Bash-Baby

https://redd.it/18wm2p0
@r_bash

Trouble formatting output of PS command

I'm trying to get a formatted list of the 5 most CPU intensive processes using the PS command. This works but I'm not sure how to align all values to the left.

I run the command like so:

ps --no-headers -Ao comm:21, -o pid:6, -o pcpu:6 --sort=-pcpu | head -5

which produces the following output:

Isolated Web Co 97231 7.9
firefox 32302 5.5
Isolated Web Co 175732 3.7
Hyprland 689 2.1
RDD Process 45174 1.9

Now I'd like to align the second column to the left but I'm not sure how to do this. Piping it into column -t messes up the layout because of the spaces in the first column's values:

Isolated Web Co 97231 8.1
Isolated Web Co 175732 5.7
firefox 32302 5.4
Hyprland 689 2.1
RDD Process 45174 2.0

I'm probably missing something obvious. Can anyone point me in the right direction? It would be much appreciated!

https://redd.it/18xwvec
@r_bash

Monitor filesystem events using inotify-tools

# inotify-tools
This is a basic guide to use inotify-tools.

```bash
apt-get install inotify-tools
```

## Initial Command
This is basic command of inotify-tools.

* `inotifywait` is a part of inotify-tools.
* `-m` monitor for events continuously (don't exit after the first event).
* `-e create` watch for file creation events specifically.
* `/path/to/directory` The directory to monitor.
```bash
inotifywait -m -e create /path/to/directory
```

When a new file is created, inotifywait will print a line like -
```
CREATE /path/to/directory/new_file.txt
```
Capture this output in a noscript or command to perform actions on the new file.

## Using while loop
```bash
inotifywait -m -e create /path/to/directory | while read line; do
# Extract the filename from the output
filename=$(echo $line | cut -d' ' -f3)
# Do something with the new file
echo "New file created: $filename"
done
```

## Additional options
* `-r` Monitor recursively for changes in subdirectories as well.
* `--format %f` Print only the filename in the output.
* `--timefmt %Y%m%d%H%M%S` Specify a custom timestamp format.

https://redd.it/1ad1pgp
@r_bash

Create bash noscripts 100x faster using libray

# bash-sdk 🔥

A bash library to create standalone noscripts.

https://ourcodebase.gitlab.io/bashsdk-docs/

## Features ✨

There are some features of bash-sdk are mentioned here.

OOPS like code 💎.
Module based code 🗂️.
Similar functions to python 🐍.
Standalone noscript creation 📔.

## Beauty 🏵️

Checkout the ui of this cli project here.

## General 🍷

There are some rules or things to keep in mind while using this library.

The rules are mentioned here.

## Installation 🌀

Just clone it to anywhere.

git clone --depth=1 https://github.com/OurCodeBase/bash-sdk.git

## Modules 📚

These are the modules created in bash-sdk library. You can read about their functions by clicking on them.

[ask.sh](/docs/ask)
cursor.sh
[db](/docs/db)
file.sh
[inspect.sh](/docs/inspect)
os.sh
[package.sh](/docs/package)
repo.sh
[say.sh](/docs/say)
screen.sh
[spinner.sh](/docs/spinner)
string.sh
[url.sh](/docs/url)

## Structure 🗃️

File structure of bash-sdk is like:

bash-sdk
├── docs # docs for bash-sdk.
├── _uri.sh # helper of builder.
├── builder.sh
└── src
├── ask.sh
├── cursor.sh
├── db.sh
├── file.sh
├── inspect.sh
├── os.sh
├── package.sh
├── repo.sh
├── say.sh
├── screen.sh
├── spinner.sh
├── string.sh
└── url.sh

## Compiler 🧭

Compiler does combine all codes in a standalone bash file.

bash builder.sh -i "path/to/input.sh" -o "path/to/output.sh";

input file is the file that you are going to compile.
output file is the standalone result file.

Then you can directly execute output file without bash-sdk library.

## Queries 📢

If you have any questions or doubt related to this library you can directly ask everything [here](https://github.com/OurCodeBase/bash-sdk/issues).

## Suggestion 👌

bash-lsp to your code editor to get auto completions.
[shellcheck](https://github.com/koalaman/shellcheck) to debug bash code.
cooked.nvim code editor to get best compatibility.

## Author 🦋

Created By [@OurCodeBase](https://github.com/OurCodeBase)
Inspired By @mayTermux

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

BEE-GENTLE-1ST-BASH-SCRIPT

so, I am looking to make my life a bit simple, I use nmap and use some pentesting labs. IP of target always changes and instead of remembering the ip of the target, it would be nice to just use TARGET in my commands that I pass.

I sudo this file and it was giving me ability to append a new targetname and ip to /etc/hosts file
e.g. target1 10.10.10.101

I tried it and it worked, so I added in a command where I need some guidance, pointers on how I can add the delete option. I googled and saw sed command but not sure how to incorporate it.

My expectation is to cat the /etc/hosts file and see whats there, then add or delete as needed before a new pentest box is being worked on.

filename: addtarget.sh
#!/bin/sh
echo "What is the TARGET # please"
read TARGET
echo "Enter IP address please"
read IP
/new line added to delete/ echo "Enter TARGET # to delete from /etc/hosts"
/new line added to delete/ read DEL
/new line added to delete/ sed -i.bak '/target$DEL\'./d' /etc/hosts # will delete lines containing "target."

echo "Adding $TARGET and its associated $IP address for you"
echo "$TARGET $IP" >> /etc/hosts

++++++++++++++++++++++
Thank you in advance to this community and any support you can provide me.

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

Utility that Scans A Bash Script And Lists All Required Commands

#### I'm looking for a utility that scans a bash noscript and lists all required commands. Some reqs and specs, v00.03.

Do you know of such a beast?

I have not been able to frame a valid web query, other than ones that generate terabytes of cruft.

Barring that, I could use some help with specs.

**Shortcuts?**

* I can safely ignore or disallow command names and functions with embedded spaces.
* Would running the bash '-x' option provide a better basis for the scan, or is the source better?
* Or, what?
* I have a few noscripts that write other noscripts (templates, with an intervening editing session). I suppose that if I have a utility that can scan a "non-recursive" noscript, I could use the utility recursively?

**"Specs"**

* I only want the list to include external commands; if Bash internals are included, I would prefer that they be listed separately.
* There are quite a few Bash internals that have external equivalents, e.g., 'echo' and 'test'. I need to be able to distinguish between the two like-named commands. Is a format like '/bin/test', for example, sufficient to distinguish between the two?
* Ignore first <words> followed by '()'
* Ignore everything to the right of a '#' not quoted or escaped.
This gets pretty complicated on multiline quotes with embedded quotes, i.e.:
- \>"...'...'..."<
- \>"...'...'..."<
- \>"...\"...<
- etc.
* First <word> on a line.
* First <word> following a ';'.
* First <word> following a '|'.
* First <word> following a '$(', or '`'.

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

bash noscript developer

Hi I am a researcher and I have to write some bash noscripts for my project but I am too new here. Could you please help me (as a consultant or paid bash noscript writer)?

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

Iterating over ls output is fragile. Use globs.

My editor gave me this warning, can y'all help me understand why?

The warnig again is:

`Iterating over ls output is fragile. Use globs.`

Here is my lil noscript:

#!/usr/bin/env bash
for ZIPFILE in $(ls *.zip)
do
echo "Unzipping $ZIPFILE..."
unzip -o "$ZIPFILE"
done

What should I use instead of `$(ls *.zip)` and why?

https://redd.it/1abus2n
@r_bash

A Bash noscript thatspurpose is to source the latest release version number of a GitHub repository

To use it set the variable url (or name it whatever)

repo example 1
url=https://github.com/rust-lang/rust.git
repo example 2
url=https://github.com/llvm/llvm-project.git

And run this command in your bash noscript

curl -sH "Content-Type: text/plain" "https://raw.githubusercontent.com/slyfox1186/noscript-repo/main/Bash/Misc/source-git-version.sh" | bash -s "$url"

These examples should return the following version numbers for llvm and rust respectively...

17.0.6

1.75.0

It works for all the repos I have tested so far but I'm sure one will throw an error.

If a repo doesn't work let me know and I'll see if I can fix it.

https://redd.it/1abhv75
@r_bash

finding files and [sub]directories with exclusions

So, I recently discovered while using `find` and trying to exclude a particular directory via something like

find "${base_dir}" ! -path "${exclude_dir}" ! -wholename "${exclude_dir}/*"

that `find` still scans the excluded directory and then removes them from the output. i.e., it doesnt "skip" this directory, it scans it like all the rest and then removes any results that match the `! -path` or `! -wholename` rule.

This can be a bit annoying (and make the `find` run *really* slow) if the directory you are excluding is, for example:

* the mount point of a huge mounted zfs raidz2 pool storing some 40 TB of data
* the mount point of a 5 tb usb attached HDD to an embedded system that can only read it at a maximum of ~20 MB/s

Being that I ran into both of these in the last few days, In wrote up a little function to exclude directories from find without having to scan through them. That said, its decently robust but Im sure some edge cases will give it trouble, and I feel there is probably a tool that does this more robustly, so if anyone knows what it is by all means let me know.

The function below works by figuring out a minimal file/directory list that is searched (with `find`) that covers everything under the base search dir except the excluded stuff. For example: if you wanted to list everything under `/a/b` except for `a/b/c`, `a/b/d/e`, `a/b/d/f`, and any subdirectories under those three exclusions, this list of "files and directories to search" would include:

* everything immediately under `/a/b` except for `/a/b/c` and `/a/b/d` \-\-AND\-\-
* everything immediately under `/a/b/d`, except for `/a/b/d/e` and `/a/b/d/f`

This function constructs this list by breaking apart excluded directories into "nesting levels" relative to the base search dir and then on each doing `find -mindepth 1 -maxdepth 1 ! -path ...` in a loop on each unique dir from each nesting level.

***

OK, heres the code:

efind () {
## find files/directories under a base search directory with certain files and directories(+sub-directories) excluded
#
# IMPORTANT NOTE:
# excluded directories are not queried at all, making it fast in cases where the excluded directory contains A LOT of data
# (unlike `find "$base_dir" ! -path "$exclude_dir/*"`, which traverses the excluded directory and then drops the results)
#
# USAGE:
# 1st input is the base search directory that you are searching for things under
# All remaining inputs are excluded files and/or directories
#
# dependencies: `realpath` and `find`

local -a eLevels edir efile A B F;
local bdir a b nn;
local -i kk;

shopt -s extglob;

# get base search directory
bdir="${1%\/}";
shift 1;
[[ "${bdir}" == \/* ]] || bdir="$(realpath "${bdir}")";

# parse additional inputs. Split valid ones into seperate lists of files / directories to exclude
for nn in "${@%/}"; do

# get real paths. If path is relative (doesnt start with / or ./ or ~/) assume it is relative to the base search directory (NOT PWD)
case "${nn:0:1}" in
[\~\.\/])
nn="$(realpath "$nn")";
;;
*)
nn="$(realpath "${bdir}/${nn}")";
;;
esac

# ensure path is under base search directory
[[ "$nn" == "${bdir}"\/* ]] || {
printf 'WARNING: "%s" not under base search dir ("%s")\n ignoring "%s"\n\n' "$nn" "${bdir}" "$nn";
continue;
}

# split into files list or directories list
if [[ -f "$nn" ]]; then
efile+=("$nn");
elif [[ -d "$nn" ]]; then
edir+=("$nn");
else
printf 'WARNING: "%s" not found as file or dir.\n Could be a "lack of permissions" issue?\n ignoring "%s"\n\n' "$nn" "$nn";
fi;

done;

# split directories up into nesting levels relative to base search directory
# is base search directory is '/a/b'; then: level 0 is '/a/b', level 1 is '/a/b/_', level 2 is '/a/b/_/_, level 3 is '/a/b/_/_/_' etc.)'
eLevels[0]="${bdir}";
for nn in "${edir[@]%%+([\/\*])}"; do
b="${nn#"${bdir%/}/"}/";
a="${bdir%/}/";
kk=1;
until [[ -z $b ]] || [[ "$a" == "$nn" ]]; do
a+="${b%%/*}/";
b="${b#*/}";
eLevels[$kk]+="${a%\/}"$'\n';
((kk++));
done;
done;

# construct minimal list of files/directories to search that doesnt contain excluded directories and save in array F
# EXAMPLE:
# if the base search directory is '/a/b' and you want to exclude 'a/b/c', 'a/b/d/e', and 'a/b/d/f', this includes:
# everything immediately under '/a/b' except for '/a/b/c' and '/a/b/d' --AND--
# everything immediately under '/a/b/d', except for '/a/b/d/e' and '/a/b/d/f'
mapfile -t F < <(for ((kk=1; kk<${#eLevels[@]}; kk++ )); do
mapfile -t A < <(printf '%s' "${eLevels[$(( $kk - 1 ))]}" | sort -u)
A=("${A[@]}");
for nn in "${A[@]}"; do
mapfile -t B < <(printf '%s' "${eLevels[$kk]}" | grep -F "${nn}" | sort -u)
B=("${B[@]}");

[[ -n "$(printf '%s' "${B[@]//[ \t]/}")" ]] && source /proc/self/fd/0 <<< "find \"${nn}\" -maxdepth 1 -mindepth 1 $(printf '! -path "%s" ' "${B[@]}"; printf '! -wholename "%s/*" ' "${B[@]}")";
done;
done);

# run `find -O3` on the dir list saved in array F, with excluded files (from command line) now being excluded
source /proc/self/fd/0 <<<"find -O3 \"\${F[@]}\" $(printf '! -path "%s" ' "${efile[@]}")";
}

https://redd.it/1abct5q
@r_bash

like grep -A4 but instead of 4 lines go until matched pattern?

Does grep have a way of instead of specifying 4 like grep -A4 to print the lines until it encounters a regex match like ^---? It looks like this is called context line control in the manpage, but that section doesn't give a way to have it variable, the number must be fixed. Does grep have another mechanism that could be used? Right now I've got a python noscript that does this, but I'm very curious about a bash-1-liner. My matches can be printed properly from grep -A2 to grep -A7 to larger like -A33 and there's no way to know what the number is without counting the number of lines until the ^--- is encountered. Is grep capable of doing this on its own or do I need another tool?

https://redd.it/1advlq7
@r_bash

Tool for fast tables in Bash + request for design opinions

I created a table tool for high-performance data access in Bash to support a user interface tool (I'm calling it pwb for Pager with Benefits) I'm finishing up:

Array Table Extension (ate)

The tool is Bash builtin written in C, and as such it can work in the noscript's process space and access elements of the noscript in which it is called, including noscript functions which are sometimes called from the tool.

I would love to find a forum to discuss several design ideas I implemented, but the ate feature about which I am soliciting opinions is one I am also considering for the pwb project is how I create a "handle" with which one accesses the ate features. I think it's pretty developer-friendly, but if I'm mistaken, I might avoid making the same mistake on the new project.

I'll appreciate any comments or insights.

https://redd.it/1adz42r
@r_bash

Readline parsing in command completion

Can someone help me with command completion?

Or perhaps this is more about readline library but still.

BASH_VERSION="4.4.20(1)-release"

I use this simple function to test COMP_* variables during command completion:

complete -F compvars compvars

compvars() { echo >\&2; declare -p ${!COMP_*} >\&2; return 1; }

&#x200B;

And I use arguments like 'name=' and 'name=value' in my noscripts.

For example this works as I expect and COMP_WORDS is easy to use:

&#x200B;

$ compvars a='' b<TAB>

declare -- COMP_CWORD="3"

declare -- COMP_KEY="9"

declare -- COMP_LINE="compvars a='' b"

declare -- COMP_POINT="15"

declare -- COMP_TYPE="33"

declare -- COMP_WORDBREAKS="

\\"'><=;|&(:"

declare -a COMP_WORDS=([0\]="compvars" [1\]="a" [2\]="=''" [3\]="b")

\^C

&#x200B;

But when I use hyphens (to allow spaces in arguments) things get complicated:

&#x200B;

$ compvars a='x' b<TAB>

declare -- COMP_CWORD="3"

declare -- COMP_KEY="9"

declare -- COMP_LINE="compvars a='x' b"

declare -- COMP_POINT="16"

declare -- COMP_TYPE="33"

declare -- COMP_WORDBREAKS="

\\"'><=;|&(:"

declare -a COMP_WORDS=([0\]="compvars" [1\]="a" [2\]="='" [3\]="x' b")

\^C

&#x200B;

Common sense says I should get "b" as separate element in COMP_WORDS also in last completion. Why the last hyphen in COMP_WORDS[3\] doesn't also act as a word break and further split COMP_WORDS[3\] into [3\]="x'" and [4\]="b"?

Is there some solution out there to reassemble COMP_WORDS to overcome cases like this?

&#x200B;

https://redd.it/1ae4rp4
@r_bash

Simple bash noscript help

Hi,

I am hoping I can get some assistance with a simple bash noscript that I will run in a cron

If any file in one particular directory is older than 1 minute, then execute something

I cannot get find to work simply like that

any thoughts?

Thank you !

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