bash command overwritten by later command

Under what conditions can a bash command be overwritten by a later command?

https://redd.it/1ajd4je
@r_bash

LLUVIA DE IDEAS PARA UN SCRIPT Y CONTRIBUYENTES

Hola soy un novato en bash y me gustaria tener un compañero o gente que quiera contribuir a mi reposito de github (https://github.com/Arbolencio/NetPurge) discord:arbolencio

https://redd.it/1ajit4a
@r_bash

Bash noscript that turns on the led on the mute key

I have a working bash noscript, but so far I have not implemented a trigger for it. It also requires sudo privileges which I'm afraid may interfere. How do I trigger this noscript when I press a specific function key (certainly not a bash noscripting question, sorry)? Currently it's in a .noscripts folder in $HOME. Here's the noscript:

echo `amixer get Capture | tail -n 2 | grep -q '\[on\]'; echo $?` | sudo tee /sys/class/leds/platform\:\:micmute/brightness

I know this is quite a small noscript but any suggestions on making the noscript is appreciated.

Thank you.

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

scp-turbo

Speeding up multiple files copy over SSH, uses scp syntax, e.g. scp-turbo.sh myremote:/etc/apache2 /backups/apacheconf. (assuming myremote is an alias you have configured in ~/.ssh/config)

This is a bash wrapper for running something like tar -czf - /etc/apache2 | ssh myremote "tar -xzf - -C /backups/apacheconf".

#!/usr/bin/env bash

# uses scp syntax e.g.:
#
# REMOTE -> LOCAL
# scp-turbo.sh myremote:/etc/apache2 /tmp/mylocal/dir
#
# LOCAL -> REMOTE
# scp-turbo.sh /tmp/mylocal/dir myremote:/home/user32/ 

if [[ $# -eq 0 ]]; then
  printf "USAGE:\n\t${0##*/} <source> <destination>\n\n"
  echo "NOTE: Source and destination can be in the format host:path or just path"
  exit 1
fi

source=$1
dest=$2

if [[ $source == *:* ]]; then
  source_host=${source%%:*}
  source_dir=${source#*:}
else
  source_host=""
  source_dir=$source
fi

if [[ $dest == *:* ]]; then
  dest_host=${dest%%:*}
  dest_dir=${dest#*:}
else
  dest_host=""
  dest_dir=$dest
fi

echo SOURCE_HOST: "$source_host"
echo SOURCE_DIR: "$source_dir"
echo 
echo DEST_HOST: "$dest_host"
echo DEST_DIR: "$dest_dir"

read -p "Press any key to start copying..." -n 1 -s

# create target dir if not exist
if [[ ! -d "$dest_dir" ]]; then
  mkdir -p "$dest_dir"
fi

# REMOTE -> LOCAL
if [[ -z "$dest_host" ]] && [[ -n "$source_host" ]] && [[ -n "$source_dir" ]] && [[ -n "$dest_dir" ]]; then
  ssh "$source_host" tar --ignore-failed-read -cvf - -C "$source_dir" . | tar xvf - -C "${dest_dir}"
  echo "Done!"
  exit 0
fi

# LOCAL -> REMOTE
if [[ -z "$source_host" ]] &&  [[ -n "$source_dir" ]] && [[ -n "$dest_host" ]] && [[ -n "$dest_dir" ]]; then
  
  ssh "$dest_host" mkdir -p "$dest_dir"
  
  tar -cvf - -C "${source_dir}" .  | ssh "$dest_host" "tar -xvf - -C $dest_dir" 
  echo "Done!"
  exit 0
fi

github gist

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

Replace output with next one while running noscript

I have this command that runs a noscript containing functions with wget

$SUDOCOMMAND ./$arg 2>&1 | grep -v ": "

This is a part of the long output I can see (from 1 to 100%)

...
152250K .......... .......... .......... .......... .......... 75% 8,15M 6s
152300K .......... .......... .......... .......... .......... 75% 8,53M 6s
152350K .......... .......... .......... .......... .......... 75% 9,76M 6s
152400K .......... .......... .......... .......... .......... 75% 8,49M 6s
152450K .......... .......... .......... .......... .......... 75% 8,46M 6s
152500K .......... .......... .......... .......... .......... 76% 6,30M 6s
152550K .......... .......... .......... .......... .......... 76% 8,51M 6s
152600K .......... .......... .......... .......... .......... 76% 8,11M 6s
152650K .......... .......... .......... .......... .......... 76% 8,14M 6s
152700K .......... .......... .......... .......... .......... 76% 8,51M 6s
152750K .......... .......... .......... .......... .......... 76% 8,85M 6s
152800K .......... .......... .......... .......... .......... 76% 8,52M 6s
152850K .......... .......... .......... .......... .......... 76% 8,46M 6s
152900K .......... .......... .......... .......... .......... 76% 6,72M 6s
152950K .......... .......... .......... .......... .......... 76% 8,94M 6s
153000K .......... .......... .......... .......... .......... 76% 8,14M 6s
153050K .......... .......... .......... .......... .......... 76% 8,48M 6s
153100K .......... .......... .......... .......... .......... 76% 8,88M 6s
153150K .......... .......... .......... .......... .......... 76% 6,09M 6s
153200K .......... .......... .......... .......... .......... 76% 8,49M 6s
...

How can I overwrite each line with the next one (until it reaches 100%) to have a smaller output (so I can see percentage and countdown on the right increasing/decreasing)?

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

Online environment for online demo of bash projects

I'm making a text based adventure game in bash and I'm looking for a way to set up a shareable environment with my git repo cloned and set up to play the game in the browser.

I only need a hand full of shell tools like cat, grep, ls and such.

I tried replit, but idk if I did it wrong or what, but the shared replit doesn't show the bash console so that rules it out.

I've been searching for about an hour now and the only option seems to be to setup xterm.js with some kind of backed that runs bash code in a server.

I'm sure I've seen other repos that had an in-browser demo of their noscripts, but I can't remember what they used.

Is there a (preferably free) service or tool or website that I can use for this purpose?

PS: I could probably redirect people to jslinux but all my pretty boxes break and look like a*s there.

https://redd.it/1ak2sum
@r_bash

Pass argument to bash noscript to vary end of a path?

I have a noscript that will do something with a path like:

Launch /home/joe/file1

Launch /home/joe/file2

You'd basically pass the "file2" as an argument to the noscript and it fills in the file1 or file2 or whatever depending on the argument you supply to the noscript.

So typing "somenoscript.sh file1"

Would build the line

Launch /home/joe/file1

If I typed "somenoscript.sh foo" it'll make:

Launch /home/joe/foo


Thanks

https://redd.it/1ak5q8y
@r_bash

Test if variable is a float?

Hi

I test if a variable contains an integer like this

[ $var == ?(-)+([[:digit:]) ]]


Is there a similar test to see if it is a float, say 1.23 or -1.23

Thanks

​

https://redd.it/1ak9a1l
@r_bash

Any flaws in this noscript that could be potentially bad?

#!/bin/bash

# Check if three arguments are provided
if "$#" -ne 3 ; then
echo "Usage: $0 <begtime> <endtime> <logfilegzipped>"
exit 1
fi

beg=$1
end=$2
logfilegzipped=$3
function nongzipped() {
LCALL=C awk -v beg="$beg" -v end="$end" '
match($0, /0-20-9:0-50-9:0-50-9/) {
t = substr($0, RSTART, 8)
if (t >= end) selected = 0
else if (t >= beg) selected = 1
}
selected' "$logfilegzipped" #ignore the name lol
}

function gzipped() {
zcat "$logfilegzipped" | LCALL=C awk -v beg="$beg" -v end="$end" '
match($0, /[0-2][0-9]:[0-5][0-9]:[0-5][0-9]/) {
t = substr($0, RSTART, 8)
if (t >= end) selected = 0
else if (t >= beg) selected = 1
}
selected'
}
if [[ "$logfilegzipped" == *.gz ]]; then
gzipped
else
nongzipped
fi

I just modified this noscript that I wrote few months ago to accomodate both cases of gzipped and non gzipped log files. Any flaws with this you can notice. This works on my machine.

Any ways to make this better? Please don't post solutions. I'd have asked chatgpt but I like the journey in learning rather than getting answers quickly. Only correct me if there is serious flaw in this.

https://redd.it/1akbuj9
@r_bash

Any better solutions than this one?

print_progress(){
    local progress_msg="${1}"; shift

    local separator_string=
    for ((i = 0; i < COLUMNS; i = i + 1)); do
        separator_string+='='
    done
    printf '\n%s\n%s\n%s\n' \
        "${separator_string}" \
        "${progress_msg}" \
        "${separator_string}"
}
print_progress 'Currently doing blablabla...'

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

Help with noscript - creating a 'simple' compose file on remote server via ssh

I run a bash noscript on my local pc. Its configures a remote server by ssh, adding users, installing docker etc. Theres a part in it that writes and then runs a traefik compose file but there is a line in it that bash doent seem to like:

\- "traefik.http.routers.api.rule=Host(`website.com`)"

It ends up writing the line:

\- "traefik.http.routers.api.rule=Host()"

This causes the container to fail.

&#x200B;

Ive even tried (unsuccessfully) writing the file with commands such as:

printf '%s\\n' " - traefik.http.routers.api.rule=Host('website.com')"

&#x200B;

How do i get round this problem. GPT is looping on me and getting nowhere. Part of my noscript:

&#x200B;

su - bob -c "

\# Create and write to the file

cat > docker-compose_traefik.yml << 'EOF'

version: "3.3"

&#x200B;

services:

traefik:

image: traefik:v3.0

restart: always

container_name: traefik

ports:

\- "80:80"

\- "8080:8080"

\- "443:443"

command:

\- --api.insecure=true

\- --api.dashboard=true

\- --api.debug=true

\- --log.level=DEBUG

\- --providers.docker=true

\- --providers.docker.exposedbydefault=false

\- --providers.file.filename=/dynamic.yaml

\- --providers.docker.network=web

\- --entrypoints.web.address=:80

volumes:

\- /var/run/docker.sock:/var/run/docker.sock

\- ./dynamic.yaml:/dynamic.yaml

networks:

\- web

labels:

\- "traefik.enable=true"

\- "traefik.http.routers.api.rule=Host(`website.com`)"

\- "traefik.http.routers.api.service=api@internal" access

&#x200B;

networks:

web:

external: true

EOF

&#x200B;

https://redd.it/1akyrk4
@r_bash

Code review request

I tested the program on 5 machines running on matic 23.10 and cant find any issues. Would like to know if there are any issues with the code. As code is broken down into many functions i cant upload snippets here.
I would like reviewers to point to memory_init function which is an odd ball in the whole hierarchy.
Here is the link.

https://github.com/ioprojecton/CPU-Y

Thanks.

https://redd.it/1al1lw9
@r_bash

Issue with a simple Bash Script for adding an iRule to a list of Virtual Servers.

Hello Community, 

I am quite new to Bash noscripting. Though I know the platform I intend the noscript to run on is not relevant to this sub, I would appreciate if you could at least elevate my concern that the problem I am encountering is with my Bash noscript itself and not the environment I'm running it on.

I am having an issue with a bash noscript for an F5 BIG-IP Load Balancer which is intended to:

1. Take as input a .txt file named "vs_list.txt" containing a list of Virtual Server Names, each on a separate row.

2. Prompt the user for the name of the iRule that needs to be added to the Virtual Servers.

3. Iterate over the VS Names from the input list and retreives the partition in which each VS resides (building on F5 Support Solution K59493724: How to get details of the virtual servers in all partitions via TMSH? (https://my.f5.com/manage/s/article/K59493724))

4. Checks for and retrevies the iRules which are currently configured for the given VS# Adds the new iRule to the given VS and coserves pre-existing iRules if any. 


When running the noscript I am only hitting the outermost 'else' statement for being unable to find the partition and VS name.



#!/bin/bash

# Prompt the user for the iRule name and read it into the 'new' variable
echo "Please enter the iRule name:"
read new

noneRules='rules none'

while IFS= read -r vsname; do
# Retrieve the partition and virtual server name
fullvsinfo=$(tmsh -c "cd /; list ltm virtual recursive" | grep "$vsname" | grep -m1 "^ltm virtual")
echo "Full VS Info Debug: $fullvsinfo"

# Extract the partition and virtual server name from the retrieved information
if [ $full_vs_info =~ ltm\ virtual\ (.+)/(.+) ]; then
partition="${BASHREMATCH[1]}"
vsname="${BASHREMATCH[2]}"

# Format the tmsh command to include the partition
rule=$(tmsh list ltm virtual /$partition/$vsname rules | egrep -v "\{|\}" | xargs)

if [ "$rule" == "$noneRules" ]; then
tmsh modify ltm virtual /$partition/$vsname rules { $new }
echo "iRule $new was added to $vsname in partition $partition"
else#
tmsh modify ltm virtual /$partition/$vsname rules { $rule $new }
echo "iRules $rule were conserved and added $new to $vsname in partition $partition"
fi
else
echo "Could not find partition and virtual server name for $vsname"
fi
done < /shared/tmp/testlist.txt

tmsh save sys config

As far as I was able to troubleshoot, the problem I am encountering appears to be with line 11 of my noscript where I attempt to assign the string "ltm virtual SomePartition/VS_Example.com {" to the "full_vs_info" variable using:

full_vs_info=$(tmsh -c "cd /; list ltm virtual recursive" | grep "$vs_name" | grep -m1 "\^ltm virtual")

When I run the tmsh command [tmsh -c "cd /; list ltm virtual recursive" | grep "VS_Example.com" | grep -m1 "\^ltm virtual"\] on its own, from the F5's Bash shell, I am getting the output I expect:

"ltm virtual SomePartition/VS_Example.com {"

However, when I run the noscript with the debug echo , it only outputs "Full VS Info Debug:", and ends the noscript with "Could not find partition and virtual server name for $vs_name" and a sys config save.

If at all relevant, I am attempting to run this on a BIG-IP, version (https://15.1.10.2), build 0.44.2. 

All feedback and criticism is highly appreciated! Thanks in advance!

https://redd.it/1al6h61
@r_bash

bash against smoking
https://redd.it/1amdhxj
@r_bash

Responsive image gallery in three lines of bash

Three lines of bash to generate a responsive HTML image gallery — motivated by having to spend way too much time on getting /r/immich and /r/photoprism to do what I wanted them to do... both are awesome projects btw.

>❗️NOTE: on MacOS this requires the GNU flavour of find — use brew install findutils and replace in the noscript find with gfind.

echo '<html><head><style>img {max-width: 321px; height: auto; display: table-cell;} body>div {display: grid; grid-template-columns: repeat(auto-fill, minmax(321px, 1fr)); gap: 5px;}</style></head><body><div>' > gallery.html
find -type f ! -name '.*' -a -iregex '.*\.\(jpg\|jpeg\|png\|noscript\|bmp\|webp\|gif\)' -printf '<a href="%P" target="blank" noscript="%P size: %s bytes; created: %c"><img src="%P" loading="lazy"></a>\n' >> gallery.html
echo '</div></body></html>' >> gallery.html

(the only reason I did not extract gallery.html to a variable was to keep it to 3 lines)

https://redd.it/1amkg1n
@r_bash

What do you call the '-' when used to specify options (like set -x)?



View Poll

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

Invoke bash noscript in remote server

I'm running a noscript from my jump host to copy a noscript to client servers. From that copied noscript will run on the client server and check for a specific agent is installed or not. If not it will install through that noscript. But before installation happen I want to raise a standard change servicenow.

Standard change raising noscript also in the jumphost. That only can be run from the jumphost.

So I want to know how can we invoke standard change raising noscript with parsing some information to that from the client machine,

https://redd.it/1amqbf8
@r_bash

Teleport it
https://redd.it/1anzmda
@r_bash

Dynamic FFmpeg build noscript

This builds the latest stable release version series 6 of FFmpeg with additional codecs included.

This will dynamically find the latest source code for each codec and update them accordingly.

I am slowly working on a GNU version of this noscript that will allow the user to specify a GNU all build so check back over time.

As always I hope some of you guys find this useful.

Cheers

&#x200B;

Lit of codecs available

GitHub Script

https://redd.it/1ao2csh
@r_bash

Shell noscript that can add bookmarked directories and cd into them directly (+video)

Hi all. I was getting tired of writing long cd commands to get to specific directories in the terminal. I found there were some programs/tricks for this (like CDPATH) but none of them worked for me. Hence, I made a small shell noscript that can add/delete/navigate bookmarked directories. Thank you!

You can watch a 2 minute demo here: Loom video

Or view the source code here: https://github.com/TimoKats/CDBookmark/

https://redd.it/1ao5lob
@r_bash

GREP - Practical Guide 🚀

Last month, I discovered one of the best terminal commands. And wrote a blog about it here - https://www.priya.today/blogs/grep
Can you share some useful tips and tricks?
I would greatly appreciate your feedback.

https://redd.it/1ao6dfz
@r_bash