Only download if file doesn't exist

Wrote this Bash noscript to download a file and place it in a folder however it's re-downloading every time it's run. I'd like for the download to only occur if the file does not already exist.

#!/bin/bash
# Download files from Github repo to /tmp/appfolder

URLDOWNLOAD1="https://raw.githubusercontent.com/Work/Repo/main/appfolder/logo.png";
TEMPDIR="appfolder";

FILENAME="$(basename $URLDOWNLOAD1)";
DOWNLOADFILE="/tmp/$TEMPDIR/$FILENAME";

if ! -d "/tmp/$TEMPDIR" ; then
mkdir -p "/tmp/$TEMPDIR";
fi;

curl -L --silent -o "$DOWNLOADFILE" "$URLDOWNLOAD1";

if -e $DOWNLOADFILE ; then
echo "$DOWNLOADFILE - Success";
else
echo "logo.png Download failed";
fi

Any assistance would be greatly appreciated!

https://redd.it/13of1p1
@r_bash

findpick - General purpose file picker combining "find" command with a fuzzy finder
https://github.com/thingsiplay/findpick

https://redd.it/13oj98j
@r_bash

Pipelight - Automation with Typenoscript{Bash} 🤌

I needed something to glue commands together but I prefer using javanoscript syntax over bash conditionals, loops and functions (yes i am evil 😈)

It has matured over the years, has been roasted, improved, refactored, and I think it has become stable enough to share it once again!

It's merely bash wrapped with typenoscript , with extra automation super powers 🦸

Documentation still improving: https://pipelight.dev/

I leave this here for the ones who need this kind of tool and hope you will find it usefull 😄

https://redd.it/13olxdi
@r_bash

Protecting SSHD's Listening Port with Port Knocking (or better)

Hi all

Whenever I set up a Linux box/VPS,
the first thing I do is change SSHD's Listening Port to something different than the default port.

I would like to add another protection to it, and start using Port Knocking,
so the port would appear Closed/NotListening to anyone,
except me, when I want to connect.

Can you please tell me what you recommend to use?

And also:
Is there something more advanced than Port Knocking that I should check,
for protecting the listening port?


Thank you very much

https://redd.it/13onqb7
@r_bash

print $0 giving me unexpected result

Good afternoon, I am relatively new to using awk commands but I am running into a small issue with a output that involves $0.

I am reading in trade_data.csv.small:

sym,price,size,side,market,time,id

MDT,72.34000000,100,Short,NASDAQ,10:00:00.146882,1180355

MDT,72.35000000,125,Short,NASDAQ,10:00:00.165655,1180537

​

This is my awk line:

awk -F "[,\]" 'NR>1 {if ($3 == 100) print $0, " | 100 "; else print $0, " | not 100 | "}' trade_data.csv.small

​

The output is:

| 100 4000000,100,Short,NASDAQ,10:00:00.146882,1180355

| not 100 | 0,125,Short,NASDAQ,10:00:00.165655,1180537

​

I thought that the output would be something like:

MDT,72.34000000,100,Short,NASDAQ,10:00:00.146882,1180355 | 100

MDT,72.35000000,125,Short,NASDAQ,10:00:00.165655,1180537 | not 100

​

What am I doing wrong here?

Thank you in advance for your insight(s).

https://redd.it/13oxjfs
@r_bash

HAVING ERROR IN FIRST CODE

Hello everyone so I started learning bash today and I am making a basic math calculator thorugh my VMware kali terminal. I dont know why but I am getting this error of line 35 error: syntax error near unexpected token ' echo "result: $result" '...Can anyone help me out? (Attaching my code below)
ALSO in my code image if I remove single quotes it still shows error

https://preview.redd.it/akbma2u5kf1b1.png?width=412&format=png&auto=webp&v=enabled&s=76a7ac94a05cc9e0e11c8956e5358b43e516cd21

https://redd.it/13ozru9
@r_bash

How to create Bash noscript that first checks if it's already running?

I've got an rsync noscript that is run daily, but often there is so much to back up it fires up another job when I want the original job to complete first.

I know a process id check can be used for this — can someone please direct me towards a tutorial or method on how to do that?

TIA!

https://redd.it/13p4osw
@r_bash

Compare the differences between dirs and sync

I have two directories A (local) and B (Remote/SFTP). I would like to somehow sync them based to A.

I cant really rsync because A dir has plaintext files and B has encrypted files(GPG).

Example:

Local dir contains: A.txt, B.txt, D.txt, F.txt, G.txt

Remote dir contains: A.txt.gpg, B.txt.gpg, C.txt.gpg, D.txt.gpg, E.txt.gpg, F.txt.gpg

The result I need is remote dir to be like A.txt.gpg, B.txt.gpg, D.txt.gpg, F.txt.gpg, G.txt.gpg

Hence, the file G.txt will be transfer over and files C & F will be deleted from remote dir

P.S I have the functions ready to basebane fies, encrypt them, rsync them.

​

​

My question is how to compare the differences and run my functions accordingly?

What is coming to my mind is to create a array for each dir and compare but Im sure there is smarter and cleaner way than that. Any thoughts?

https://redd.it/13phrj7
@r_bash

save - Capture and reuse output of command (Bash function)
https://gist.github.com/thingsiplay/612d2482b8747cf20e6bf4756d43eed4

https://redd.it/13pl4xs
@r_bash

A bash noscript for converting security camera recordings in .media or similar format to .mp4/.mkv

Received a video recording from a friend for checking a burglary event. Looking at the sdcard contents, there seems to be many folders with names like 1645645354 and contents with `.media` files. Turns out the file names are unix epoch and the `.media` files can be converted using `ffmpeg`. Wrote small noscript and tested on few thousand files. It might be useful for someone else:

https://github.com/IbrahimTanyalcin/camToMP4

MIT License, logo and comments by chatGPT

https://redd.it/13pm9x6
@r_bash

solaris 10 cron failed command substitution.

0,20,40 * * * bash -c -l /usr/local/monitors/lp_mon2

\#!/bin/bash



\#grab oldest file from queue

stuff=\`ls -1 /var/spool/lp/requests/localhost/ | /usr/bin/head -1\`

\#pull printer name from lp requests (first line in file)

puff=\`cat $stuff | /usr/bin/head -1 | sed -e 's/-.*//' -e 's/$/ is having issues printing from /'\`



if [ "$(ls -A /var/spool/lp/requests/localhost/)" ]

then

echo $puff | /usr/ucb/mail foo@bar.com
else

echo lp queue is empty | /usr/ucb/mail foo@bar.com

fi

Also tried:

stuff="(ls -1 /var/spool/lp/requests/localhost/ | /usr/bin/head -1)"


puff="$(cat $stuff | /usr/bin/head -1 | sed -e 's/-.*//' -e 's/$/ is having issues printing

Suggestions??

https://redd.it/13pq6d3
@r_bash

how to prevent this variable form becoming equal to when directory is empty

list=$(for f in "$dir"/\ ; do printf '%s\\n' "$(basename $f)" ; done )

works as expected when the directory is not empty but when it's empty, it becomes equal to * and I want it to become an empty string if the directory is empty

https://redd.it/13q28rv
@r_bash

the case for bash
https://www.neversaw.us/2021/04/02/the-case-for-bash/

https://redd.it/13ql14n
@r_bash

Simple file path opening code

I’m as new as you can get to using bash and was trying to make a little code to make some of my work tasks easier. I’ve just been saving a .txt file as .bat and double clicking when I need to use it.

I figured out how to use explorer to open the file path I want, but now I want it to be a little smarter. Say I have the file path:

T:\Files\Reports

I figured how to open it using “explorer” but now I want to add the month after and have it change to the current month accordingly. For example, this month would be:

explorer T:\Files\Reports\04

I have found multiple things online on how to get current date and how to concatenate strings, but “explorer” doesn’t seem to accept a variable as a useable path. I’m not sure about many of the rules of bash code and all it’s intricacies, so I was hoping someone here could help me. Thanks!!

https://redd.it/13qoinl
@r_bash

Script not working like we had envisioned it working

I've been working with ChatGPT to create a noscript that iterates through my entire music library, looking for filenames that are like "<##> - <Artist> - <Title>", and renaming them as "<##> <Title>". I still need to add a couple conventions, like "<##>. <Artist> - <Title>" and such, but the problem is that it's currently not doing what it should, leaving filenames as "<##> - <Title>" or just leaving the filename completely unchanged. It's also supposed to add a leading zero to the track number in the filename if it's 's a single digit. It's not doing that, either. We've been working at this for a couple hours trying to figure out why it's not doing the thing. Here's the noscript. Edit: Forgot to "ask a question", so, Can you help me? Edit 2: Oh, by the way, I know the music_library path is set to '/path/to/music/library' I do have it set properly on my system. Edit 3: left out a bit of what it's supposed to do.

https://redd.it/13qq0wr
@r_bash

Two-Way File <-> FileList Check

Hello, this bash noscript will loop through lines of files from FileList.txt and check if a directory contains such file... Now I want to do it the other way, loop through a directory and check if filename exists in the FileList.txt . How do I do it? Files may contain special characters...

#!/usr/bin/env bash
#Check Files in list from file exist or doesn't exist in directory.

if $# -eq 0 || $# -eq 1
then
echo "You must pass the path to file with the list and the path to directory to check files. \nsh check-file-exist-from-list.sh path/to/file path/to/directory"
exit 1
fi

while read -r file; do
if -e "$2/$file" ; then
echo "$file exists in $2"
else
echo "$file doesn't exist in $2"
fi
done < "$1"

https://redd.it/13qwd06
@r_bash

I have a weird Syntax error near unexpected token ")"

I can't remember what I was trying to do, I think I modified something in JAVA_HOME and since then I broke everything.

Brew doesn't work anymore, the custom color scheme I had for the terminal is gone and I always get this error

&#x200B;

https://preview.redd.it/grw8emfl8u1b1.png?width=1884&format=png&auto=webp&v=enabled&s=16b1fae9a35417301bcba8c9f2301b4cdc9672bd

It says there is an unexpected token ) in line 1, but there's none there

&#x200B;

https://preview.redd.it/128o2qaq8u1b1.png?width=1972&format=png&auto=webp&v=enabled&s=7da6270a482d9077cae6ec3aee0875405ba46b1e

As you can see here. I am a complete noob with bash and I had a friend set up brew and other neat tools for me, I tried to find a solution myself for days, but I can't for the life of me understand what is going on.. can someone help me?

https://redd.it/13qwmpo
@r_bash

Calculate space savings from deduplicating with hardlinks (using find, sort/uniq, and awk)
https://gist.github.com/Sidneys1/d726c2a59f2dcb1be9dfce2dfae0a042

https://redd.it/13r0hji
@r_bash

trying to number a variable. 1. causing an error 2. I don't know if this is the best way to do it

evalWithNum(){
i=1
listWithNum=$(while read line
do
printf '%d. %s' "$i" ""$line""
i=$((i+1))
done < "$list"
)
unset i
}

"$list" is

a

b

c

&#x200B;

the error is

cannot open a
b
c: No such file

https://redd.it/13r29fw
@r_bash

while loop skips steps?

I have a text file that has variable data a space then a path to a file.

DATA ./path/to/file

This is repeated several dozen times. I am trying to convert mkv files to mp4.


I then have the following code:


#!/bin/bash

if [ -z $1 ]
then
echo "Usage:"
echo
echo '$ ./mkv2mp4.sh "Title.of.TV.Show" file.list "1080p.h264"'
echo
echo "Where file.list is a space seperated file format as:"
echo
echo "S01E01 ./path/to/episode1.mkv"
exit
else
filelist=$2
extras=$3
shownoscript=$1
declare -a array
fi

while read -r mkvfile
do
array=( $mkvfile )
echo "Read from: ${array1}" >> mkv2mp4.log
echo "Write to: $shownoscript.${array0}.$extras.mp4" >> mkv2mp4.log
echo "Read from: ${array1}"
echo "Write to: $shownoscript.${array0}.$extras.mp4"
echo "Start: $( date )" >> mkv2mp4.log
#sleep 1s
ffmpeg -i "${array1}" -c:v copy -c:a aac "$shownoscript.${array0}.$extras.mp4"
echo "Done..."
sleep 1s
echo "Finish: $( date )" >> mkv2mp4.log
done < $filelist


If I run it, it gets to the end of the first video, then it skips almost the entire list and proceeds with one of the last videos in the list. If I comment out the ffmpeg line, it doesn't skip anything.


Any help would be appreciated.

https://redd.it/13rng0x
@r_bash

Detecting Chinese characters using grep

I'm writing a noscript that automatically translates filenames and renames them in English. The languages I deal with on a daily basis are Arabic, Russian, and Chinese. Arabic and Russian are easy enough:

orig_name="$1"
echo "$orig_name" | grep -q "[ابتثجحخدذرزسشصضطظعغفقكلمنهويأءؤ]" && detected_lang=ar
echo "$orig_name" | grep -qi "[йцукенгшщзхъфывапролджэячсмитьбю]" && detected_lang=ru

I can see that this is a very brute-force method and better methods surely exist, but it works, and I know of no other. However, Chinese is a problem: I can't list tens of thousands of characters inside grep unless I want the noscript to be massive. How do I do this?

https://redd.it/13rqfjd
@r_bash