name="John"
echo ${name}
echo ${name/J/j}    #=> "john" (substitution)
echo ${name:0:2}    #=> "Jo" (slicing)
echo ${name::2}     #=> "Jo" (slicing)
echo ${name::-1}    #=> "Joh" (slicing)
echo ${name:(-1)}   #=> "n" (slicing from right)
echo ${name:(-2):1} #=> "h" (slicing from right)
echo ${food:-Cake}  #=> $food or "Cake"

#!/bin/bash

#Installs the Vulkan library and other goodies. Works on Arch and Arch based distros. Needs pacman and makepkg
installVulkan(){

	#Tries installing every linux package in existence
	packages=( vulkan-tools libvulkan-dev vulkan-loader-devel vulkan-validation-layers spirv-tools mesa-vulkan-devel vulkan-validation-layers-devel )
	for package in ${packages[*]}; do
	sudo pacman --noconfirm -S $package
	done
}
installLibraries(){

	#All of these packages don't exist, so we have to download and install the AUR packages

	#packages=( libglfw3-dev glfw-devel libglm glm-devel )

	#for package in ${packages[*]}; do

	# sudo pacman --noconfirm -S $package

	#done
	sudo git clone https://aur.archlinux.org/glfw-git.git /tmp/glfw-git
	sudo chmod 777 /tmp/glfw-git
	cd /tmp/glfw-git
	makepkg -si

	sudo git clone https://aur.archlinux.org/glm-git.git /tmp/glm-git
	sudo chmod 777 /tmp/glm-git
	cd /tmp/glm-git
	makepkg -si
}
installShaderCompiler(){

	#Basically installs glslc
	sudo pacman -S shaderc
}
while true; do
	select bruh in installVulkan installLibraries installShaderCompiler "exit"; do

	$bruh
	done
done

# Three ways of checking if a file exists in a shell script

FILE=/etc/resolv.conf

if test -f "$FILE"; then
    echo "$FILE exists."
fi

if [ -f "$FILE" ]; then
    echo "$FILE exists."
fi

if [[ -f "$FILE" ]]; then
    echo "$FILE exists."
fi

#!/bin/bash


# Recursively find all .svelte files in the current directory and its subdirectories
find . -type f -name "*.svelte" -o -name "*.html" -o -name "*.htm" | while read file; do
        # Replace all h1 tags with the specified format
        sed -i 's/<h1>\(.*\)<\/h1>/<h1 id="\1">\1<\/h1>/g' "$file"
        # Replace all h2 tags with the specified format
        sed -i 's/<h2>\(.*\)<\/h2>/<h2 id="\1">\1<\/h2>/g' "$file"
        # Remove whitespace from the id attribute value
        for i in {0..10} ; do
                sed -i 's/\(id="[^"]*\)\W\([^"]*"\)/\1\2/g' "$file"
        done
done

#pinger.sh by Leif Messinger

#./pinger.sh [ADDRESS] to search

#./pinger.sh [ADDRESS] & to search in the background

#https://serverfault.com/a/42382
ping_cancelled=false # Keep track of whether the loop was cancelled, or succeeded
until ping -c1 "$1" >/dev/null 2>&1; do :; done & # The "&" backgrounds it
trap "kill $!; ping_cancelled=true" SIGINT
wait $! # Wait for the loop to exit, one way or another
trap - SIGINT # Remove the trap, now we're done with it
if [ "$ping_cancelled" == true ] #https://stackoverflow.com/a/21210966/10141528
then
	printf "The pinger for $1 just closed bro.\n"
else
	printf "$1 IS UP BROOO\a\n"
fi

for region in `aws ec2 describe-regions --output text | cut -f4`
do
     echo -e "\nListing Instances in region:'$region'..."
     aws ec2 describe-instances --query 'Reservations[*].Instances[*].{Instance:InstanceId,Subnet:SubnetId}' --region $region
done
#This script is to be used with any AWS CLI configured environment, it will list any EC2 instances and their associated subnet network ID's in JSON format