# 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

touch /tmp/login1.txt /tmp/login2.txt
while [ true ]
do
	who | gawk '{ print $1 }' > /tmp/login2.txt
	comm -13 /tmp/login1.txt /tmp/login2.txt
	#Just a bit easier to read
	#diff /tmp/login1.txt /tmp/login2.txt
	cat /tmp/login2.txt > /tmp/login1.txt
	sleep 1
done

echo -e ${PATH//:/\\n} | awk '{print length, $0}' | sort -n | cut -f2- -d' '

#!/bin/bash
# Turns 4 spaces into tabs.
# Mostly stolen from AI
# Define the directory to process
DIRECTORY=$1
TabCount=${2:-'4'}    #Defaults to 4

# Check if directory is specified
if [ -z "$DIRECTORY" ]; then
    echo "Error: Directory not specified."
    exit 1
fi

# Check if directory exists
if [ ! -d "$DIRECTORY" ]; then
    echo "Error: Directory does not exist."
    exit 1
fi

# Find all files in directory and subdirectories
FILES=$(find "$DIRECTORY" -type f)

# Loop through each file and unexpand it
for FILE in $FILES; do
	unexpand -t "$TabCount" "$FILE" > "$FILE.tmp"
	mv "$FILE.tmp" "$FILE"
done

echo "Done!"

#!/bin/sh

BAT_LOW=15
BAT_CRITICAL=5

if [ "$1" = "--help" ]
then
    printf "
    Usage:
    \tbattery_check.sh warning%% hibernate%%

    Description:
    \tA script for notifying the user via dunst and logging when
    \tthe battery is low and the system is going to hibernate.
    \tCan be supplied arguments for the battery low warning and
    \thibernation percentage thresholds as the first and second arguments.

    \t Default behavior is to warn at 15% and hibernate at 5%."
    exit
fi

if [[ -n "$1" && -n "$2" && $1 -gt $2 ]]
then
    BAT_LOW=$1
    BAT_CRITICAL=$2
fi

acpi -b | awk -F'[,:%]' '{print $2, $3}' | {

    read -r status capacity
    echo Low threshold: $BAT_LOW, Hibernate threshold: $BAT_CRITICAL
    echo Status: $status, Capacity: $capacity

    if [ "$status" = Discharging -a "$capacity" -le $BAT_CRITICAL ]; then
        echo Battery critical threshold.
        dunstify -u critical "Critical battery threshold, hibernating..."
        logger "Critical battery threshold, hibernating..."
        sleep .5
        systemctl hibernate
        exit
    fi

    if [ "$status" = Discharging -a "$capacity" -le $BAT_LOW ]; then
        echo Battery low threshold.
        dunstify -u critical 'Battery low! System will hibernate at 5%.'
        logger 'Battery low! System will hibernate at 5%.'
        sleep .5
        light -S 15
        exit
    fi
}

#!/bin/bash
#Takes command line arguments and pulls the header files.
#Good for checking if the function you want is in the header or not.
#cppToStdout.sh "time.h"
while [ "$1" != "" ]; do
	echo "#include<$1>" | g++ -x c++ -E -
	shift
done