Updates bash-scripting.md

# Bash-scripting

### Variables

```bash

# There can't be any space between the variable name and the equal sign. It has to be varname=command

battery_time=$(cat /sys/class/power_supply/BAT0/capacity)

# The variables cna then be used like this

echo "$battery_time"

```

## Iterate over a file

This script will iterate over a file and echo out every single line:

`$1` here represent the first argument.

```bash

if [ "$1" == "" ]; then

    echo "This happens"

fi

fi

```

## Command line arguments

Command line arguments are represented like this

$1

```

This is the first command line argument.

## Daemonize an execution

done

```

## Use the output of command

It has happened to me several times that I want to input the output of a command into a new command, for example:

```