Exploring the if then else

• If the else

if command
then
    commands
else
    commands
fi

• if then elif

if command
then
    commands
elif command2
then
    commands
fi

Functions

• A reusable block of code is called as function
• Lets write a reusable code to get the distribution

#!/bin/bash


# function definition to get distribution
get_distribution() {
    distribution=""
    # Check if /etc/os-release  file exists
    if [ -r /etc/os-release ]; then
        distribution="$(. /etc/os-release && echo "$ID")"
    fi
    echo $distribution

}

# usage
echo $(get_distribution)

• refer here for function