Global vs Local Variables - Bash Scripting

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#bash #sonarsystems #snrsys

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[parkerhemphill]

This video is totally wrong. num2 is returning null because it is being echoed BEFORE the function is being called that defines it. The true way to define a local variable inside a function is with local:

tl;dr FTFY

num1=10

Hello(){
local num2=9
echo "Inside of function num1: ${num1}"
echo "Inside of function num2: ${num2}"
}

#This isn't a local variable and will work inside and outside function
echo "Outside of function num1: ${num1}"

#This is null because it's called before the variable "num2" is defined
echo "Outside of function num2: ${num2}"

#Now call the function and see both variables expressed
Hello

#This will still return a value since it isn't local to the function
echo "Outside of function num1: ${num1}"

#This will return null since it is a local variable and only set inside the function
echo "Outside of function num2: ${num2}"