Pipe Arguments To Bash Function

Dec 17, 2016

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This is a trivial example, but is meant to demonstrate how you can pipe arguments to a bash function.

#!/usr/bin/env bash

lowercase()
{
	# Grab input.
	declare input=${1:-$(</dev/stdin)};

	# Use that input to do anything.
	echo "$input" | tr '[:upper:]' '[:lower:]'
}

echo "HELLO there, FRIEND!" | lowercase

Which outputs the following.

hello there, friend!

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