Running sed on MacOS

Introduction

When running sed on a Macbook I get the follwoing error

sed -i "s/true/false/g" myfile

Warning

sed: 1: "Library/Group Container ...": invalid command code L

Solution

The -i option expects an extension argument so the command above is actually parsed as the extension argument and the file path is interpreted as the command code.

Adding the -e argument explicitly and giving '' as argument to -i:

sed -i '' -e "s/true/false/g" myfile