What's the simplest way to remove lines from one file matched with lines from another file? For example, if I have the following files:
1,firstname.lastname@example.org,somehash1 2,email@example.com,somehash2 3,firstname.lastname@example.org,somehash3
As a result I'd like to have file3.csv:
What's the fastest way to solve this task? These files are a few GB in size.