SKIP grep, use AWK

July 3, 2017

Over the years, I’ve seen many people use this pattern (filter-map):

$ [data is generated] | grep something | awk '{print $2}'

but it can be shortened to:

$ [data is generated] | awk '/something/ {print $2}'

You (probably) don’t need grep

Following this logic, you can replace a simple grep with:

$ [data is generated] | awk '/something/'

This will implicitly print lines that match the regular expression.

If feel lost, I’ve got an illuminating series of posts about awk for you.

Why would I do this?

I can think of 4 reasons:

But “grep -v” is OK…

It’s possible to emulate grep -v with awk, but it’s not a good idea:

$ [data is generated] | awk '/something/ {next} 1'

UPDATE:

Many people have pointed out that “grep -v” can be done more consicely with:

$ [data is generated] | awk '! /something/'

which isn’t too bad at all.

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