Grep – How to Run Grep with Multiple AND Patterns

grepregular expression

I would like to get the multi pattern match with implicit AND between patterns, i.e. equivalent to running several greps in a sequence:

grep pattern1 | grep pattern2 | ...

So how to convert it to something like?

grep pattern1 & pattern2 & pattern3

I would like to use single grep because I am building arguments dynamically, so everything has to fit in one string. Using filter is system feature, not grep, so it is not an argument for it.

Don't confuse this question with:

grep "pattern1\|pattern2\|..."

This is an OR multi pattern match.

Best Answer

agrep can do it with this syntax:

agrep 'pattern1;pattern2'

With GNU grep, when built with PCRE support, you can do:

grep -P '^(?=.*pattern1)(?=.*pattern2)'

With ast grep:

grep -X '.*pattern1.*&.*pattern2.*'

(adding .*s as <x>&<y> matches strings that match both <x> and <y> exactly, a&b would never match as there's no such string that can be both a and b at the same time).

If the patterns don't overlap, you may also be able to do:

grep -e 'pattern1.*pattern2' -e 'pattern2.*pattern1'

The best portable way is probably with awk as already mentioned:

awk '/pattern1/ && /pattern2/'

With sed:

sed -e '/pattern1/!d' -e '/pattern2/!d'

Please beware that all those will have different regular expression syntax.

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