UNIX for Dummies Questions & Answers

I have a list of patterns (regexes) in a file and use with `grep -f <file_with_list_of_regexes.txt> input.txt` to search in my input for those patterns. grep is doing a fantastic job at it and finds me the matching input text but I also want to see in the output the regex (from file_with_list_of_regexes.txt) when it shows a matching text from the input. That is, let's say, I have the following two regexes in file_with_list_of_regexes.txt:

and my input text (input.txt) has the following two lines:

Now, if I use

Code:

grep -E -f file_with_list_of_regexes.txt input.txt

I am looking for a way that also displays the lines in file_with_list_of_regexes.txt in the output of the above command. something like:

It would do even if there is a way to show the line number in file_with_list_of_regexes. something like:

I don't think there's a built-in option in grep that does it. Just wondering if there are 'advanced' greps out there that has such an option or other ways to do this ..

I appreciate any ideas.

See if this awk fills your needs (presumes regex file has no spaces) :

Code:

awk 'NR==FNR { a[$1]; next } { for ( i in a) if (match($0,i)) print FNR FS i FS $0 }' file_with_list_of_regexes.txt input.txt
1 computer.+ sell your computer and buy a guitar
2 ^coffee.+ coffee time is anytime

Hope that helps.

Regards
Peasant.