Linux cli pipeline command tail and grep

olo

12/21/22, 7:45 AM

I am using tail to monitor a log file and using grep to filer the keyword.

tail -F somefile.log | grep "keyword" is working tail -F somefile.log | awk '{print $4}' is working

but if to put them together is not working, like tail -F somefile.log | grep "keyword" | awk '{print $4}'

Is this the wrong way to use |? How to make tail -F somefile.log | grep "keyword" | awk '{print $4}' to work? Thanks

if I want to run a command after awk like tail -F somefile.log | grep "keyword" | awk '{print $4}' | ./abashfile.sh how to achieve something like this, looks like multiple | is not quite right for combining everything in 1 line. Thanks

1 + 1

linux

grep

tail

command

Michael Hampton

12/21/22, 6:12 PM

It seems fine. What exactly do you mean by "not working"?

Score:1

Server

digijay

12/21/22, 7:59 AM

You can do it with awk alone:

tail -f somefile.log | awk '/keyword/ {print $4}'

0 + 3

olo

12/21/22, 9:36 AM

Thanks for the answer, I am trying to figure out multiple `|`. eg I want to run a command after print `tail -f somefile.log | awk '/keyword/ {print $4}' | echo "received" >> file` looks the extra `|` is not something to be used?

digijay

12/21/22, 10:00 AM

You can combine as many pipes as you want/need in one line. What exactly is not working for you?

olo

12/21/22, 10:34 AM

Thanks! I wanted to do something like `tail -f somefile.log | awk '/keyword/ {print $4}' | echo {print $4}(get the result) >> filename (to another file)`

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Linux cli pipeline command tail and grep

TH: หางคำสั่งไปป์ไลน์ Linux cli และ grep

RO: Linux cli pipeline command tail și grep

RU: Команда конвейера Linux cli tail и grep

VI: Linux cli đường dẫn lệnh đuôi và grep

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