copy lines containing word from one file to another file in linux

Question

I want to copy lines containing certain words from file1 to file2.

Suppose file1:

ram 100 ct 50
gopal 200 bc 40
ravi 50 ct 40
krishna 200 ct 100

file2 should have only the lines containing "ct", which would look like this:

ram 100 ct 50
ravi 50 ct 40
krishna 200 ct 100

Which is the best way to achieve this? I had a file of 200mb. I used grep but I didn't get any result running grep -n ct file1.

Answer 1

This awk should do

awk '/ct/' file1 > file2

If position is important

awk '$3=="ct"' file1 > file2
awk '$3~/ct/' file1 > file2

last version is ok if ct is part of some in field #3

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Same with grep

grep ct file1 > file2

-n is not needed, since it prints line number

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Same with sed

sed -n '/ct/p' file1 > file2