Question

Let’s say we have two files.

match.txt: A file containing patterns to match:

fed ghi
tsr qpo

data.txt: A file containing lines of text:

abc fed ghi jkl
mno pqr stu vwx
zyx wvu tsr qpo

Now, I want to issue a grep command that should return the first and third line from data.txt:

abc fed ghi jkl
zyx wvu tsr qpo

… because each of these two lines match one of the patterns in match.txt.

I have tried:

grep -F -f match.txt data.txt

but that returns no results.

grep info: GNU grep 2.6.3 (cygwin)
OS info: Windows 2008 R2

Update: The fix is to use this command: tr -d "\r" <match.txt | grep -F -f - text.txt

It seems that grep does not correctly respect windows line endings (CR/LF) for match files presented to it via the -f flag.

Answer 1

I just tried exactly the example you gave and it worked as expected.

[~] $ grep -F -f match.txt data.txt 
abc fed ghi jkl
zyx wvu tsr qpo

Can you give more information? What OS are you running? What version of grep? What line endings do your input files contain?