fgrep pipes
 

Hi,
I have six files and I need to fetch the lines that are common among all of these files. Lets say I have 1.txt, 2.txt, 3.txt....6.txt. I was trying the following command.


$ fgrep -f 1.txt 2.txt | fgrep 3.txt | fgrep 4.txt .... | fgrep 6.txt > Common_among_all.txt


But this is not working :( Do anyone have any idea how to do this,, I will really appreciate your comments....Many thanks in advance :)

I did this using cat and uniq:
$ cat *.txt | sort | uniq -c | awk '{if ($1 ==6 ) print $0}'

Note that it works if identical lines are present only one time for each file
(eg it might fail if in one file, same line is present 6 times)

Based on this assumption, this perl line might also work:

You're almost there. You just need to tell each subsequent fgrep to use stdin as the file containing patterns to be matched. You should also use the "-x" option to insist that the whole line match.

u can use this....
grep -hf 1.txt 2.txt | grep -hf 3.txt | grep -hf 4.txt | grep -hf 5.txt | grep -hf 6.txt> common.txt

-f, --file=FILE obtain PATTERN from FILE
-h, --no-filename suppress the prefixing filename on output

also you can use if needed :

-w, --word-regexp force PATTERN to match only whole words
-x, --line-regexp force PATTERN to match only whole lines

hope this helps !!

Thank you all,, your suggestions are really helpful..many thanks :)