Shell Programming and Scripting

Hi folks,

I've been using grep -f file1 file2 to get lines that match a file1 line from file2. I'm now interested in getting the lines from file1 where there was no match in file2.

I believe the -v option will give me unmatched lines from file2, but I'm looking for unmatched lines from file1. Is there a slick option here? Or do I just need to write a script.

Thanks,

Sanjuro

Perhaps you can use

Code:

grep -vf file2 file1

If not, could you post sample input and result?

file1:
a
b
c
d
e

file2:
aaaaa
bbbbb
ccccc
ddddd

Output desired:
e

Output of grep -vf file2 file1:
a
b
c
d
e

Output of grep -vf file1 file2: (nil)

Code:

while read str
do
grep -q "$str" file2
if [ $? -eq 1 ]; then echo $str; fi
done < file1