user1468315 user1468315 - 18 days ago 5
Bash Question

How to process each line received as a result of grep command

I have a number of lines retrieved from a file after running the grep command as follows:

var=`grep xyz abc.txt`


Let’s say I got 10 lines which consists of xyz as a result.

Now I need to process each line I got as a result of the grep command. How do I proceed for this?

Mat Mat
Answer

One of the easy ways is not to store the output in a variable, but directly iterate over it with a while/read loop.

Something like:

grep xyz abc.txt | while read -r line ; do
    echo "Processing $line"
    # your code goes here
done

There are variations on this scheme depending on exactly what you're after.

If you need to change variables inside the loop (and have that change be visible outside of it), you can use process substitution as stated in fedorqui's answer:

while read -r line ; do
    echo "Processing $line"
    # your code goes here
done < <(grep xyz abc.txt)