Using diff and erasing the lines that match

ElectroLinux · 09-20-2006, 02:21 AM

How do I diff two files and erase the lines that are the same without having to go into an editor?

So if i have

List A
1
2
3
4
5
6

List B
2
4
6

If i diff these two files, i'd want to be able to have
List A -B = C

List C
1
3
5

Zmyrgel · 09-20-2006, 03:20 AM

Pipe is your friend. Also check sed and awk as they would be helpfull.

I think something like "diff list_A list_B > list_C" would work.

ElectroLinux · 09-20-2006, 03:30 AM

No, that would just get me output of the diff...i want to actually get rid of any lines that match in List B.

druuna · 09-20-2006, 03:31 AM

Hi,

Using one command:

comm -3 list_A list_B

man comm for details.

Hope this helps.

ElectroLinux · 09-20-2006, 03:34 AM

That is exactly what I was looking for. THANKS!