Bash query

[Silverflames]

I've got two files. They both contain package names. Is there any way I can go through the package list on one file, and search to see if each package exists in the other file? What I'd want to do, is if the package name is found in the the main file, then go to the next line. If its not found then print that package name to another file.

I know you can use diff, but it doesn't seem to be that straight forward. As I understand it diff searches line by line, so if line one doesn't match line one in another file, then it prints it out. That's not exactly what I want.

I just really need an easy way to filter out the additional packages that exist on a new server. If I have a list of packages that aren't on the original server, then i can just delete them.

Not sure if I've made any sense but there must be a quicker way to do what i need to. It would take me ages to scan manually through the package names in each list, and highlight the ones i dont need.

[Irithori]

What about this:

sort list1 |uniq > sorted_list1
sort list2 |uniq > sorted_list2

diff sorted_list1 sorted_list2

[drl]

Hi.

       comm [OPTION]... FILE1 FILE2

DESCRIPTION
       Compare sorted files FILE1 and FILE2 line by line.

       With  no  options,  produce  three-column  output.  Column one contains
       lines unique to FILE1, column two contains lines unique to  FILE2,  and
       column three contains lines common to both files.

-- excerpt from man comm, q.v.

Another method would be:

sort file1 file2 | uniq -u

note that this will list items that are unique in each file, but your description indicated that one would be a super-set of the other, i.e not of wildly different content.

If the files are not too long:

grep -v -f file1 file2

will avoid the sort ... cheers, drl