So lets say I have 5 files: f1, f2, f3, f4, f5. How can I remove the common strings (same text in all files) from all 5 files and put them into a 6th file, f6? Please let me know.

**Format of the files:**

```
property.a.p1=some string
property.b.p2=some string2
          .
          .
          .
property.zzz.p4=123455

```

So if the above is an excerpt from file 1 and files 2 to 5 also have the string *`property.a.p1=some string`* in them, then I'd like to remove that string from files 1 to 5 and put it in file 6. Each line of each file is on a new line. Thus, I would be comparing each string on a newline one by one. Each file is around 400 to 600 lines.

I found this on a forum for removing common strings from two files using ruby:
`$ ruby -ne 'BEGIN {a=File.read("file1").split(/\n+/)}; print $_ if a.include?($_.chomp)' file2`