Copy only difference (kdiff, winmerge, any diff like tool)

Question

Is there possibility of copy ONLY difference of two files? Like in winmerge, but, I can\'t find this option

Answer 1

Most diff tools have a patch generation functionality which can work toward the clipboard, this is mostly what you want as you will get only changed text on left and right side (if you remove the context lines). If you want only those of one side you can easily filter the patch with regard to the first character (removing all lines, using an editor, matching something like ^[+>].*$ to keep removed lines or ^[-<].*$ to keep added lines).

The diff tool in command line will output just that, piped with a grep and one of the above regular expression you are done.