Sure.  And of course there will always be interpretations of how much one idea salted another.  But the seeds of the discomfort come from these various solutions and frankly how much the original authors were bought into/part of the integration process.  

On Wed, Sep 21, 2022 at 5:14 PM Theodore Ts'o <> wrote:
On Wed, Sep 21, 2022 at 10:57:51AM -0400, Clem Cole wrote:
> The legal term '*copyright*' and historical term of '*provenance*.'    I
> agree with Warner that I know of few if any cases where copyright was not
> maintained when it was in the code itself.  And as he points out, please
> grep through the archives and I think that will be found to hold true.
> But I also think Rob rankle comment is fair.  Joy and was noted for
> recognizing cool ideas and adding them into 'Berkeley UNIX.  The line at
> the time was he took ideas and '*peed on them to make them smell like
> Berkeley*.' For example, 'Berkeley Joy Control' came from Kulp via Europe
> and MIT, the network stack famously started at BBN, and a lot of the
> support for limits and user controllers from Australia.
> Yes, the CSRG team did do a great deal of innovation as well as
> integration, but the line between the two was not always easy to see from
> the outside.

Well, there can be a huge spectrum here, isn't there?   Ranging from:

* Take the code wholesale with no changes.

* Take the code and make changes to match with local coding style.

* Take the code and serially rewrite it so when you're done it
  only vaguely resembles the original contribution.

* Look at the code, get the ideas, and the reimplement it from
  scratch, keeping the existing interface (or using the existing
  interface as a starting point before extending it)

* Look at the code, get the ideas, and reimplent it from scratch
  with radically different interfaces.

It sounds like all of these were used to some extent as part of the
BSD/CSRG integration process; is that right?

                                                - Ted
Sent from a handheld expect more typos than usual