<div dir="ltr">I had people relate to me, at least once, cases of utterly independent implementations of a function that were byte for byte the same, as found in one court case a friend of mine (now deceased) got pulled into. He had to prove he'd written his code from scratch. But these were pretty simple functions. I don't know if bmap qualifies ...<div><br></div><div>How could this happen? I don't know, but the court case that long predated SCO. The only conclusion I can reach</div><div>is that when enough techniques, ideas, mailling lists, discussions, and documents become part of a shared culture, the code which people create might be the same. A weird parallel evolution of code. </div><div><br></div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Nov 4, 2024 at 5:09 PM Larry McVoy <<a href="mailto:lm@mcvoy.com">lm@mcvoy.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">The thing I never got a reasonable answer to was I found code in BSD that<br>
was identical to code going back to at least V7. Find bmap() in the UFS<br>
code and then find the same in V7. I might be wrong about V7, might be<br>
32V, might be V6. I don't think it matters, it's the same in all of them.<br>
<br>
bmap() is the code that maps a logical block to a phsyical block,<br>
I'm quite familiar with it because I rewrote it to bmap_write() and<br>
bmap_read() as part of making UFS do extents:<br>
<br>
<a href="http://mcvoy.com/lm/papers/SunOS.ufs_clustering.pdf" rel="noreferrer" target="_blank">http://mcvoy.com/lm/papers/SunOS.ufs_clustering.pdf</a><br>
<br>
When all the lawsuits were going on, since I knew that code really well,<br>
I went off and looked and the BSD code at that time had bit for bit<br>
identical bmap() implementations. <br>
<br>
I never understood why BSD could claim they rewrote everything when they<br>
clearly had not rewritten that.<br>
<br>
I've raised this question before and I just went and looked, bmap() has<br>
changed. I'm pretty sure I have Kirk's BSD source releases, if I do, <br>
I'm 100% sure I can back up what I'm saying. Not sure I care enough to<br>
do so, it's all water under the bridge at this point.<br>
-- <br>
---<br>
Larry McVoy Retired to fishing <a href="http://www.mcvoy.com/lm/boat" rel="noreferrer" target="_blank">http://www.mcvoy.com/lm/boat</a><br>
</blockquote></div>