[TUHS] SCCS

[Steffen Nurpmeso]

Bakul Shah wrote in <20190913214905.339ED1570CE9 at mail.bitblocks.com>:
 |On Fri, 13 Sep 2019 14:17:51 -0700 Larry McVoy <lm at mcvoy.com> wrote:
 |> On Fri, Sep 13, 2019 at 11:11:04PM +0200, Steffen Nurpmeso wrote:
 |>> 
 |>> I for one am so happy to have git that i cannot tell you how much
 |>> that is.  I have used rcs, cvs, subversion, back to cvs,
 |>> mercurial over the years,, and for some small things also sccs.
 |>> All of it has been a pain here or there.  Yes, the weave.  Schily
 |>> wants to provide real changeset support for sccs (tagging is real
 |>> problem), i think.  
 |>
 |> I don't know why, BitKeeper does that and is open source under 
 |> a liberal license (Apache v2).
 |
 |This is because in git the "id" of a changeset is its sha1
 |checksum.  Given that, you can only reference it in a
 |subsequent changeset. This is a problem in that there is no
 |git built-in way to correlate a built binary with a particular
 |changeset id of its sources but you end up using your own
 |convention.  E.g.  set env. var VERSION or some such to the id
 |during the compile step but it is a bother.

Linus Torvalds wrote an interesting message on that many years
ago, which someone pointed me at ditto.  Do not ask.  git cannot
generate human readable things by design, with branching and
merging, and due to the distributed nature.  I have a little (git
pre-commit) script which keeps my SCCS IDs alive for my web pages,
even after i converted them to git.  But i think for code bases
like NetBSD in particular this is a total show stopper (they
really keep the "original" file preamble alive, do they?), but it
also is for OpenBSD i think, and for FreeBSD i know that having
a human readible sequentially increasing version number was a main
reason to go for subversion.  Even though there seems to be
a growing number of people who want to switch to git, yes i think
Warner Losh just said something like "when we will have switched
to git, that will xy", this week?

--steffen
|
|Der Kragenbaer,                The moon bear,
|der holt sich munter           he cheerfully and one by one
|einen nach dem anderen runter  wa.ks himself off
|(By Robert Gernhardt)