On 8 September 2017 at 07:55, Antoine Pitrou <solip...@pitrou.net> wrote: > On Fri, 8 Sep 2017 07:49:46 -0700 > Nick Coghlan <ncogh...@gmail.com> wrote: >> > I'd rather a single magic number and a separate bitfield that tells >> > what the header encodes exactly. We don't *have* to fight for a tiny >> > size reduction of pyc files. >> >> One of Benjamin's goals was for the existing timestamp-based pyc >> format to remain completely unchanged, so we need some kind of marker >> in the magic number to indicate whether the file is using the new >> format or nor. > > I don't think that's a useful goal, as long as we bump the magic number.
Yeah, we (me, Benjamin, Greg) discussed that here, and we agree - there isn't actually any benefit to keeping the timestamp based pyc's using the same layout, since the magic number is already going to change anyway. Given that, I think your suggested 16 byte header layout would be a good one: 4 byte magic number, 4 bytes reserved for format flags, 8 bytes with an interpretation that depends on the format flags. Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
