On Wed, May 24, 2017 8:46 am, Warren Young wrote: > On May 24, 2017, at 6:02 AM, hw <hw at gc-24.de> wrote: >> >> Warren Young schrieb: >>> >>> CentOS 5 just left supported status, which shipped Perl 5.8.8 from >>> first release to last >> >> Living in the past seldwhen is a good idea. > > I don’t propose to teach you about my problems — they are, after all, > mine, and I’m coping with them quite well, thank you — but I’ll give > you a glimpse into someone else’s as a lesson: the San Francisco Bay > Area Rapid Transit System was still running on PDP-8s as of several years > ago, and may still be doing so. Warren, thanks a lot for this long and extremely instructive post!! I'm with you on all counts. Valeri > > As I understand it, they were using a modified PDP-8/e, which is 1970 > tech. Note that I didn’t say “1970’s.†I mean the year nineteen > hundred and seventy, A.D. The PDP-8/e is just an enhanced version of the > original PDP-8 from 1965, which is itself not a huge departure from the > PDP-5, from 1963. > > And you know what? The PDP-8/e is still well suited to the task. Trains > haven’t changed that much in the intervening decades, and the > construction techniques used by that era of computer mean it’s still > repairable with little more than a soldering iron. > > We have 40-cent microcontrollers with equivalent computing power to a > PDP-8/e today that run on far less power, but you’d have to pile up a > bunch of I/O interfacing in front of them to make it as electrically > capable and robust as a PDP-8/e, and you’d have to re-develop all the > software, too. > > The modern tendency would not be to use one of those 40-cent micros, it > would instead be to put a gigahertz class Linux PC in its place, with all > the concomitant risks. > > Try getting a modern Internet worm into a PDP-8! Good luck not blowing > the 4k word field boundary. > >>> If this sort of stance seems risible to you, you probably shouldn’t >>> be using CentOS. This is what distinguishes a “stable†type of OS >>> from a “bleeding edge†one. >> >> When a version of a software has been released 20 years ago, > > Eleven: https://dev.perl.org/perl5/news/2006/perl-5.8.8.html > > …which makes it younger than the C89 standard some still stick to over > in C land. And younger than C99. And younger than C++-98. And C++-93. > > By your lights, the C/C++ world is positive decrepit for not immediately > tossing everything and insisting on C11 and C++-14. > >> that doesn´t mean it´s more stable than a version of that >> software which is being released today. > > Actually, it does, provided it’s still being maintained, as Perl 5.8.8 > was up to a few months ago. Software that gets no new features also gets > no new bugs. Therefore, the overall bug count can only go down. > > The distinction you may be looking for is that there is a fine line > between “stable†and “moribund.†RHEL/CentOS rides that line much > closer than some other OSes, but it actively stays on the good side of the > line. > > After that end-of-support date, sometimes all it takes to slip over to the > bad side of the line is a new exploit or similar, but decades-old exploit > targets are very rare. > > More commonly, something changes in the environment to make the old > software unsuitable, as happened with BIND 4 and Apache 1.3. You > couldn’t drag either of those forward into the modern world without > major rework, so people running on them were forced to transition. > > I don’t see that happening with Perl 5.8. It was an uncommonly good > release of a language that was already quite stable by that point. It is, > after all, the fourth major version after Perl 5.0. You’d *expect* it > to be stable by that point. > > The only question then, is whether you can live without the new features. > I can. > >> what about the bug fixes? > > Red Hat was backporting them up until a few months ago. > > Now we just get to see how fast it bit-rots without Red Hat’s support. > > I don’t expect it to do so quickly. > >> Feature "signatures" is not supported by Perl 5.16.3 at … > > Again, see the docs: > > https://perldoc.perl.org/perlsub.html#Signatures > > I note that this feature is still marked experimental and subject to > removal. > > …And you’re lecturing me about stability? > _______________________________________________ > CentOS mailing list > CentOS at centos.org > https://lists.centos.org/mailman/listinfo/centos > ++++++++++++++++++++++++++++++++++++++++ Valeri Galtsev Sr System Administrator Department of Astronomy and Astrophysics Kavli Institute for Cosmological Physics University of Chicago Phone: 773-702-4247 ++++++++++++++++++++++++++++++++++++++++