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| From | Fritz Wuehler <fritz@spamexpire-201105.rodent.frell.theremailer.net> |
|---|---|
| Newsgroups | alt.sys.pdp11, comp.sys.dec, vmsnet.pdp-11 |
| Subject | Re: Y3K for PDP-11 Operating Systems |
| References | <irm17p$s8g$1@Iltempo.Update.UU.SE> |
| Message-ID | <982e99c70332e762155dff3bb558fd4b@msgid.frell.theremailer.net> (permalink) |
| Date | 2011-05-27 03:30 +0200 |
| Organization | Frell Anonymous Remailer |
Cross-posted to 3 groups.
Johnny Billquist <bqt@softjar.se> wrote: > On 2011-05-26 01.03, Fritz Wuehler wrote: > > billg999@cs.uofs.edu (Bill Gunshannon) wrote: > > > >> I guess the problem with that would be which Unix? :-) > >> And even among similar OSes that doesn't always work. BSD has > >> "Linux Compatability" but I have seen more programs that didn't > >> work under it than did. > > > > That doesn't make sense. As far as I know it works 100%. > > Oh, believe me, it does not. I can easily give you a list of Linux > programs you can not run on a BSD system, with Linux compatibility. > Not all system calls are emulated perfectly, and sometimes programs have > additional tricks going on out in the system, which is even harder to > emulate. I only have experience with Linux emulation under NetBSD but in two years of using it with several programs I never saw anything break. I try to avoid it though and now I am much more careful not to build anything with Linux dependencies on BSD systems. I really don't like the bloat and RH libs. I guess bottom line is for maybe a hardcore user you can find stuff that doesn't work. I don't think a normal desktop user who uses Linux emulation will run into problems. Maybe I am wrong but at least the solution is easy. > It's two different things. And one does not imply the other. > Implementing VMS as a library/program on top of Linux is a whole > different ballpark than writing a CPU emulator on top of Linux. I didn't read in the thread anybody was crazy enough to implement VMS on top of Linux. I wouldn't wish that on my worst enemy. Ok, maybe I would. The emulators I know aren't Linux-specific anyway. If you are going to really rewrite VMS or any OS I don't know of any reason except trying to be el-cheapo like an accountant to do it on top of an existing (broken, since we agree all the modern choices suck) OS. Write it to run on the metal. There are enough guys around who can still write x86 assembly who should be able to make it happen. I hate x86 but there aren't much choices. I dread having to code on a PC since nothing I like runs on one. I am very happy with my work machines (z/OS). Maybe ARM or some other RISC chip will come back now that Intel is moving away from desktop and we can actually have a good processor to code on again. > The requirements for the emulator of the CPU is that you need to perform > the rather well defined, and limited set of operations that the CPU > perform. That's not true. I can think of at least two major architectures where although the ISA is defined, many things are implementation specific. Sparc and System Z fall into those categories. If you think it's a simple matter of just hard work to write a Z emulator like they did (Hercules390.org) then look at the IBM manual called z Architecture Principles of Operation. I think it's about 1600 pages. That's just the description of the ISA and CPU environment. Nothing about the OS is included. Even pure x86 emulation today would be extremely difficult, the instruction set is huge. > The OS on the other hand have a very rich set of functions and features. > Mostly well documented, admittedly, but some of those functions can be > much harder to implement on a OS that have a different paradigm. Right, so do it on the metal. The whole point is making the OS you want. Why cripple it from the start by tying it to a system you don't want? Interesting what Palm did in their last versions. All Palm was M68K until the last models, they started to use ARM cores. They built a hardware emulation layer of M68K on the ARM so 68K or ARM code would run. If you want to approach the VMS project in a similar way you could begin by writing a VMS emulation layer on x86 and then writing your OS on top of the VMS architecture as if there were no x86 issues. Having the emulation layer separated from the OS will make everything nice and clean. It will also give you the capability to run the same OS on FPGA if you code your emulation layer, you won't have dependency on the metal. You will only have an architectural dependency, and it will be safe and sound back here in 1955 all over again. Main point I think is to break up the project into creating emulated VAX machine and new VMS OS. That is what I would do. If you can live with the old OS and you can obtain copies then all you have to do is write the hardware emulation and you don't even need to write the OS. I don't know VMS but in general this approach sounds good and doable with any OS rewrite IF the OS you want to rewrite was targeted for a different architecture. Some OS are more or less hardware centric and what I suggest is for those that are very hardware centric because z/OS for example is very much like that. As we know, Linux and UNIX are much less so. It all depends on how the OS and hardware work together and were designed.
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Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-04-04 09:12 -0400
Re: Y3K for PDP-11 Operating Systems billy@MIX.COM - 2011-04-30 22:27 +0000
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-01 10:01 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-01 10:27 -0700
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-01 20:53 -0400
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-01 21:16 +0000
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-01 20:54 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-01 21:07 -0700
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-02 09:37 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-02 08:39 -0700
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-02 05:15 +0000
Re: Y3K for PDP-11 Operating Systems jjh <jjhudak@gmail.com> - 2011-05-02 18:20 -0700
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-03 08:18 -0500
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-03 12:51 -0400
VAXTREK koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-03 12:50 -0500
Re: Y3K for PDP-11 Operating Systems Henry Crun <mike@rechtman.com> - 2011-05-03 21:39 +0300
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-03 15:56 -0400
Re: Y3K for PDP-11 Operating Systems onedbguru <onedbguru@yahoo.com> - 2011-05-03 15:52 -0700
Re: Y3K for PDP-11 Operating Systems billig999@cs.uofs.edu (Bill Gunshannon) - 2011-05-04 00:07 +0000
Re: Y3K for PDP-11 Operating Systems "Richard B. Gilbert" <rgilbert88@comcast.net> - 2011-05-04 01:16 -0400
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-04 13:01 +0000
Re: Y3K for PDP-11 Operating Systems "Richard B. Gilbert" <rgilbert88@comcast.net> - 2011-05-04 10:19 -0400
Re: Y3K for PDP-11 Operating Systems kludge@panix.com (Scott Dorsey) - 2011-05-04 10:58 -0400
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-04 16:33 +0000
Re: Y3K for PDP-11 Operating Systems "Richard B. Gilbert" <rgilbert88@comcast.net> - 2011-05-04 21:51 -0400
Re: Y3K for PDP-11 Operating Systems G Cornelius <cornelius@eisner.decus.org> - 2011-05-06 13:08 -0500
Re: Y3K for PDP-11 Operating Systems "Richard B. Gilbert" <rgilbert88@comcast.net> - 2011-05-06 14:47 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@update.uu.se> - 2011-05-06 16:13 -0600
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-07 21:00 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-07 19:51 -0600
Re: Y3K for PDP-11 Operating Systems "Richard B. Gilbert" <rgilbert88@comcast.net> - 2011-05-08 07:19 -0400
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-09 17:32 -0400
Re: Y3K for PDP-11 Operating Systems Rob Brown <mylastname@gmcl.com> - 2011-05-09 09:40 -0600
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-09 09:43 -0600
Re: Y3K for PDP-11 Operating Systems vandys@vsta.org - 2011-05-09 21:47 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-09 16:05 -0600
Re: Y3K for PDP-11 Operating Systems vandys@vsta.org - 2011-05-09 23:05 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-09 17:20 -0600
Re: Y3K for PDP-11 Operating Systems vandys@vsta.org - 2011-05-10 00:12 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-09 19:36 -0600
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-10 02:01 +0000
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-10 08:31 -0500
Re: Y3K for PDP-11 Operating Systems John Wallace <johnwallace4@yahoo.co.uk> - 2011-05-10 09:56 -0700
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-10 12:50 -0500
Re: Y3K for PDP-11 Operating Systems G Cornelius <cornelius@eisner.decus.org> - 2011-05-11 11:04 -0500
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-04 10:02 -0700
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-04 12:20 -0500
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-04 18:10 +0000
Re: Y3K for PDP-11 Operating Systems John Wallace <johnwallace4@yahoo.co.uk> - 2011-05-04 12:21 -0700
Re: Y3K for PDP-11 Operating Systems MetaEd <metaed@gmail.com> - 2011-05-04 15:06 -0700
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-04 20:17 -0700
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-10 08:20 -0500
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-10 08:29 -0500
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-10 09:29 -0600
Re: Y3K for PDP-11 Operating Systems G Cornelius <cornelius@eisner.decus.org> - 2011-05-10 12:16 -0500
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-10 12:45 -0500
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-10 15:34 -0600
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-10 12:58 -0500
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-10 15:36 -0600
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-03 12:38 -0400
Re: Y3K for PDP-11 Operating Systems paramucho@hotmail.com (paramucho) - 2011-05-03 11:28 +0000
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-03 12:09 -0400
Re: Y3K for PDP-11 Operating Systems billy@MIX.COM - 2011-05-23 03:41 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-22 21:51 -0700
Re: Y3K for PDP-11 Operating Systems jjh <jjhudak@gmail.com> - 2011-05-23 07:47 -0700
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-23 15:04 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-23 15:52 -0700
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-24 00:16 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-23 17:40 -0700
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-24 12:58 +0000
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-24 14:02 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-24 07:36 -0700
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-24 16:42 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-24 11:17 -0700
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-24 20:07 +0000
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-24 21:07 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-25 03:34 -0700
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-25 15:46 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-25 16:00 -0700
Re: Y3K for PDP-11 Operating Systems Fritz Wuehler <fritz@spamexpire-201105.rodent.frell.theremailer.net> - 2011-05-26 17:50 +0200
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-26 09:53 -0700
Re: Y3K for PDP-11 Operating Systems Fritz Wuehler <fritz@spamexpire-201105.rodent.frell.theremailer.net> - 2011-05-26 22:20 +0200
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-28 18:01 +0000
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-25 20:58 -0400
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-26 01:23 +0000
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-26 08:01 -0500
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-27 00:54 +0000
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-26 16:15 -0400
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-26 23:56 +0000
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-27 14:37 -0400
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-27 00:02 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-26 20:17 -0700
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-27 14:51 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-27 12:48 -0700
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-27 14:35 -0400
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-25 21:14 -0400
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-26 01:32 +0000
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-26 16:39 -0400
Re: Y3K for PDP-11 Operating Systems Fritz Wuehler <fritz@spamexpire-201105.rodent.frell.theremailer.net> - 2011-05-26 17:50 +0200
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-24 21:01 -0400
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-26 07:53 -0500
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-26 09:59 -0700
Re: Y3K for PDP-11 Operating Systems Fritz Wuehler <fritz@spamexpire-201105.rodent.frell.theremailer.net> - 2011-05-26 10:03 +0200
Re: Y3K for PDP-11 Operating Systems paramucho@hotmail.com (paramucho) - 2011-05-26 14:21 +0000
Re: Y3K for PDP-11 Operating Systems billy@MIX.COM - 2011-05-26 18:50 +0000
Re: Y3K for PDP-11 Operating Systems paramucho@hotmail.com (paramucho) - 2011-05-27 11:58 +0000
Re: Y3K for PDP-11 Operating Systems billy@MIX.COM - 2011-05-27 17:23 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-26 10:04 -0700
Re: Y3K for PDP-11 Operating Systems Fritz Wuehler <fritz@spamexpire-201105.rodent.frell.theremailer.net> - 2011-05-27 03:30 +0200
Re: Y3K for PDP-11 Operating Systems kludge@panix.com (Scott Dorsey) - 2011-05-26 22:17 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-26 20:26 -0700
Re: Y3K for PDP-11 Operating Systems John Wallace <johnwallace4@yahoo.co.uk> - 2011-05-30 14:09 -0700
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-30 18:15 -0700
Re: Y3K for PDP-11 Operating Systems jjh <jjhudak@gmail.com> - 2011-05-31 11:02 -0700
Re: Y3K for PDP-11 Operating Systems koehler@eisner.nospam.encompasserve.org (Bob Koehler) - 2011-05-31 15:54 -0500
Re: Y3K for PDP-11 Operating Systems glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2011-05-31 21:37 +0000
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-24 22:59 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-25 03:51 -0700
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-25 08:36 -0400
Re: Y3K for PDP-11 Operating Systems "Tom Lake" <tlake@twcny.rr.com> - 2011-05-25 13:25 -0400
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-25 14:01 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-25 11:44 -0700
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-25 21:20 -0400
Re: Y3K for PDP-11 Operating Systems Rob Brown <mylastname@gmcl.com> - 2011-05-26 10:53 -0600
Re: Y3K for PDP-11 Operating Systems Rich Alderson <news@alderson.users.panix.com> - 2011-05-26 16:27 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-26 20:27 -0700
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-26 16:38 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-26 21:44 -0700
Re: Y3K for PDP-11 Operating Systems paramucho@hotmail.com (paramucho) - 2011-05-24 12:02 +0000
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-23 10:48 -0400
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-23 15:46 -0700
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-24 00:19 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-23 17:43 -0700
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-25 14:41 -0400
Re: Y3K for PDP-11 Operating Systems billy@MIX.COM - 2011-05-24 02:54 +0000
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-24 13:03 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-24 07:39 -0700
Re: Y3K for PDP-11 Operating Systems billy@MIX.COM - 2011-05-24 15:10 +0000
Re: Y3K for PDP-11 Operating Systems Johnny Billquist <bqt@softjar.se> - 2011-05-24 08:48 -0700
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-24 16:54 +0000
Re: Y3K for PDP-11 Operating Systems billy@MIX.COM - 2011-05-24 14:42 +0000
Re: Y3K for PDP-11 Operating Systems billg999@cs.uofs.edu (Bill Gunshannon) - 2011-05-24 16:56 +0000
Re: Y3K for PDP-11 Operating Systems "Jerome H. Fine" <everyone@nospam.com> - 2011-05-25 14:05 -0400
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