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Comment: Two easy options (Score 2) 460

by Terje Mathisen (#49145225) Attached to: Ask Slashdot: Old PC File Transfer Problem

I have a Vantec USB2 universal disk adapter, it has connectors for IDE and SATA, with cables and power, for all the hard drives I've used since my last SCSI disk, this is the one I would use here. I picked mine up at Fry's many years ago, just as SATA disks had started to take over.

The alternative has also been mentioned, using a LapLink style cable: These packages usually came with selfloading sw where you just had to enter a single single MODE command on the console of the old machine, then the SW would copy over an ascii type bootstrap program which would load the rest.

I wrote a program to do this (the file transfer part) in the late eighties, in 1995 or so I also write a generic ascii executable generator using only those 70+ characters which the MIME mail standard specifies as transparent across all mail gateways and national encoding standards.


Comment: Re:Gurus like Carmack don't need agents (Score 1) 145

by Terje Mathisen (#49125219) Attached to: Attention, Rockstar Developers: Get a Talent Agent

Thanks for remembering, that time was a lot of fun. :-)

I'm still doing low-level programming, I've been involved with the Mill for a little more than a year now, I'm working on scalar/vector FP emulation for the smallest models we intend to produce.

Take a look at if you want to widen your mind a bit: A CPU with a belt instead of registers!


Comment: Gurus like Carmack don't need agents (Score 3) 145

by Terje Mathisen (#49119575) Attached to: Attention, Rockstar Developers: Get a Talent Agent

I've met John C a number of times, he is indeed a guru.

My longtime friend Mike Abrash is also a guru, but according to him, not in the same league as Mr Carmack.

Personally I'm a very competent programmer who've just had some small episodes of greatness: I know I'm not as bright as John or able to work for years at a single task like Mike can do, but I've still had a lot of fun over the last 35-40 years! :-)

Today I declined an offer to become CTO of a 20 year old international sw company, I'm having a pretty good time where I am now.


Comment: Duplicate the TLB code entries! (Score 2) 215

by Terje Mathisen (#49049485) Attached to: New Encryption Method Fights Reverse Engineering

To me it looks like this trick has a similar, very simple trick to defeat it:

Assuming you can run some code at kernel (or even SMM) mode, you should be able to scan through all code segments that are marked execute only, and which have a data segment which aliases it? I.e. same virtual address - different physical addresses.

When you find such blocks, you just create new readonly or readwrite mappings which points to the same physical addresses as the decrypted/execute-only memory.

At that point you can dump/debug to your heart's content.


Comment: Half of anything is below average! (Score 1) 580

by Terje Mathisen (#49045565) Attached to: Low Vaccination Rates At Silicon Valley Daycare Facilities

The report states that "6 out of 12 day care centers have below average vaccination rates", right?

So, if you take a random sample of _anything_, how many would you expect to be below the average for that particular measurement?

The news here isn't that high tech daycare centers have low vaccination rates, but that they don't have particularly high rates, i.e. they are totally average.


Comment: The company I work for blocked this last week (Score 1) 24

by Terje Mathisen (#49027467) Attached to: EU Parliament Blocks Outlook Apps For Members Over Privacy Concerns

After checking out how the Outlook app handles emails and authentication, our security group pushed out an update to the blocklists, making it impossible to install this app on any phone connected to our company mail servers. (Connecting to those email servers already requires you to accept a minimum set of company security requirements, like secure unlock, not just a swipe, and the capability to remotely wipe the phone.)


Comment: This is US-centric problem! (Score 1) 514

I live in Oslo, Norway, and I would claim that even though we also have our share of wooly/wishful thinking, most Norwegians tend to believe what scientists tell them, as opposed to the US where even presidents can boast about making decisions based on their gut feeling, with no factual research.

I am an EE who has been working in the IT business since 1984, but that doesn't mean that I don't try to follow research in other fields, like physics or chemistry.

Living in Norway I know that pretty much all the electricity we use here is based on hydro power, but I realized many years ago that for humanity in general to have a sustainable future we need a lot more research into nuclear power: It comes down to either filling up a fraction of the Sahara with solar cells, or developing better reactors like the Thorium LIFTer. Burning complex hydrocarbons for power generation should be a crime, and not just due to global warming.

I'll admit that I don't like GMOs, but that is mostly due to the way the US patent systems have allowed Monsanto to patent the resulting modified genes. It was really good news when the patent on the breast cancer gene sequence was invalidated, so I do have some hope that the US will try to fix the most glaring problems.


Comment: Re:Mathematics (Score 4, Informative) 79

by Terje Mathisen (#48774659) Attached to: OpenBSD Releases a Portable Version of OpenNTPD

[Full Disclosure: I have been a member of the NTP Hackers team for ~15 years, so you could claim that I'm partly to blame for the recent security problems even if I have not personally worked on the crypto or monitoring code.]

NTPD is definitely more complicated that what you need for a leaf (client-only) machine, like all the server functions and the code that support locally attached reference clocks, this is the main reason PHK is working on a dedicated NTP client.

We have known for many years that the monitoring functions, in particular the "mode 6" UDP packets were a potential DDoS amplification vector, which is why we replaced them.

For the crypto stuff we did what pretty much every other project did, i.e. we imported the functions we needed from openssl, and like pretty much every other project we messed up a few buffer handling issues.

The important point here is that anyone running a public server with a recommended configuration (no crypto, no remote monitoring) would not have had any security problems, even if they insisted on using 10+ year old versions!

With any version from withing the last 3-5 years you would also have been secure against the DDoS vector even if you did allow remote status monitoring.

How many system-level sw packages are you using where this would have bee true?

PS. OpenNTP should properly be called OpenSNTP, since it implements the Simple NTP subset instead of the full NTP protocol stack which includes system clock time/frequency tuning.

Comment: There's a reason it doesn't work! (Score 1) 464

by Terje Mathisen (#48725383) Attached to: Ask Slashdot: Are Progressive Glasses a Mistake For Computer Users?

I am 57, I have used reading glasses for about 10 years, then switched to progressive (+2.75 to +0.75 on my right eye, +2.0 to 0 on my left) about three years ago.

I really love these glasses but have found like you that they are not at all suitable for my standard 3-monitor working setup:

Progressive lenses work by having a fairly large sweet spot (i.e. focus area) over the top half of the lenses, optimized for distance vision, then a much smaller bottom area which is optimized for (book) reading, i.e. with a focus distance of 30+ cm or about a foot. It is important to note that this lower area is significantly narrower than the distance-vision part!

The big problem is everything in between, i.e. the progressive part! When you blend two different lenses, the transition area will be very narrow, i.e. the area of good focus is shaped like a top-heavy timing glass with a narrow waist.

This will severely limit your normal sidewise focusing ability, and the narrowest slice seems to be close to the 60-100 cm distances typical of multi-monitor setups.

The only good solution I've found is to have a pair of dedicated programming glasses in the +1.75 to +2.25 range.

BTW, what I'm really waiting for is improved soft replacement lenses which hook into my eye muscles so that I can focus the same I did when I was younger, but the first generation of these only provide about +1.0 of adjustable focus range, and that is not enough to read fine print, or in my case: Detailed orienteering maps.


Comment: Permanent conduits are the only way to go! (Score 1) 279

Here in Norway all electrical cables are installed inside plastic tubing, so you can pull out/replace them if you need to, with no need to tear down any walls. (BTW, we also do the same for water pipes: They are always installed as pipes-in-pipes, with a central drain point for the external pipes: This way any leak will be contained and you can fix it by pulling out the broken (usually due to freezing in winter) pipe and replace it.)

When we built a new home a few years ago I specified that the electricians should put in spare conduits between the main breaker room and every other room in the house, except bathrooms, this way I could pull whatever cable I would need.

PS. The sad part of the story is that the installation company had never done anything like this in a residential building before and they messed up badly, omitting the spare conduits to important locations like the living room/entertainment center. They ended up giving me a substantial rebate but I'm still a bit pissed off. :-(

Comment: BT, DT... (Score 1) 129

by Terje Mathisen (#47823515) Attached to: The Frustrations of Supporting Users In Remote Offices

Many, many years ago (1986 or so?) we had a branch oil exploration office in Iran, surveying new oil fields close to the border with Iraq.

Getting any kind of computer gear in or or out of the country was "difficult", and the best possible data connection was an extremely expensive 256 kbit/s satellite line.

One day I was told to help, over a bad phone line, a guy down in Teheran whose PcDos computer had crashed:

I was able to figure out that his crash had modified/overwritten the Boot Block on his hard drive, but that he did have a bootable Dos diskette available, so I sat for about 45 minutes on the phone, talking him through the DEBUG commands needed to load the boot block and manually modify it back to how it should have been, then write it back.

It worked on the first attempt. :-)


Comment: Mastery has to be (at least partly?) subconcious (Score 1) 160

by Terje Mathisen (#47542005) Attached to: Soccer Superstar Plays With Very Low Brain Activity

When grading expertise on any given task/process, the top level ("Master") is usually defined to be when the person can not even explain how she is doing it, everything is automated to such a degree that "the solution was obvious".

Magnus Carlsen used to play even faster than he is doing these days, but he explains that this is not because to takes him longer to figure out the best possible moves, but because he has to take the time afterwards to do all the required calculations to confirm his instinctual choices.

He has also explained after some really complicated end games where he has kept on playing for small advantages, eventually turning "obvious draws" into wins, that "it was very easy, I just had to play the only possible move".

I believe the foot/leg motor skills of a Neymar is comparable to those of a world champion orienteer: The best orienteers can run cross-country, through rocks, stones, windfall & vegetation, while studying an incredibly detailed map in order to navigate, making it impossible to focus on the ground while looking at the map. This means that the actual broken field running must use a small amount of brain capacity, all the movements are fully automated.

I know that Petter Thoresen (former multiple world champion) once was told to do a training race in Germany while a champion Kenyan cross country runner would tail him to check his technique: Even while orienteering Petter could run fast enough that the x-c runner was dropped after less than a mile.


Comment: Re:"poor night-time results": I do Night-Orienteri (Score 1) 550

by Terje Mathisen (#47529589) Attached to: Laser Eye Surgery, Revisited 10 Years Later

Thank you!!!

This is exactly what I've been waiting for, even if this first version only supplies a single diopter of focal plane adjustment:

Since orienteering maps are _very_ detailed I normally require +2 or more bifocal glasses in order to see all the fine detail clearly.

There is also a potential problem with the size of the lens: The visual opening is smaller than a natural or fixed replacement lens so the problem with night vision would still be there.

OTOH, this also means that the research is ongoing, I'm hoping for even better options in a few years. :-)


Computer Science is the only discipline in which we view adding a new wing to a building as being maintenance -- Jim Horning