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Comment I'm a (minor) Multician (Score 1) 50

My truename appears in the list of "Multicians". I still have my copy of The Design of the Multics Operating System.

One of the things that Multics did better than anything since was a feature called dynamic linking. In Multics, linking to a DLL was done via a symbolic reference resolved at runtime, rather than a reference to an ordinal (as in Windows). The Multics file system allowed you to have multiple names on the same file. The combination of those two features resulted in the ability to hot-plug DLLs. Here's how:
1. You have a program which wants to take a sine function. It's got a link to "fortran.lib:sin" (no, the Multics syntax for the entry point was different, but you get the idea).
2. The fortran guru decides he wants to upgrade the fortran library while your program is running.
3. When your program first invoked the sin() function, the symbolic link is resolved to the existing fortran.lib DLL and it's loaded into your pdd (process space).
4. The fortran guru adds the name "fortran.lib_bak" to the existing library file.
5. The fortran guru creates his library as "fortran.lib_new".
6. The fortran guru moves the name "fortran.lib" from the old library to the new one.
7. Immediately, user programs which have not already linked to the old DLL will now link to the new one as symbolic references are encountered and resolved.
8. The fortran guru removes the name "fortran.lib_new" from his new library, which has no effect except to free up that name for use in a future upgrade.
9. Eventually, all user programs which referenced the old library finish and the old library can be deleted. Everyone now uses the new library,

When I first learned about this, I thought is was really cool. 35 years later, I still do.

Comment I have an observation (Score 1) 5

I have maintained for years that if you want to assess a society's technological level there are two fields you need to examine. The first -- and sadly, probably the most obvious -- is weaponry. But the second is music-making. No matter what the level of technology a society is capable of, the highest available tech seems to always wind up in their musical instruments. If you have a stick and a hollow log, you make a drum. If you can make a bow, you make a one-string guitar. If you can drill a hole in a piece of wood, you make a flute. If you can smelt brass, you make a horn. Or a gong.

One example: one of the first electronic musical instruments was the Theremin. It was invented when the ink on the patent for the vacuum tube was barely dry. Another example: one of the earliest computer programs played music.

Disclaimer: I am not an anthropologist. I'd be interested in knowing a counterexample, though.

Comment Asimov himself described a big flaw in his 3 laws (Score 2) 255

He wrote an essay pointing out that the biggest problem with his three laws of robotics was that a robot might well have trouble defining "human". His test cases -- if I remember right; it was 40 years ago that I read the essay -- were (1) a baby [human but not competent to give a robot an order], (2) an adult with mechanical prosthetics [human only if you examine the right parts], (3) another robot and (4) a chimpanzee. The problem is a lot more complicated than the Three Laws makes it sound!

Comment One word: food (Score 1) 302

When the technology reaches the point where you can use a 3D printer to decorate a cake or make fancy chocolates by the dozen (hopefully, make both and other things besides) in a matter of minutes then a 3D printer will find space next to the coffee maker. At least in the sort of home where a gourmet kitchen would see daily use.

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