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yuubi

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A Tale of Two Feet 4 years ago

the inch changed in 1959 from exactly 1/39.37 m to exactly 2.54 cm; the survey foot is for compatibility with large-scale measurements based on old inches.

the story seems to be set in a world that uses gas to weld steel as part of a production process, making a blue flame. are there any torches that can weld steel and make a blue flame? does anyone use manual gas welding in automotive production‽

part of the deal with cable tv a few decades ago was that the cable channels didn't have ads because you paid for them directly every month. (local stations obviously had their usual ads).

sunos4 disk devices were named like xy0a or xd2h or sd1b. the first 2 letters were the controller (xy/xd were different types of xylogics smd controllers, sd scsi), the number was the unit number, and the letter was the partition, with some fairly strong conventions (a=root, b=swap, c=whole disk, d..h=other)

the search is to generate a valid signing key pair, where "valid" means the last 28 bits are as specified. once a poster generates such a key, they can use it for as long as it's valid.

erlang/otp gen_fsm maybe?

you define a function with a clause per state (and some other args including the incoming message), and each clause returns a tuple with the new state and some other stuff. the loop is part of the framework, and handles generic otp stuff like updating code in a running system.

Standard C provides only a few ways to obtain valid pointers. implementations can define behaviors in cases that the standard leaves undefined, such as allowing more cases of casts of integers to pointers than the standard defines (common in embedded-land), or functions like mmap or sbrk. so you or your chip vendor could define FOO_REG as (uint32_t )0x80001234 and use it as if it were a variable.

Olde C used to just let you use integers as struct pointers, and there was only one struct member namespace. so code like this was valid and did an integer-size write to address 0177770. old unix did this for device register access; see the lions book.

struct { int integ; };

f() { 0177770->integ = 012345; }

however, the safe logoff button avoids emergency warp. in exchange for sitting in space without maneuvering or activating modules for 30 seconds, you disappear immediately when the time runs out. at least this was the mechanic a couple of years ago.

Dolby digital could be used without replacing much existing equipment: the sound head looked like it bolted right onto the 1940s-vintage projector in the one installation I've seen. would look like it belonged if the projector wasn't gray wrinkle paint and the sound head smooth black finish. yes, several parts have been updated, including the light source and a platter system, but again it looks like none of this involved doing any violence to the actual projector.

the 6502 has a single 16-bit address space with some parts (zero page, stack) addressable by means other than full 16-bit addresses. the 8051 has 16-bit read-only code space, 16-bit read/write external memory space, and 8-bit internal memory space, except half of it is special: if you use indirect access (address in an 8-bit register), you get memory. but if you encode that same address literally in an instruction, you get a peripheral register.

at least that's the part I remember

GPL 2 says "machine-readable", which I read as meaning on a tape or ftp site or something in a useful form, not handwritten on paper or similarly useless form. Also, I doubt obfuscated code would comply with the "preferred form" part.

I don't think I've ever seen any of the stickers from the telegram company actually used in a chat. I've seen lots of stickers that people have had drawn, though, sometimes even used by the people who commissioned them.

The ldd program that lists the shared libraries used by an executable at least used to exec with an empty argv, which the dynamic linker detected and listed libraries instead of linking and running. I learned that when I screwed up an inetd configuration and saw a list of libraries instead of the desired results.

Edit: just tried on windows 10 WSL, and it had a sad (blue screen).

Routed Gothic Font 4 years ago

Letter shapes usually have curves a bit more complicated (in the sense of "how many parameters do I have to write down to reproduce it?") than this typeface. It feels like it's made of straight segments and ellipses, and all the strokes are uniform width and have round ends.

Also, the 'a' and 't' look like the kindergarten versions instead of the more usual two-story 'a' and 't' with some sort of curve at the bottom.

Most of this is almost certainly driven by the context this typeface was designed for. The simple shapes probably come from usability considerations for the lettering machine: the user had to trace each stroke in the template by hand. The uniform stroke weight and rounded ends come from how the engraving tool worked: basically a drill bit you drag sideways.

The curves are probably that way because there was a fashion for "modern" shapes a while back, which meant roughly "describable with a simple formula and few parameters"

We're accustomed to typefaces that were designed for use in movable type, where variable stroke weights and end shapes are basically free.

can read the binary encodings almost like it is text.

I'm curious what encoding rules that applies to: BER/DER I could easily believe, aligned PER a bit less so, and unaligned PER with lots of extensions and optional parts would be impressive.