I taught some C to my sis today and it's hard because she is smart and has questions
like, I wasn't prepared to have to explain PRNGs but I had to coz she wanted to know how random number generation is done because I mentioned that "int x;" gets a random number and she asked "so if I want a random number I should just look at some random memory location" and I couldn't in good conscience say "yeah, that is a perfectly valid way to do RNG"
@grainloom function that gets a random uint8_t by continually spawning a subprocess that attempts to dereference a random memory address. when eventually one doesn't segfault, it returns that byte. warning: random number distribution is heavily biased to 0 and also quite biased to 255
@jk upon reading this toot Dennis Ritchie's ghost manifested in my room, took the UNIX manual from my shelf and smashed my laptop with it
@starbreaker @grainloom the implementation isn’t silly enough im afraid
@jk @starbreaker @grainloom go look again, it's randomly silly
@djsundog @jk @starbreaker @grainloom reimplement libc with a focus on maximizing implementation silliness
@djsundog @jk @starbreaker @grainloom oh wait that's just called msvc whooooops
@io @grainloom @starbreaker @jk @djsundog reimplement libc by shelling out to, well, shell utilities.
did I reinvent plan9 yet?
@grainloom @Shamar @io @starbreaker @jk @djsundog memory should be a file.
the only syscalls should be mmap and system.
@SoniEx2 @djsundog @jk @starbreaker @io @grainloom
I suggest you to try implement an OS with such approach, just for fun.
But that's now how I design syscalls for #Jehanne.
It's core abstraction is the file (for a certain definition of #file).
All services that can be exposed as file operations, are. Process memory allocation, for example, is done with a create() of a file; current time is done with a remove() of another file.
@Shamar @grainloom @io @starbreaker @jk @djsundog strcpy(mmap("/sys/mkfile", ???), "/tmp/memory"); mmap("/tmp/memory", ???); etc
@SoniEx2 @djsundog @jk @starbreaker @io @grainloom
This looks pretty weird to me.
I don't like mmap at all.
BUT, I will not be the guy who tell you to NOT hack something.
I strongly encourage you to try to write such OS. You might fail to create anything usable, but you will learn a lot in the process anyway.
Or you might succeed, showing everyone else that it was a good idea.
And I strongly encourage you to document the whole process, whatever the outcome: it's always worth to #hack.
@grainloom @SoniEx2 @djsundog @jk @starbreaker @io
Well, sure.
I'd suggest to look more into Plan 9 to anyone. 😉
But if someone propose an hack I find particularly weird (but not dangerous for anyone), my first reaction is: you should really try this! 👍
Any other reaction might discourage the hacker.
@grainloom @jk There's a standard library function for this.
http://www.cs.yale.edu/homes/aspnes/pinewiki/C(2f)Randomization.html#The_rand_function_from_the_standard_library