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Comment Re:OSX is BSD Unix with Some Extras (Score 1) 134

I think it's just stupid that POSIX programs don't always work the way you expect or are missing (e.g. umount -> diskutil unmount )

umount's still there, and it works the same way it does on other UN*Xes - i.e., if some program has a handle (file descriptor, mapped file, etc.) on the volume to be unmounted, it fails (unless you use the -f flag, to forcibly invalidate those handles and unmount the file system). "diskutil unmount" sends a "hey, could you please let go of any handles you have for this?" request before the actual unmount() call is done, and waits a while for "OK, I've released it" replies before it attempts to unmount.

Unfortunately, a lot of stuff in macOS holds onto those handles - and some stuff just grabs them for the lulz as soon as something's recognized as having been mounted - so, as the umount(8) manual says, "Due to the complex and interwoven nature of Mac OS X, umount may fail often. It is recommended that diskutil(1) (as in, ``diskutil unmount /mnt'') be used instead."

(And it's not in POSIX; it's considered an administrative tool and UNIX(R) systems are allowed not to have it or to implement it as they choose.)

Comment Re:huh (Score 1) 134

I mean, fair enough, the OS code they release is only the code they "have" to release

Actually, as I said in another post, they don't even "have" to release all of the OS code.

There's tons of source code they've released that they didn't have to: clang ...

...XNU, the C library, a bunch of kernel extensions, and so on.

Comment Re:How easy is it to fix something yourself? (Score 1) 134

The other side of this is that Linux developers can use it to gain insight to making your favorite Linux distribution run – or run better – on Mac hardware.

...assuming that the code to support the Mac hardware in question is in the kernel, or an open-source kernel extension ("loadable kernel module" in Linux-speak), rather than in a non-open-source kernel extension.

Comment Re:OSX is BSD Unix with Some Extras (Score 1) 134

Understand that the MacBook OS is a BSD kernel

Well, Mach+BSD, but both are open source.

the GNU OS (tool chain)

Some of userland is GNU (and some of it may be GNU in various of the *BSDs). Other parts of userland are also from BSD, or written by Apple, or code from various other places. The toolchain, if by that you mean "the compilers, the assembler, and the linker", aren't GNU any more or were never GNU. The assembler and links are from Apple (some possibly ultimately from NeXT); the compilers used to be from GNU, but they're now from the LLVM project.

Comment Re:huh (Score 5, Informative) 134

Like they've done with every version? Of course it's only the code they have to release.

Not true. They don't have to release a lot of it; for example, the XNU kernel is licensed under BSD licenses, the BSDish license under which Mach was released, or the APSL, none of which oblige Apple to release any of it.

Comment Re:Time Capsule (Score 1) 238

You cannot back up files on a HFS disk without losing unix permissions. HFS, NTFS, EXT4 or almost any other file system would work.

Sentence 1 says HFS won't work. Sentence 2 says it will work. In which of those sentences should "HFS" have been something else, and what should it have been in that sentence?

Comment Re: I was born with the microprocessor (Score 1) 74

Could but usually doesn't. As the hardware was more costly and slower, and labor relatively cheaper, mainframes ran in some sense "better" code with far less bloat and frillage. An A was just an A (ascii or baudot or ebcdic) - not a picture of a letter in some font taking many times the bits to store and draw for just one example. Audio or video which were (And still are) largely irreducible to small bits/second were right out for real time use. Mainframes had "acceleration" hardware to compensate. Line printers took a few bits and did the drawing parts (as did plotters for other uses).

The old line printers didn't do any drawing of pixels, they just had a hammer slam a piece of metal, with a character formed on it, against a ribbon, hitting a piece of paper. The laser printers like the IBM 3800 just let the processor in the printer draw all those bits, rather than doing it in the main CPU.

(And, in a file, an A is still just an A, these days - although if it's UTF-16, it's two bytes rather than one. Those pictures aren't stored in most documents.)

Comment Re:I was born with the microprocessor (Score 1) 74

Our computers are not descendants of the mainframes that came before them. By now, they have acquired many of the advanced features of mainframes. Implemented badly, several decades later. It is fascinating to learn about the history of mainframes. It is also somewhat depressing.

And sometimes it goes the other way; the IBM z13 microprocessor cracks z/Architecture instructions into micro-ops and schedules and executes the micro-ops, just as the Pentium Pro and later x86 microprocessors do.

But you're probably referring to system architecture characteristics, in addition to CPU characteristics.

(Speaking of system architecture characteristics, the z13 has I/O instructions to bang on PCI space, so you could plug PCI devices in and have minicomputer/microcomputer-style drivers, rather than doing I/O over a traditional data channel. They're not documented in the Principles of Operation, but they're used in some of the Linux code for z/Architecture.)

Comment Re: NASA Eagleworks is NOT NASA! (Score 3, Informative) 711

They are directly related. https://ntrs.nasa.gov/search.j...

As the NASA document you cite (HTML FTW!) says, it's "an advanced propulsion physics laboratory, informally known as "Eagleworks"" being implemented by NASA Johnson Space Center (NASA/JSC), so it is part of NASA.

Comment Re:Touch Bar Escape Key? (Score 1) 361

Is this where the fabled escape key has been banished to?

Yes - there were several scenes in the video of the Apple event showing a virtual key labeled "esc" on the left-hand edge of the touch bar (although, as I've noted elsewhere, it's not directly above the {~ `} key, which may get in the way of muscle memory).

Comment Re:No escape (Score 1) 361

And I don't see an escape key. :(

I guess you didn't watch the video of the Apple event, where the touch bar had, in many scenes, a button on the left hand edge marked "esc". (As I said in comments for the rumor article, it's not directly above the {~ `} key, so your muscle memory may have some issues with it.)

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