78

You are comparing apples to motorcycles. Windows 95 traces its lineage back through Windows 3.x all the way to Windows 1.x and MS-DOS/PC-DOS, themselves inspired by CP/M. It was conceived and designed as a single-user, cooperatively multitasking environment in which applications have a large degree of freedom in what to do. Windows 95 moved towards a ...


72

The short version is that Windows became the de facto operating system thanks to Microsoft’s business acumen (or shenanigans, depending on your point of view), marketing, skilled developers, a strong focus on backwards-compatibility, and the success of MS-DOS. The success of Windows in general can be traced back to the success of Windows 3.0, which has ...


54

The I/O model on "Cutler systems" -- RSX-11M, VAX/VMS, Windows NT -- is an asynchronous packet-driven I/O model, rather than the fundamentally synchronous I/O model of Unix. At its core, you fire off an I/O request, and get a notification of when it's complete. Meanwhile, execution continues. Of course, it's trivial for the system to provide synchronous I/...


51

DOS/360 (As distinct from TOS/360, the tape OS) Announced at the end of 1964 per Wikipedia.


37

The decision about whether to kill a process or crash the OS generally depends on whether the problem can be isolated to the process. For example, if a running process in user mode attempts to read from an address that's not present in its address space, that's not going to affect anything else. The process can be terminated cleanly. At the other extreme, ...


33

The simple answer is that early operating systems for the systems you mention did not provide those features. Apple DOS, for example, makes no use of interrupts, and has no concept of processes or memory protection. Nor does DOS have any concept of hardware drivers, as it includes support to drive the Disk II (a deep assumption in DOS) and nothing else. ...


32

The other answers include a lot of sound historical information about how Windows evolved into its dominant role on PC's in both the home and business environment. But I think the most fundamental, simplest, "Occam's razor" answer is that consumers never had to make a choice. It was PC manufacturers that chose Windows as the default OS, not users and ...


28

For "home" computer systems such as the Apple II, the "operating system" wasn't anything like a modern one with processes and device drivers and so on; by the standards of modern OSes there wasn't really one at all. As a warning: all these explanations (long as they are) are for the most part considerably simplified. This answer is ...


21

While I am sure that the merits of Cutler's stated "low opinion" could be debated, I'm interested to better understand exactly what he was referring to here. There's no citation, and I haven't found a good explanation critiquing his criticism. Honestly, at face value, it's a naive criticism. Cutler was not naive, so, it's likely just a sound bite poke ...


18

At the operating system level – as seen by applications – files in VMS are very record oriented. Guide to OpenVMS File Applications (336 page, 2MB PDF) probably goes into far more detail than anyone should be expected to know, but you can get a feel from the Introduction (emphasis mine): 1.1 File Concepts A computer file is an organized collection of ...


17

We talk about the late 1970s and mainstream 6502 machines, right? It wasn't so much that programs run under OS control as that OS was a support function to Programs. More like what we would today see as a standard library with routines supporting simple I/O abstraction plus basic file handling on the user side and hard coded drivers within. Some, like ...


15

How exactly did Windows become the OS of the home PC? Is it true that the Windows OS, at it's core was originally designed to simply be the OS of the terminals of the windows server architecture. No. Windows started out as a GUI component of DOS - eventually hiding DOS beneath. Anything like a windows server architecture was only devloped way later. In ...


12

The typical circa-1980 8-bit CPU provided almost no support for modern operating system features. It was often possible to add such support using external logic, but very few machines actually did so because it would have added costs to the hardware with little practical benefit. Even many minicomputers of the time left those features out, at least in the ...


11

Although Windows 95 introduced support for 32 bit applications with memory protection, it was still somewhat reliant on MS DOS. For example, where native 32 bit drivers were not available, it used 16 bit DOS drivers instead. Even 32 bit applications had to be synchronized with the 16 bit DOS environment. A fault in the DOS part of the system would bring the ...


11

Note: this is mostly guesswork I don't know this assembler but the f suffix seems to denote a label. Example bec 1f jmp cerror 1: Those instructions write the parameters in the parameter zone of the system call. mov 6(r5),0f mov 8(r5),0f+2 note that there's a 0 label just after the sys instruction. It holds the parameters (copies of those which ...


10

Contemporary operating systems for the 6502 did not have those features. But not because they couldn't. It just wasn't considered necessary or desirable. Provide automatic switching between processes. The standard trick here is to have a clock attached to an interrupt that the OS can use to perform a context switch. This seems doable on the 6502 with ...


10

The PDP-8 is a 12-bit computer.  As such it has a word and pointer size of 12-bits — meaning it can access 4k words using a single word pointer. Later models added bank switching (KM8E) and 3 extra address lines so that up to 32k words (8x4k) words could be populated, now having 15 address lines.  (Core memory boards, 4k words each, you ...


9

RSTS-11 (not RSTS/E) ran on the 11/20. It offered multiuser timesharing in BASIC. I think that in addition to the base 11/20 hardware, you needed a clock. You needed to max out the memory (28 Kwords). V4 was the last RSTS-11 release before it became RSTS/E. System manager's manual for RSTS-11. I have not checked to see if there are software kits available....


8

RISC OS Pico on the Raspberry Pi boots to BASIC. See https://www.riscosopen.org/content/downloads/raspberry-pi The "full fat" RISC OS could also be made to boot to BASIC using *CONFIGURE commands like you can with the Archimedes and RISC PC. Note that riscosopen.org do not list the RasPi4 as being compatible (and RISC OS Pico has a smaller compatibility ...


7

ToolShed seems to be the current maintained OS9/descendants disk manager tool. It's not a file browser but works on the command line. Are you sure your disk image is a valid RBF image, though? Toolshed refuses to read it: $ os9 dir os9000-xibase.img dir: error 216 opening 'os9000-xibase.img,' dir: error 216 opening 'os9000-xibase.img' Similarly, checking ...


7

The BC-7 had a SQL like query language called ESCORT. You could indeed write a simple query in this manner: SELECT * FROM FILENAME OUTPUT TO PRINTER [] and this would dump the contents of a file.


7

At that time, computing model was very rich API, complex CPUs, complex tools, etc. Filesystem were almost structured files oriented, etc. UNIX came with its "uniform" vision of I/O, everything is a file, a file is just a stream of bytes. That wasn't so easy for people trained on former OSes to understand why UNIX is a good model. While I loosely remember the ...


7

Manchester MUSS ran on a PDP11/10, but I can't offer a working PDP11 image for it at the moment as it is lost in passage of time.... It would have been able to do its own memory management and swap, multitasking etc.


6

From what I can see, it probably never got beyond a very basic system running only on the 68000. Jerry Pournelle's last comment on it in April 1985 BYTE (p.361) covers his experience with it before the November 1984 COMDEX show: Frankly, [S1] sounded like a scam, and my views weren't changed when I found an MSI booth at a show last year and was told ...


6

The history of windows goes back a long way. Windows 1.0 was released in 1985 and was simply a graphical interface for MS-DOS. This was neither revolutionary nor uniquely Microsoft, but a trend at that time. For example, GEOS appeared in 1986 and was the same thing for the C64. There was also GEM and a couple others. Since the development times on these ...


6

So bare metal, no OS? On both systems, console terminal I/O is considerably easier than any other terminal interface. On many VAXen, there's a couple of processor registers that are status and data registers for console I/O. Much easier than dealing with DZ-11 or similar. Here's the important part of a VAX 'putchar' routine from a standalone libc I wrote in ...


5

Ignoring MS-Net, Microsoft has marketed server systems since 1987: first LAN Manager, based on OS/2, then in 1993 Windows NT 3.1 Advanced Server, and then the various Server editions of successive Windows NT and Windows 2000 releases, which gave way to Windows Server. MS-DOS 3.1 and later, and all versions of Windows, have been able to integrate with these ...


5

Background: Windows NT was the basis for all Microsoft Windows "Server" Operating Systems that had that name. Previous iterations of MS networking products were mostly add-on device drivers for simple file sharing. There was also the complete line of Windows Desktop OS's from Windows 1 through Windows Me that were marketed for both home and business use. The ...


5

DOS-ordered images were created by DOS programs that started reading from track 0 sector 0, continued to sector 15, moved to track 1 sector 0, and so on until the end of the disk. They are in DOS logical order: the first 256 bytes are T0S0, the next are T0S1, and so on. ProDOS-ordered images are created by ProDOS programs that started reading from block 0, ...


5

Not an answer, as Jean-François Fabre has already deducted all workings, but some hints about the syntax/workings of AS to understand the source. This source is meant to be assembled using the Unix assember AS. AS is an extreme primitive assembler designed only to handle machine specific parts of Unix. It carries only the most essential functions and those ...


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