JdeBP

8 ms·

91.
by JdeBP 4mo ago
That's not really an explanation of why the people who have made synthesizable 8086/8086 processors haven't done the same thing for the 8087, because modern FPGAs aren't limited by the cutting edge of 1980 technology. (
92.
by JdeBP 4mo ago
And largely irrelevant if the goal is synthesizing something that can be put onto an FPGA to be a workalike for the 8087. It's almost never about synthesizing the exact original hardware to be fabricated. See CPU86 and Zet, for examp
93.
by JdeBP 4mo ago
The adder is not clocked. You can see from the diagrams that there are no clock inputs. The clock cycles comment is more an expression of the length of time that it takes before all of the carry rippling and whatnot settles down.
94.
by JdeBP 4mo ago
It is interesting that over the years people have produced synthesizable RTL HDL for the 8086/8088 and later, with varying degrees of fidelity, but no-one seems to have produced similar for the 8087.
95.
by JdeBP 4mo ago
Yes there should, and the maximum size of what fits into a 512-octet DNS/UDP query packet, less header and EDNS0 and whatnot, is going to be that limit, ultimately. Because SMTP-based Internet MTSes that do not look up MX resource rec
96.
by JdeBP 4mo ago
Actually, there are a number of full-screen editors that pre-dated vi. They were for mainframe operating systems, or were confined to some university or other, or were commercial products for something like CP/M made by some tiny comp
97.
by JdeBP 4mo ago
I tend to go for keyboards that don't need all of that messing about with the Fn key, too. By the way: It's a lot more than 100 keys. People tend to accept that because they have what is called a '105-key' keyboard th
98.
by JdeBP 4mo ago
I agree about the special keys. There are so many HID usages on the Consumer page for keyboards covering so many things, from application launchers to extra editing functions, and it is absurd how often almost none of them are used in favo
99.
by JdeBP 4mo ago
I'm surprised that this has not triggered all of the reminiscences of sitting running mailq at intervals for hours to watch mail that hasn't even left the local sending machine yet .
100.
by JdeBP 4mo ago
Realistically, the length of the domain part is likely ultimately constrained by how large a domain name can fit into a DNS/UDP query packet (alongside EDNS0).
101.
by JdeBP 4mo ago
Even that's not the true length limit of a label in the Domain Name System. (RFC 1034 § 3, for the curious.) So someone is likely going to be fixing that, years down the line. Then of course there's the fact, as called out earl
102.
by JdeBP 4mo ago
These seem related: * https://news.ycombinator.com/item?id=48418318 ( The Blight Reaches Microsoft: 73 Repos Disabled in 105 Seconds ) * https://news.ycombinator.com/item?id=48450543 ( Miasma Worm Hits Micr
103.
by JdeBP 4mo ago
> I do not use a graphics driver. Yes you do. It's the one that your in-kernel terminal emulator talks to in order to splat its bitmap fonts onto the screen. It is whatever wsdisplay has attached to, which can be one of a range of
104.
by JdeBP 4mo ago
From inspection of the code: If you have the files in the XDG locations and symbolic links in the old locations, this migration mechanism will mess things up quite badly, because it does not check for either symbolic or normal links and ren
105.
by JdeBP 4mo ago
> Thus I don't use a terminal emulator. Yes you do. It's the one built into your operating system's kernel. You'll find a lot of, but not all of, its code in /usr/src/sys/dev/wscons .
106.
by JdeBP 4mo ago
Maybe, but notice that almost all of the article, and its followup posted today, is about the speed of starting a shell not of a terminal emulator window . So if you use interactive sub-shells, anything from shelling out of a vi clone o
107.
by JdeBP 4mo ago
My guess is that it was undocumented until Release 3 or 4, so the book authors simply never found out about it. Andrew Tanenbaum knew about it at the same time as the first Hunter and Fielding book, but likely this was word-of-mouth stuff.
108.
by JdeBP 4mo ago
You can even tell which operating systems xe has used. Both of those are very specific. The \FOUND.nnn directories are something that IBM/Microsoft introduced when they re-did CHKDSK for OS/2, which was what Windows NT inherited
109.
by JdeBP 4mo ago
Chicken and egg problem. On the UFS and suchlike filesystems, at the point that fsck is rescuing orphaned i-nodes, it still has not fully gone through the process of checking and correcting free list information, or indeed fully eliminating
110.
by JdeBP 4mo ago
It did. Foxley gives the manual procedure for sizing the lost+found directory on the aforementioned page 52. I have the 1986 edition of Fielder's and Hunter's UNIX System Administration and it does not mention any such command i
111.
by JdeBP 4mo ago
I recommend starting with ECMA-35. The actual structure of escape sequences is explained there. Otherwise it gets lost that it's the ESC [ that is the entire escape sequence , an alternative form of CSI, and that this actually is on
112.
by JdeBP 4mo ago
I have a book on my bookshelf, Eric Foxley's Unix for Super-Users . It was published in 1985, and it answers this question on page 52, the first page listed for the entry 'lost+found' in its index. This is surely not the ea
113.
by JdeBP 4mo ago
It is StackExchange. So in theory someone could modernize it at any time.
114.
by JdeBP 4mo ago
That's what the answers are missing, of course. In some filesystem formats, it's possible either to recover completely from a journal/intent log, or at least to recover everything to the point that recovered files can be pla
115.
by JdeBP 4mo ago
Yes, outwith the idea of Family API programs (which couldn't use Presentation Manager and whatnot anyway) OS/2 1.x did target the 286 as a minimum. But that doesn't mean that DOS+Windows didn't use the features. It did.
116.
by JdeBP 4mo ago
It wasn't really the processor architecture. Segmented addressing was actually fairly easy if the processor was used only in the way that protected mode was envisioned as working. As the headlined article observes, a lot of this st
117.
by JdeBP 4mo ago
It wasn't really the 'Undocumented' and 'Internals' books. Pretty much everything in the headlined article was to be found in the SDK, Microsoft Press publications, and in many third party books about DOS+Windows p
118.
by JdeBP 4mo ago
Check the ID numbers (48410844 < 48424862) and bear in mind that Hacker News has this thing where sometimes submissions get re-cycled for attention. Yes, annoyingly it does seem to make the presented datestamps wrong.
119.
by JdeBP 4mo ago
Psst! Let's blow their minds and tell them about the MC68008. (-:
120.
by JdeBP 4mo ago
It's a fairly widespread idea for architectures that try to move things out of kernel mode. The Hurd does program image file loading in userspace, too, in its exec server(s). The tricky part is setting up the initial process. The way

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