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trigglux@trigglux
September 19, 2022

I got a mad idea, and I blame DOS week for. The background for this is special_snowflake, the FOSH computer I've been building/writing for the last 5 years. Without going into all the details (because then I'll be here for two days), its new CPU is registerless and directly reads and writes into main memory for all instructions. To make it performant, the "main memory" is 0.5-8 KiB is size and treats the actual RAM as expanded memory, copying bits of it in and out. Like a disk. Now, that leaves me with the question of organization of this expanded memory. I decided I won't go the normal route and I won't implement a virtual memory system. Which leaves me with the question of what to do.

And then it occured to me yesterday. What IF you treated your expanded memory as a literral disk and put FAT on it? To allocate memory, processes create a file of some size. Processes can pass memory objects to each other by passing filesystems paths around. All memory objects are dynamically sized. Some implementations of FAT (DR-DOS 6.0 and others) track user&group ID as well as access permissions for them. You could literally implement the well-understood-by-sysadmins Unix filesystem permissions model for all memory! Super important: a single categorization unites ALL of memory which means ALL of memory is always accounted for. Modern systems have all kinds of weird kinks. Inodes, sysfs, procfs, netlink, ioctl, device nodes, semaphores, muliple kinds of sockets, multiple namespaces for all those kinds of sockets, acl, quotas, memory maps, process trees, uids and guids, mounts, etc, etc... If you put all of those into a filesystem, you suddenly make them all observable and manipulable. Another benefit: it's now possible to dump the entire contents of memory to real disks and examine them or change them. Messing with system internals is now easier than ever! And the best part? Both the running memory and the disk image of it can be manipulated with normal filesystem tools!

This can be made to play real nice in a microkernel design with lots of system daemons offering services. I already checked the extensive Wikipedia article on FAT and I found that it practically nativelly supports being used for this purpose. You would need to repurpose some fields from what Microsoft uses them for, but this is a long and time-honoured tradition. The article (linked below) lists several mutually incompatible standards for various data structures that were all used in parallel by several operating systems from several vendors.

Besides breaking the Microsoft's non-standard on FAT, there are two other problems I can see. The first is that my CPU is big-endian and FAT is used on little-endian machines which means the multi-octet fields will be messed up. That can be lived with - this will only come into effect if somebody attempted to mount the memory image on a little-endian machine, but that can be fixed by the appropriate filesystem driver.

The much bigger problem - and the only serious problem I've so far seen - is that FAT keeps track of file contents in a singly linked list. That's.... inapropriate for quick access. :) Since the use of this scheme implies there is only one daemon which manages the memory filesystem for all other applications, and since this is the only place where file handles (or whatever) is handed out, this limitation can be worked around. The filesystem daemon could keep a special structure for all open files/assigned file handles which has a map to all clusters that are part of the file. So if you want to randomly access parts of a large file, the FS daemon doesn't have to read the entire FAT from the start, it can just read from its map. But the problem is that, since this is a memory management scheme, most files can be expected to be open. Which would mean most files would have an associated fast-access map. But then the question is why have the FAT, if most access is going through the map?

Another mitigation strategy is to take care to have the memory defragmented, and then try to assign memory in large contiguous blocks of clusters. That way, if the random access happens inside such a large block, working out the sector (=page) that is to be accessed should be straightforward. The access map cache from the previous paragraph then only needs to keep track of starts and lenghts of blocks. The scheme is simpler, requires less overhead, and should benefit from the last four decades (!) of improvements to FAT drivers and algorithms.

This manage-memory-as-a-filesystem idea can BTW also be implemented on normal registered CPUs, by having some pages (in the reserved section between the sector 0 and the first FAT table xD ) function as faux main memory for currently running processes and the rest used in the FAT.

Wikipedia page on FAT: https://en.wikipedia.org/wiki/Design_of_the_FAT_file_system

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Bryan Lunduke@Lunduke
21 hours ago
Linux Foundation's Mandatory DEI Training

Lunduke takes the "Inclusive Open Source Community Orientation" certification, which focuses on BLM, Pronouns, Critical Race Theory, Micro-Inequities, and DEl.

That's right. Lunduke is now "DEI Certified" by The Linux Foundation.

00:32:23
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Bryan Lunduke@Lunduke
January 20, 2025
Linux Distro Declared "Non-Woke", Causing New Users & Interest to Skyrocket

While "Woke" Linux Distributions (like openSUSE) are struggling to survive, interest in OpenMandriva - a non-Woke Open Source project - is exploding.

00:29:15
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Bryan Lunduke@Lunduke
January 19, 2025
Godot Game Engine Went Woke... And Lost $160,000 Per Year.

A few months ago, the Open Source Godot Game Engine enacted a mass "cleansing" of Non-Woke supporters. Then their monthly donations dropped by over 25%.

00:10:46
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Bryan Lunduke@Lunduke
November 22, 2023
The futility of Ad-Blockers

Ads are filling the entirety of the Web -- websites, podcasts, YouTube videos, etc. -- at an increasing rate. Prices for those ad placements are plummeting. Consumers are desperate to use ad-blockers to make the web palatable. Google (and others) are desperate to break and block ad-blockers. All of which results in... more ads and lower pay for creators.

It's a fascinatingly annoying cycle. And there's only one viable way out of it.

Looking for the Podcast RSS feed or other links? Check here:
https://lunduke.locals.com/post/4619051/lunduke-journal-link-central-tm

Give the gift of The Lunduke Journal:
https://lunduke.locals.com/post/4898317/give-the-gift-of-the-lunduke-journal

The futility of Ad-Blockers
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Bryan Lunduke@Lunduke
November 21, 2023
openSUSE says "No Lunduke allowed!"

Those in power with openSUSE make it clear they will not allow me anywhere near anything related to the openSUSE project. Ever. For any reason.

Well, that settles that, then! Guess I won't be contributing to openSUSE! 🤣

Looking for the Podcast RSS feed or other links?
https://lunduke.locals.com/post/4619051/lunduke-journal-link-central-tm

Give the gift of The Lunduke Journal:
https://lunduke.locals.com/post/4898317/give-the-gift-of-the-lunduke-journal

openSUSE says "No Lunduke allowed!"
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Bryan Lunduke@Lunduke
September 13, 2023
"Andreas Kling creator of Serenity OS & Ladybird Web Browser" - Lunduke’s Big Tech Show - September 13th, 2023 - Ep 044

This episode is free for all to enjoy and share.

Be sure to subscribe here at Lunduke.Locals.com to get all shows & articles (including interviews with other amazing nerds).

"Andreas Kling creator of Serenity OS & Ladybird Web Browser" - Lunduke’s Big Tech Show - September 13th, 2023 - Ep 044
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ArchieT@ArchieT
3 hours ago

a funny mistake I made today... :)
( I'm so meta )

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Dan "The OG RetroPunk"@retropunk
2 hours ago

Where there's a will, there's a way... I just got a report about a student who used the built-in Copilot functionality in Edge as a proxy to bypass the school's content filter to play some crummy looking flash-like game. Our filters are pretty thorough and all of the well known (and frankly most of the lesser known) proxy sites are blocked. I'm not supposed to approve of this behavior, but the nerdy side of me is genuinely impressed how many ways these kids can find to make things work.

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fossman@Fossman
4 hours ago

https://www.bleepingcomputer.com/news/technology/brave-search-now-lets-users-rerank-results-from-favorite-sites/

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Bryan Lunduke@Lunduke
January 13, 2025
Last 24 Hours: 55% off DRM-Free MP4s, & Discounted Lifetime Subscriptions

Holy guacamole, Batman! We are now over 80% of the way to our funding goal… for the end of February. And it’s not even half way through January! I am absolutely gobsmacked.

Want to help push us over the 100% line — and directly fund the truly independent Tech Journalism of The Lunduke Journal?

Lots of options. Big and small (and all amazingly helpful). Scroll down & choose whatever works best for you.

Lunduke Journal Discounts

For the next 24-sh hours (through Tuesday, January 14th), in addition to regular subscriptions, you can grab two limited discounts:

  1. Discounted Lifetime Subscriptions (details below)

  2. DRM-Free, MP4 Downloads for 2024 & 2025 (combined) for 55% off.

There many ways to support The Lunduke Journal. Choose the option that makes you smile. It’s all listed below.

Where to grab a Monthly or Yearly Subscription:

Lifetime Subscription Details:

  • Pay once, full subscription for life (on Locals, Substack, or both).

  • Available only through Tuesday, January 14th. Then the Lifetime Subscription option goes “back in the vault”.

  • Can be purchased via Locals, Substack, or with Bitcoin. Scroll down for steps.

Where to buy a DRM-Free, MP4 video yearly download pass:

Want to be able to download every show The Lunduke Journal releases (and watch them on whatever device you like)? Yeah. You can do that.

The Famous Lifetime Subscription via Locals

The "World Famous Lunduke Journal Lifetime Subscription" is exactly what it sounds like. Pay once and get full access to The Lunduke Journal (with all the perks of subscription on Locals). For life.

New Lifetime Subscriptions are available, for $200, from now through January 14th. Then this option goes "back into the vault".

Here's how to grab one of these coveted bad boys for yourself:

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  1. Go to Lunduke.Substack.com/subscribe.

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If you would like full, Lifetime access to Lunduke.Locals.com (which is included):

  1. Make a free account on Lunduke.Locals.com.

  2. Email “bryan at lunduke.com” with the email address you use on both Substack and Locals (can be different email addresses).

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The Famous Lifetime Subscription (with Bitcoin discount)

And, finally, you can obtain a Lifetime Subscription via Bitcoin. Save a few bucks with this option, as Bitcoin processing has fewer fees associated with it.

  • Make sure you have a Lunduke.Locals.com account (a free account works just fine).

  • Send $190 worth of Bitcoin (or more) to the following address:

bc1qyjakve8fywm8pz2v99v57yhjj0vzr2vjze6fcq

  • Email "bryan at lunduke.com" with the following information: What time you made the transaction, how much was sent (in Bitcoin), and the email address you use (or plan to use) on Locals.com.

Nice and easy. Lots of options.

Once again, thank you. The Lunduke Journal would not be possible without your support.

You rule.

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Bryan Lunduke@Lunduke
January 12, 2025
Discounted Lifetime Subs, 55% Discount on MP4 Downloads for 2 Days

The Lunduke Journal remains 100% free from advertising… and, even more importantly, 100% free from all Big Tech influence.

And, because we never take a penny from any company, this is only possible thanks to you.

All of you amazing nerds showed tremendous support for The Lunduke Journal last month — grabbing Lifetime and standard subscriptions — meeting our necessary funding requirements for January… before January even started.

Mind. Blown.

This allows me to focus on new reporting — without needing to worry so much about funding and “business stuff” during the month. Which means more shows & more investigations. A massive win for all of us.

That also means that, this month, we don’t need to do a big “fundraiser”. Instead, we’re going to just send out this quick reminder of how absolutely critical your support is for the continued success The Lunduke Journal — the last bastion of truly independent Tech Journalism.

Seriously. Couldn’t do this without you.

Scroll down and take a look at the options. See if any jump out at you. Then give yourself a high five for making Tech Journalism that much more awesome.

Lunduke Journal Discounts

For the next 2 days (through Wednesday, January 15th), in addition to regular subscriptions, you can grab two limited discounts:

  1. Discounted Lifetime Subscriptions (details below)

  2. DRM-Free, MP4 Downloads for 2024 & 2025 (combined) for 55% off.

There many ways to support The Lunduke Journal. Choose the option that makes you smile. It’s all listed below.

Where to grab a Monthly or Yearly Subscription:

Lifetime Subscription Details:

  • Pay once, full subscription for life (on Locals, Substack, or both).

  • Available only until Wednesday, January 15th. Then the Lifetime Subscription option goes “back in the vault”.

  • Can be purchased via Locals, Substack, or with Bitcoin. Scroll down for steps.

Where to buy a DRM-Free, MP4 video yearly download pass:

Want to be able to download every show The Lunduke Journal releases (and watch them on whatever device you like)? Yeah. You can do that.

The Famous Lifetime Subscription via Locals

The "World Famous Lunduke Journal Lifetime Subscription" is exactly what it sounds like. Pay once and get full access to The Lunduke Journal (with all the perks of subscription on Locals). For life.

New Lifetime Subscriptions are available, for $200, from now through January 15th. Then this option goes "back into the vault".

Here's how to grab one of these coveted bad boys for yourself:

  1. Go to Lunduke.Locals.com/support.

  2. Select "Give Once".

  3. Enter "200" into the amount field.

  4. After checking out, Lunduke will toss you an email once your account is set to full lifetime status. (This usually happens within a few hours.)

The Famous Lifetime Subscription via Substack

You can also snag a Lifetime Subscription via Substack:

  1. Go to Lunduke.Substack.com/subscribe.

  2. Select the “Lifetime Subscription” option.

  3. After checking out, Lunduke will toss you an email once your account is set to full lifetime status. (This usually happens within a few hours.)

If you would like full, Lifetime access to Lunduke.Locals.com (which is included):

  1. Make a free account on Lunduke.Locals.com.

  2. Email “bryan at lunduke.com” with the email address you use on both Substack and Locals (can be different email addresses).

  3. Lunduke will toss you an email once your account is set to full lifetime status on Locals.

The Famous Lifetime Subscription (with Bitcoin discount)

And, finally, you can obtain a Lifetime Subscription via Bitcoin. Save a few bucks with this option, as Bitcoin processing has fewer fees associated with it.

  • Make sure you have a Lunduke.Locals.com account (a free account works just fine).

  • Send $190 worth of Bitcoin (or more) to the following address:

bc1qyjakve8fywm8pz2v99v57yhjj0vzr2vjze6fcq

  • Email "bryan at lunduke.com" with the following information: What time you made the transaction, how much was sent (in Bitcoin), and the email address you use (or plan to use) on Locals.com.

Nice and easy.

Once again, thank you. The Lunduke Journal would not be possible without your support.

You rule.

-Lunduke

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Bryan Lunduke@Lunduke
January 09, 2025
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The House of Lunduke BBS
Telnet: BBS.LUNDUKE.COM

The House of Lunduke BBS is a 20 node, Telnet BBS (bbs.lunduke.com) focused on the golden age of DOS BBS gaming -- including TradeWars 2002 and Legend of the Red Dragon.

 

 

The BBS is free to use, & creating an account takes only a moment.  All new users are granted 2 hours of access to all games on the system (more than enough to get in your daily turns of every one of these classic games).

Current games on the BBS:

  • TradeWars 2002 (aka TW2002)
  • Legend of the Red Dragon (aka LORD)
  • Legend of the Red Dragon 2
  • The Pit
  • Exitilus
  • DoorMUD
  • Barren Realms Elite

 

How to Connect

 

Accessing The House of Lunduke BBS is incredibly easy.  Simply point any Telnet client at "bbs.lunduke.com" on port 23 (the default Telnet port).

This means, on many systems, a simple:

telnet bbs.lunduke.com

Will, technically, work.

However, if you want to have the absolute best experience -- and see what BBSing was truly like back in the 1980s and 1990s -- you'll want to use a Telnet client capable of displaying ANSI color... specifically one tuned for BBSes.

The following Telnet clients are all recommended and work well with The House of Lunduke:

Once you have chosen your Telnet client, simply add "bbs.lunduke.com" to your address book and connect.  Or, from within some Telnet clients, you can also type "atdtbbs.lunduke.com" (no spaces).

Fun fact: "ATDT" is a command which tells an old-school modem to "tone dial this number".  The "AT" stands for "Attention", "D" stands for "Dial", and ending T stands for "Tone".  In the old days ATDT would be followed by a phone number... but, since we're connecting via Telnet, we now use a domain.

Or, if you want to get really old-school, it is possible to utilize DOSBox and an era appropriate terminal client (such as Telemate).

 

 

F.A.Q.

 

Q: What software does The House of Lunduke BBS run?

A: The core BBS software is known as Virtual Advanced (a successor to VBBS), a DOS-based BBS package that acheived some popularity during the early 1990s.  All of the games on the system (known as "Door games" in BBS terminology) also run on DOS -- and each is the most popular version (or the last version) of each.  A Telnet server handles incoming telnet connections -- which then interfaces with the DOS-based BBS software, using what is known as a FOSSIL driver.

 

Fun Fact: A FOSSIL driver is a serial interface driver -- which makes it easier to use a standard interface to multiple different communication devices (such as a type of dial-up modem or a Telnet connection).  FOSSIL stands for "Fido Opus SEAdog Standard Interface Layer".  Which is a fun name.

 

Q: What does "20 node" mean?

A: In "ye olden times", BBSes used modems and phone lines.  One person, at a time, could call a BBS on each phone line.  Each of these is a "node".  We are now living in the future -- and using Telnet instead of phone lines -- which means that, in theory, we could have a small mountain of people connecting at the same time.  However.  Since we are using 1980s and 1990s DOS software, jury-rigged to work with the modern Internet, some of those old limitations still apply.  20 nodes were chosen as that makes for an incredibly large BBS system... but not too difficult to manage.

 

Q: Why not use a more modern BBS server?

A: There are several "modern" BBS servers -- with many fancy benefits.  MysticBBS, Synchronet, and others.  The House of Lunduke BBS is not about being modern.  Or fancy.  It is about preserving a snapshot of a high-point in BBS gaming history.

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