In case you have DOS installed on the hard drive, you can also use GRUB4DOS [1] - just put gentleos.elf on C:\, run grub.exe, then `kernel /gentleos.elf`. You may first need to comment out any upper memory managers from config.sys. A bit of an academic exercise since the kernel still won't fit into memory.

Btw. feel free to reach out to me on my profile email. I'll be busy with work for the rest of the week, but later I may look for some workarounds to get it running on 2 megs.

[1] https://sourceforge.net/projects/grub4dos/

> - noticed krn_main() ends with `while (1);` [1]. I would've expected a "schedule" call or something. I assume there's no real busy loop burning CPU, maybe it's never meant to reach this code?

Yeah, `gui_main()` takes over and is not supposed to return, so the code is unreachable. The loop is just an old idiom used in such places (e.g. [1]), though I've now replaced it with a comment and a call to `halt()` to better convey the intention.

> - I'm reminded of the "bare metal OS" when I see one of the apps call `krn_*` functions directly [2].

Yeah... but at least the kernel doesn't call the apps... which it could ;^)

[1] https://github.com/freebsd/freebsd-src/blob/main/sys/x86/x86...

Btw. the QEMU screenshots are still in the repo in https://github.com/luke8086/gentleos32/tree/main/doc/appimg

- Letting it warm for a while

- Putting windows in the right places, because each one generates its own artifacts

- Setting background to dark with the white pattern

- Fiddling with the contrast knob and matching it with the right viewing angle

- Using 2x zoom

To be fair, the default photo app of iPhone 16 automatically reduced some of the artifacts. The only post-processing done myself in GIMP was very basic stuff like adjusting white balance, exposure and contrast.

Here you can see a few very quick-n-dirty photos I just took for comparison - https://imgur.com/a/6Xz6vc8

It only won't work on modern pure-UEFI systems because that would require writing full stack of USB drivers for keyboard and mouse, and that would be a huge task.

I've been working on a simple OS for tinkering and running bare metal apps on vintage PCs.

Since I couldn't quite decide whether to target pure 16-bit, or slightly more capable 32-bit machines, I ended up with two separate versions:

- GentleOS/32 (https://github.com/luke8086/gentleos32) works on i386+, requires 4MB of RAM and VGA display supporting 640x480x16 mode or any 256-color VESA mode.

- GentleOS/16 (https://github.com/luke8086/gentleos) works on 80186+, requires less than 192KB of RAM and a CGA display supporting 320x200x4 mode.

You can find more details in the repos.

Comments URL: https://news.ycombinator.com/item?id=48435943

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For example, for many years the FreeBSD's 3rd-stage loader used FICL (Forth Inspired Command Language) for scripting [1]. It's still supported, although in the recent years it was deprecated in favor of Lua [2].

[1] https://github.com/freebsd/freebsd-src/tree/main/stand/forth

[2] https://github.com/freebsd/freebsd-src/tree/main/stand/lua

  $ ls -1 fixgui_\*.c
  fixgui_cocoa.c
  fixgui_gtk.c
  fixgui_haiku.c
  fixgui_win32.c

Sometimes it's on, see https://ftp.netbsd.org/pub/NetBSD/NetBSD-release-10/src/etc/...

> By default only one tty is enabled

Ah, but the rest is getting enabled by the installer, see https://github.com/NetBSD/src/blob/netbsd-10/usr.sbin/sysins...

> NetBSD might have some "bloatware" but _the user must enable it_ first

> Everything is off by default. That is one of the things that makes NetBSD great IMHO

I mean, it gets pretty close to that, and I don't even mind syslogd and powerd, but I'm confused why they enable stuff like postfix, inetd and makemandb without asking. Especially makemandb is pretty intensive on slow machines.

> "I was able to fix it by adding usermod disable wss to the bootloader line."

> Does he mean userconf

Whoopsie, that's on me, good catch!

XFile - https://fastestcode.org/xfile.html

That being said, I suspect 64MB could be enough for console-mode work, and if you recompiled the kernel without any unused drivers, perhaps you could make it under 32MB.

To be honest, I wouldn't notice this issue at all, if it wasn't for FreeBSD which refused to boot right off the bat. It has a more advanced bootloader though, so perhaps it does some extra sanity checks.

Comments URL: https://news.ycombinator.com/item?id=42431981

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Comments URL: https://news.ycombinator.com/item?id=41491675

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