Dev1 Galaxy Forum / Today I Learned

Re: Today I Learned

dummy@example.com (dice) — Sun, 04 Jul 2021 12:26:44 +0000

Yesterday really but playing around with it some more today. I seem to be gravitating towards encryption, fascinating stuff imo, especially this post quantum computing cryptography.

https://gitea.blesmrt.net/exa/codecrypt

its in the repos - do a # apt install codecrypt

Codecrypt - ccr
The post-quantum cryptography tool.
Codecrypt is currently unmaintained, although I still successfully use it. If you are interested in developing/maintaining it, ping me.
About
This is a GnuPG-like unix program for encryption and signing that uses only quantum-computer-resistant algorithms:
McEliece cryptosystem (compact QC-MDPC variant) for encryption
Hash-based Merkle tree algorithm (FMTSeq variant) for digital signatures
Codecrypt is free software. The code is licensed under terms of LGPL3 in a good hope that it will make combinations with other tools easier.
Why this?
Go read http://pqcrypto.org/

Re: Today I Learned

dummy@example.com (Head_on_a_Stick) — Thu, 01 Jul 2021 06:47:25 +0000

Disk images can be mounted directly if the partition offset is known:

$ gdisk -l disk.img
[...]
Number  Start (sector)    End (sector)  Size       Code  Name
   1              34            2047   1007.0 KiB  EF02  BIOS boot partition
   2            2048        20971486   10.0 GiB    8300  Linux filesystem
$ sudo mount -o offset=$((2048*512)) disk.img /mnt
$ ls /mnt
bin   dev  home  lost+found  mnt  proc  run   srv  tmp  var
boot  etc  lib   media       opt  root  sbin  sys  usr
$

Re: Today I Learned

dummy@example.com (ralph.ronnquist) — Thu, 01 Jul 2021 05:05:25 +0000

Note that recently the kernel's loop module has max_part=0 by default, which means that the partitions (eg /dev/loop0p1) will not be set up. Many strands of hair have been lost due to this.

To get the good behaviour, I've added a file /etc/modprobe.d/loop.conf with the following line:

options loop max_part=15

before the loading of the loop module. Almost any number other than 15, within bounds, is also fine.

Re: Today I Learned

dummy@example.com (Tatwi) — Thu, 01 Jul 2021 01:42:22 +0000

TIL how to mount the disk image file I use as a hard drive in DOS with PCem. This is one of those things that I used to know at one point, but suffered from the o'l "use it or lose it" problem.

Beforehand: Run PCem, configure the machine, make a new hard drive image, run the machine, configure the drive in the BIOS, install DOS on it (using floppy disk images), exit PCem.

These commands must be run with root privilages (I use sudo).

# Attach the hard drive image file as a loopback device
losetup -f -P /home/rob/.pcem/disks/dos_622_62mb.img

# Verify the loopback device is the expected number and has the expected partition
losetup -l

# Mount the partition and open in the file explorer
mount /dev/loop0p1 /mnt
caja /mnt

Copy files to/from the DOS hard drive.

# Disconnect and unmount the hard drive image file
umount /dev/loop0p1
losetup -d /dev/loop0

# Verify loopback is cleared (shouldn't output anything)
losetup -l

It's still way less of a hassle to use DOSBox, as it uses files directly on your normal file system, but each emulator has its use cases.

Re: Today I Learned

dummy@example.com (dice) — Wed, 30 Jun 2021 14:43:58 +0000

starbreaker wrote:

TIL that cpupower-gui is a handy way to throttle clock speeds on my machines so that they aren't running quite as hot in the summer (they make good space heaters in the winter).

Nice gui utility that one. So many hidden gems inside debian.

Today i learnt about cryfs.

https://www.cryfs.org/tutorial

cryfs - cryptographic filesystem for the cloud

CryFS encrypts your files, so you can safely store them anywhere.

       The  goal  of  CryFS is not only to keep file contents, but also file sizes, metadata and directory structure confidential.  CryFS uses en‐
       crypted same-size blocks to store both the files themselves and the block's relations to another.  These blocks are  stored  as  individual
       files in the base directory, which can then be synchronized with cloud services such as Dropbox.

       The  blocks  are  encrypted using a random key, which is stored in a configuration file encrypted by the user's passphrase.  By default, it
       will be stored together with the data in the base directory, but you can choose a different location if you do not want it in your cloud or
       when using a weak passphrase.

Re: Today I Learned

dummy@example.com (starbreaker) — Tue, 29 Jun 2021 14:15:26 +0000

TIL that cpupower-gui is a handy way to throttle clock speeds on my machines so that they aren't running quite as hot in the summer (they make good space heaters in the winter).

Re: Today I Learned

dummy@example.com (GlennW) — Wed, 23 Jun 2021 06:59:29 +0000

Today I Learned: that if I follow the simple instructions on the webpages that come with the distro (Beowulf 3.1.1)
I can tether my iphone to usb and have the internet working rather that wait for wicd to start asking questions
and then waiting some more. (on my laptop (Toshiba r552j))

Thank you for the well documented web pages that are included with the (unpacked) .iso

Re: Today I Learned

dummy@example.com (zapper) — Tue, 22 Jun 2021 12:15:00 +0000

sgage wrote:

zapper wrote:
dice wrote:
Good question, i was thinking the same. Perhaps the 64 has some mods? I highly doubt a computer from 1982 would be able to run devuan beowulf, but i would be happy to be proven wrong.
Wait 64mb of ram? you say? That seems a bit unlikely, I mean I could understand 32mb... and maybe jwm if its 32 bit and be using something like console-tdm to start it, if you turn off certain services... *cough* dbus *cough*
Even then, 32mb seems like a stretch, but yeah, 64K sounds insanely low to be able to run devuan...
You'd have a better chance of using OpenBSD for something that small...
Just sayin...
I would also love to be proven wrong...
Not just the 64K of RAM, either. When was the kernel ported to 8-bit 6502 (or 6509 - whatever variant they used)? Never.

Ah, lots of problems then! Well, I wonder though, if any BSD's support 8 bit still...

OpenBSD supposedly could, but it probably has very slow support I imagine...

If it does at all.

Looks like it doesn't at the moment...
https://www.openbsd.org/plat.html

Although it does support this:

luna88k

Dunno about NetBSD though. That might lol.

Yep it does:

https://wiki.netbsd.org/ports/amiga/

Re: Today I Learned

dummy@example.com (sgage) — Tue, 22 Jun 2021 11:17:45 +0000

andyprough wrote:

sgage wrote:
Not just the 64K of RAM, either. When was the kernel ported to 8-bit 6502 (or 6509 - whatever variant they used)? Never.
No, it wasn't ported, and I'm not really running Beowulf on one, but a unix-like kernel was written in 6502 assembly by the LUnix (Little Unix) project folks between 1993 and 2004. The LUnix home page is still up for anyone wanting to download LUnix and take it for a spin on their favorite Commodore 64 rig: http://lng.sourceforge.net/

Wow, that's pretty cool! I was pretty good at 6502 assembly language back in the late 70's/early 80's - strange days! My first computer was a Commodore PET/CBM. It's amazing what you can do in assembly!

Re: Today I Learned

dummy@example.com (andyprough) — Tue, 22 Jun 2021 05:23:33 +0000

sgage wrote:

Not just the 64K of RAM, either. When was the kernel ported to 8-bit 6502 (or 6509 - whatever variant they used)? Never.

No, it wasn't ported, and I'm not really running Beowulf on one, but a unix-like kernel was written in 6502 assembly by the LUnix (Little Unix) project folks between 1993 and 2004. The LUnix home page is still up for anyone wanting to download LUnix and take it for a spin on their favorite Commodore 64 rig: http://lng.sourceforge.net/

Re: Today I Learned

dummy@example.com (sgage) — Mon, 21 Jun 2021 20:12:37 +0000

zapper wrote:

dice wrote:
fsmithred wrote:
@andyprough:
How do you run linux on a computer with only 64k RAM???
Good question, i was thinking the same. Perhaps the 64 has some mods? I highly doubt a computer from 1982 would be able to run devuan beowulf, but i would be happy to be proven wrong.
Wait 64mb of ram? you say? That seems a bit unlikely, I mean I could understand 32mb... and maybe jwm if its 32 bit and be using something like console-tdm to start it, if you turn off certain services... *cough* dbus *cough*
Even then, 32mb seems like a stretch, but yeah, 64K sounds insanely low to be able to run devuan...
You'd have a better chance of using OpenBSD for something that small...
Just sayin...
I would also love to be proven wrong...

Not just the 64K of RAM, either. When was the kernel ported to 8-bit 6502 (or 6509 - whatever variant they used)? Never.

Re: Today I Learned

dummy@example.com (zapper) — Mon, 21 Jun 2021 17:16:12 +0000

dice wrote:

fsmithred wrote:
@andyprough:
How do you run linux on a computer with only 64k RAM???
Good question, i was thinking the same. Perhaps the 64 has some mods? I highly doubt a computer from 1982 would be able to run devuan beowulf, but i would be happy to be proven wrong.

Wait 64mb of ram? you say? That seems a bit unlikely, I mean I could understand 32mb... and maybe jwm if its 32 bit and be using something like console-tdm to start it, if you turn off certain services... *cough* dbus *cough*

Even then, 32mb seems like a stretch, but yeah, 64K sounds insanely low to be able to run devuan...

You'd have a better chance of using OpenBSD for something that small...

Just sayin...

I would also love to be proven wrong...

Re: Today I Learned

dummy@example.com (dice) — Mon, 21 Jun 2021 15:48:23 +0000

golinux wrote:

dice wrote:
Today i learned about this very cool link.
https://oldcomputers.net/
Steve's Old Computer Museum!
Early personal computers were nothing like present day computers - they had personality!
Each was different and more exciting than the previous, with new features and capabilities.
old computer This website is dedicated to the preservation and display of these vintage computer systems.
To the left you can "click" and explore old computers from the dawn of time!
For fun, view 150 old computers all at the same time to appreciate how diverse and interesting they are
Well, here is some Devuan trivia that's not so trivial. The Devuan Board of Trustees has 3 members who are involved with computer preservation!
Gabriele “Asbesto” Zaverio (MusIF) :: director, “Museo dell’Informatica Funzionante” computer museum
Emiliano Russo (MIAI) :: director, “Museo Interattivo di Archeologia Informatica” computer museum
Stefania Calcagno (ESOCOP) :: president, European Society for Computer Preservation
You can find that info on our website at https://www.devuan.org/os/team

Thanks for sharing, i particularly liike the ESoCop link, good works.

Re: Today I Learned

dummy@example.com (dice) — Mon, 21 Jun 2021 15:46:05 +0000

fsmithred wrote:

@andyprough:
How do you run linux on a computer with only 64k RAM???

Good question, i was thinking the same. Perhaps the 64 has some mods? I highly doubt a computer from 1982 would be able to run devuan beowulf, but i would be happy to be proven wrong.

Re: Today I Learned

dummy@example.com (golinux) — Mon, 21 Jun 2021 15:34:10 +0000

dice wrote:

Today i learned about this very cool link.
https://oldcomputers.net/
Steve's Old Computer Museum!
Early personal computers were nothing like present day computers - they had personality!
Each was different and more exciting than the previous, with new features and capabilities.
old computer This website is dedicated to the preservation and display of these vintage computer systems.
To the left you can "click" and explore old computers from the dawn of time!
For fun, view 150 old computers all at the same time to appreciate how diverse and interesting they are

Well, here is some Devuan trivia that's not so trivial. The Devuan Board of Trustees has 3 members who are involved with computer preservation!

Gabriele “Asbesto” Zaverio (MusIF) :: director, “Museo dell’Informatica Funzionante” computer museum

Emiliano Russo (MIAI) :: director, “Museo Interattivo di Archeologia Informatica” computer museum

Stefania Calcagno (ESOCOP) :: president, European Society for Computer Preservation

You can find that info on our website at https://www.devuan.org/os/team