Repair of sabotaged mathematical glyphs in certain Linux distros.

Recently, I received a tip that some Linux users saw rubbish in place of certain Unicode glyphs appearing in the FFA series (in particular, in Ch. 14.) If the following two rows of symbols do not appear recognizably-identical in your WWW browser: ← → ⇠ ⇢ ⌊ ⌋ … the following fix is likely to […]

Defeating Vendor Lock-Ins: "Liebert GXT4."

Certain double-conversion UPS units by Liebert (in my case — a GXT4-2000RT120) appear to contain a boobytrap whereby off-the-shelf (needs two 12v/80mm) high-efficiency/quiet fans will not operate — the boot will abort with a Fan Out of Order error. The pill: install a 100 ohm wirewound resistor in parallel with the front fan connector (on […]

The 2021 Rack.

Thank you, 2020 Rack Service subscribers! I would like to wish all of you another great year of hygienic Linux on high-quality non-Fritzed iron! The 2021 service agreement is identical to the 2020 one. With the unfortunate exception that Deedbot Wallet is closing down on Dec. 25, 2020, and hence will no longer be accepted […]

"Finite Field Arithmetic." Chapter 21A-Ter: Fix for a False Alarm in Ch.14; "Litmus" Errata.

This article is part of a series of hands-on tutorials introducing FFA, or the Finite Field Arithmetic library. FFA differs from the typical "Open Sores" abomination, in that -- rather than trusting the author blindly with their lives -- prospective users are expected to read and fully understand every single line. In exactly the same […]

"Cryostat" Genesis.

Cryostat is a Fits-in-Head minimal (~700 LOC, including comments) static library for adding safe and reliable persistent storage to Ada data structures. It makes use of memory-mapped disk I/O via the MMap() system call, present in Linux (kernel 2.4 and newer) and all compatible operating systems. This mechanism permits efficient work with persistent data structures […]

"Finite Field Arithmetic." Chapter 21A-Bis: Fix for Lethal Flaw in Ch.15's Greatest Common Divisor.

This article is part of a series of hands-on tutorials introducing FFA, or the Finite Field Arithmetic library. FFA differs from the typical “Open Sores” abomination, in that — rather than trusting the author blindly with their lives — prospective users are expected to read and fully understand every single line. In exactly the same […]

"Finite Field Arithmetic." Chapter 21A: Extended GCD and Modular Multiplicative Inverse. (Part 1 of 3)

This article is part of a series of hands-on tutorials introducing FFA, or the Finite Field Arithmetic library. FFA differs from the typical “Open Sores” abomination, in that — rather than trusting the author blindly with their lives — prospective users are expected to read and fully understand every single line. In exactly the same […]

The Fossil Vault.

I have recently built two new WWW mirrors containing certain publicly-available software: 1. Historic Gentoo Distfiles. I have been using Gentoo for nearly all Linux-related work since 2007. It was “the lesser of evils”: to my knowledge, no other Linux variant ever offered a comparable level of rodenticidal control, while at the same time providing […]

"Watchglass" Genesis.

Update (Aug 2021) : billymg wrote a a very spiffy node explorer based on this program. Update (May 2020) : Support for “peers” command. ‘Watchglass’ is a simple program for monitoring the health of a constellation of Bitcoin nodes. The user interface is in the form of an IRC bot, based on my August 2019 […]

"Finite Field Arithmetic." Chapter 20D: "Litmus" Errata: Support for Nested Clearsigned Texts.

This article is part of a series of hands-on tutorials introducing FFA, or the Finite Field Arithmetic library. FFA differs from the typical “Open Sores” abomination, in that — rather than trusting the author blindly with their lives — prospective users are expected to read and fully understand every single line. In exactly the same […]