hackernews

1. Regex character “$” doesn’t mean “end-of-string” Total comment counts : 59 Summary This article discusses the behavior of the “$” character in Python’s regex module (re). While “^” signifies “start-of-string,” “$” is usually understood as “end-of-string.” However, it is revealed that the behavior of “$” is platform-dependent and not always symmetrical with “^.” In Python, with multiline mode disabled, “$” can match either the end of a string or a trailing newline before the end of a string....

1. Gaining kernel code execution on an MTE-enabled Pixel 8 Total comment counts : 8 Summary The article discusses a vulnerability, CVE-2023-6241, in the Arm Mali GPU that allows a malicious app to gain arbitrary kernel code execution and root access on an Android phone. The vulnerability affects devices with newer Arm Mali GPUs, such as Google’s Pixel 7 and Pixel 8 phones. The article explains that this vulnerability is a logic bug in the memory management unit of the GPU and is capable of bypassing the Memory Tagging Extension (MTE), a powerful mitigation against memory corruption....

1. Experience with an Uncommon Lisp (1986) [pdf] Total comment counts : 5 Summary error Top 1 Comment Summary The article discusses YKTLISP and its predecessor, providing a link to further information on the IBM LISP family. Top 2 Comment Summary The article discusses the development process of the new IBM Research Lisp system and highlights the importance of a paper by Bobrow and Wegbreit proposing a new control structure called the spaghetti stack....

1. The return of the frame pointers Total comment counts : 37 Summary The article discusses the issue of broken debuggers and profilers and specifically focuses on flame graphs. It explains that when flame graphs appear fine at first glance, there can still be samples in the wrong place and missing frames. The problem arises when the default libc (C library) used in a system is compiled without frame pointers, causing a partial stack that lacks application frames....

1. On clock faces, 4 is Expressed as IIII, not IV Total comment counts : 40 Summary This article discusses the use of Roman numerals on clocks and the unconventional notation of “4” as “IIII” instead of “IV”. It explains that this convention dates back to the late 14th century when King Charles V of France believed that “IV” brought bad luck because it subtracted 1 from his title, 5. The notation “IIII” was used in the Wells Cathedral clock in England and became conventional in the industry due to its visual balance on radial dial plates....

1. The Oregon Outback International Dark Sky Sanctuary Total comment counts : 29 Summary A 2.5 million-acre region in southern Oregon, including Hart Mountain, Lake Abert, and Summer Lake, has been designated as the largest Dark Sky Sanctuary in the world. It was named the Oregon Outback International Dark Sky Sanctuary by DarkSky International, an organization dedicated to preserving dark skies. The project is a collaboration between various officials, individuals, business owners, and tourism agencies....

1. Spreadsheets are all you need Total comment counts : 40 Summary The article discusses a low-code introduction to Large Language Models (LLMs) called “Spreadsheets-are-all-you-need.” It explains that the implementation of the forward pass of GPT2 (a predecessor to ChatGPT) is done entirely in Excel using standard spreadsheet functions. The article mentions that this same Transformer architecture is used in various LLMs such as OpenAI’s ChatGPT and Google’s Bard/Gemini. It provides a 10-minute demo video that walks through the high-level architecture of GPT2 and how it is implemented in an Excel spreadsheet....

1. JIT WireGuard Total comment counts : 20 Summary The article is about Fly.io, a company that uses WireGuard to make their system faster and more scalable. They have implemented WireGuard in unique ways, such as conjuring a TCP/IP stack for every instance of their CLI. However, they encountered two problems: unreliable message delivery with NATS and leftover WireGuard peers after running flyctl. To solve these issues, they decided to have gateways pull configurations from their API on demand instead of pushing them....

1. Cloning a Laptop over NVMe TCP Total comment counts : 36 Summary The author of the article purchased a new laptop and wanted to avoid the hassle of setting it up from scratch. Their colleague suggested copying the entire disk from the old laptop to the new one. The author explains the steps they took to accomplish this, which involved exposing the disk using NVME over TCP, connecting it over the network, and performing a full disk copy using the dd command....

1. (How to Write a (Lisp) Interpreter (In Python)) (2010) Total comment counts : 18 Summary This article discusses the importance and basic concepts of compilers and interpreters. It focuses on the syntax and semantics of Scheme programs and compares Scheme syntax to other programming languages. The article also introduces a simplified version of Scheme called the Lispy Calculator, which only uses five syntactic forms. It explains the allowable expressions in Lispy Calculator and describes what a language interpreter does, including the parsing component and the internal representation of the program....