J Christoph Winter cheesemid

1.14.x Chunk Loading

Chunk loading operates differently in 1.14 than in previous Minecraft versions. This document is intended to be an overview of the 1.14 system.

In 1.14, chunk loading starts with tickets. A ticket is:

a ticket type
a load level
optionally, a time-to-live

Preparing Ubuntu 18.04LTS as an OpenCL development platform:

With OpenCL, the installable client drivers (ICDs) are normally issued with the accelerator's device drivers, namely:

The NVIDIA CUDA toolkit (and the device driver) for NVIDIA GPUs.
AMD's RoCM for GCN-class AMD hardware.
Intel's beignet and the newer Neo compute runtime.

The purpose of the installable client driver model is to allow multiple OpenCL platforms to coexist on the same platform. That way, multiple OpenCL accelerators, be they discrete GPUs paired with a combination of FPGAs and integrated GPUs can all coexist.

Falsehoods programmers believe about time

This is a compiled list of falsehoods programmers tend to believe about working with time.

Don't re-invent a date time library yourself. If you think you understand everything about time, you're probably doing it wrong.

Falsehoods

There are always 24 hours in a day.
February is always 28 days long.
Any 24-hour period will always begin and end in the same day (or week, or month).

Recovering deleted files in Ubuntu with ext4 filesystem

Recently, I deleted some files by mistake in a Ubuntu machine with an ext4 fs. These notes document the steps I took to get them back.

Important

this procedure assumes that the partition that contained the deleted files is different from the root partition, as that was the scenario with which I had to deal (deleted files were in my home dir). The procedure needs that the partition that contained the files is unmounted, so if the deleted files were in the root partition, the process would be a bit different (e.g. storing the fs journal in a USB stick, using a live CD/USB to boot and issue the commands, etc.)
if something is not clear, you need more information, etc. check the sources below

With that out the way, let's begin.

How to fix Chromebook "no sound" after installing Ubuntu

Open up a terminal window and type sudo alsa force-unload to kill the audio services
Replace the system’s sound config file with the downloaded version:
- Type sudo cp ~/Downloads/asound.state /var/lib/alsa
Reboot your Chromebook

Raspberry Pi Zero OTG Mode

Simple guide for setting up OTG modes on the Raspberry Pi Zero - By Andrew Mulholland (gbaman).

The Raspberry Pi Zero (and model A and A+) support USB On The Go, given the processor is connected directly to the USB port, unlike on the B, B+ or Pi 2 B, which goes via a USB hub.
Because of this, if setup to, the Pi can act as a USB slave instead, providing virtual serial (a terminal), virtual ethernet, virtual mass storage device (pendrive) or even other virtual devices like HID, MIDI, or act as a virtual webcam!
It is important to note that, although the model A and A+ can support being a USB slave, they are missing the ID pin (is tied to ground internally) so are unable to dynamically switch between USB master/slave mode. As such, they default to USB master mode. There is no easy way to change this right now.
It is also important to note, that a USB to UART serial adapter is not needed for any of these guides, as may be documented elsewhere across the int

	@import 'https://fonts.googleapis.com/css?family=Open+Sans';

	* {
	-webkit-box-sizing: border-box;
	box-sizing: border-box;
	}

	body {
	font-family: 'Open Sans', sans-serif;
	line-height: 1.75em;

	.data
	hello:
	.string "Hello world!\n"

	.text
	.globl _start
	_start:
	movl $4, %eax # write(1, hello, strlen(hello))
	movl $1, %ebx
	movl $hello, %ecx