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Generate a PDF from a Markdown file with Pandoc

Easy Steps For Mac OS

Have Homebrew installed and a markdown file you want to render to PDF.
Install Pandoc brew install pandoc
Install basictex brew cask install basictex - needed for the pdflatex tool.
Symlink the pdflatex to your /usr/local/bin so pandoc can easily find it. ln -s /Library/TeX/Root/bin/x86_64-darwin/pdflatex /usr/local/bin/pdflatex
Use Pandoc to generate a PDF from a Markdown file. pandoc input.md -o output.pdf

By default the margins are pretty large. To optionally change the margins: pandoc input.md -o output.pdf -V geometry:margin=1in

QEMU with VirtIO GPU Vulkan Support

With its latest reales qemu added the Venus patches so that virtio-gpu now support venus encapsulation for vulkan. This is one more piece to the puzzle towards full Vulkan support.

An outdated blog post on clollabora described in 2021 how to enable 3D acceleration of Vulkan applications in QEMU through the Venus experimental Vulkan driver for VirtIO-GPU with a local development environment. Following up on the outdated write up, this is how its done today.

Definitions

Let's start with the brief description of the projects mentioned in the post & extend them:

Upgrading PostgreSQL in Windows

The official documentation for PostgreSQL provides a guide to upgrading using pg_upgrade. However, it can be a bit like a treasure hunt with hidden traps. This gist will walk you through a clear and robust method for upgrading PostgreSQL on Windows, using the upgrade from version 14 to 16 as an example.

1. Install the New Version of PostgreSQL

Before you embark on the upgrade journey, make sure you have the new version installed. This is because the pg_upgrade utility used during the upgrade process belongs to the newer version.

To get started, visit the official download page, download the installer, and run it. A word of caution: do not overwrite the old installation, as you'll need its binaries and data for the upgrade.

Inital Ubuntu setup script

This script is meant to be run on a fresh Ubuntu LTS installation.

Using Gmail SMTP with Cloudflare Email Routing: Step-by-Step Guide

Learn how to send emails through Gmail SMTP with Cloudflare Email Routing in this comprehensive guide.

Step 1: Enable 2-Factor Authentication

To proceed with this method, ensure that you have enabled two-factor authentication for your Google account. If you haven't done so already, you can follow the link to set it up → Enable 2FA in your Google account.

Step 2: Create an App Password for Mail

I've never had great understanding of launchctl but the deprecation of the old commands with launchctl 2 (10.10) has been terrible as all resources only cover the old commands, and documentation for Apple utilities is generally disgracefully bad, with launchctl not dissembling.

Mad props to https://babodee.wordpress.com/2016/04/09/launchctl-2-0-syntax/ which contains most details

domains

Internally, launchd has several domains, but launchctl 1 would only ask for service names,

	//
	// main.swift
	// PokerTest
	//
	// Created by Reza Shirazian on 11/8/19.
	// Copyright © 2019 Reza Shirazian. All rights reserved.
	//

	import Foundation

	Latency Comparison Numbers (~2012)
	----------------------------------
	L1 cache reference 0.5 ns
	Branch mispredict 5 ns
	L2 cache reference 7 ns 14x L1 cache
	Mutex lock/unlock 25 ns
	Main memory reference 100 ns 20x L2 cache, 200x L1 cache
	Compress 1K bytes with Zippy 3,000 ns 3 us
	Send 1K bytes over 1 Gbps network 10,000 ns 10 us
	Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD

	// routes1.go
	func Routes1(mux *http.ServeMux) {
	mux.Handle("/route1/a", handler1A)
	mux.Handle("/route1/b", handler1B)
	mux.Handle("/route1/c", handler1C)
	}

	// routes2.go
	func Routes2(mux *http.ServeMux) {
	mux.Handle("/route2/x", handler2X)

	user nginx;
	worker_processes auto;
	error_log /var/log/nginx/error.log info;
	pid /var/run/nginx.pid;
	events { worker_connections 1024; }
	http {
	default_type text/html;
	log_format main '$remote_addr -> $request $status $body_bytes_sent bytes -> $upstream_addr';
	access_log /var/log/nginx/access.log main;