Jeffrey Macko mackoj

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.
Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse

Swift Concurrency Manifesto

Author: Chris Lattner

Chinese Translation by Jason Yu

Exporting your 2FA tokens from Authy to transfer them into another 2FA application

IMPORTANT - Update regarding deprecation of Authy desktop apps

Past August 2024, Authy stopped supported the desktop version of their apps:
See Authy is shutting down its desktop app | The 2FA app Authy will only be available on Android and iOS starting in August for details.

And indeed, after a while, Authy changed something in their backend which now prevents the old desktop app from logging in. If you are already logged in, then you are in luck, and you can follow the instructions below to export your tokens.

If you are not logged in anymore, but can find a backup of the necessary files, then restore those files, and re-install Authy 2.2.3 following the instructions below, and it should work as expected.

Exporting (iCloud) Keychain and Safari credentials to a CSV file

WORK IN PROGRESS

The Mac OS Keychains is great if you spend your time in the Apple-verse. When you decide to mix it up or move away, you will want to take your password with you. Here's a process and the tools for exporting it's content to a CSV file in the format “example.com,user,pass”. This portable format would be pretty easy to import into Dashlane, LastPass, 1Password or whatever.

Here's my own list of the interesting stuff announced during this year's WWDC, collected from the keynotes, various Apple docs, blog posts and tweets.

If you're planning to watch the videos, I really recommend this Mac app that helps you download and watch them: https://github.com/insidegui/WWDC.

OS X El Capitan

http://www.apple.com/osx/elcapitan-preview/

split view - two apps side by side on full screen

	/*
	Thanks for @olebegemann
	code of keypath from this link
	https://oleb.net/blog/2017/01/dictionary-key-paths/
	*/

	struct KeyPath {
	var segments: [String]

	var isEmpty: Bool { return segments.isEmpty }


	get_latest_release() {
	curl --silent "https://api.github.com/repos/$1/releases/latest" \| # Get latest release from GitHub api
	grep '"tag_name":' \| # Get tag line
	sed -E 's/."([^"]+)"./\1/' # Pluck JSON value
	}

	# Usage
	# $ get_latest_release "creationix/nvm"
	# v0.31.4

	import Cocoa

	enum CoroutineState {
	case Fresh, Running, Blocked, Canceled, Done
	}

	struct CoroutineCancellation: ErrorType {}

	class CoroutineImpl<InputType, YieldType> {
	let body: (yield: YieldType throws -> InputType) throws -> Void

	/// Observes a run loop to detect any stalling or blocking that occurs.
	///
	/// This class is thread-safe.
	@interface GHRunLoopWatchdog : NSObject

	/// Initializes the receiver to watch the specified run loop, using a default
	/// stalling threshold.
	- (id)initWithRunLoop:(CFRunLoopRef)runLoop;

	/// Initializes the receiver to detect when the specified run loop blocks for

	//
	// EitherProtocol+Error.swift
	// CaoCaoKit
	//
	// Created by Seivan Heidari on 16/08/29.
	//
	//

	import Foundation