weihanglo

本文譯自 [Tokio internals: Understanding Rust's asynchronous I/O framework from the bottom up][tokio-internals]。
Thanks [David Simmons][david-simmons] for this awesome article!

[Tokio][tokio] 是 Rust 的開發框架，用於開發非同步 I/O 程式（asynchronous I/O，一種事件驅動的作法，可實現比傳統同步 I/O 更好的延伸性、效能與資源利用）。可惜的是，Tokio 過於精密的抽象設計，招致難以學習的惡名。即使我讀完教程後，依然不認為自己充分內化這些抽象層，以便推斷實際發生的事情。

從前的非同步 I/O 相關開發經驗甚至阻礙我學習 Tokio。我習慣使用作業系統提供的 selection 工具（例如 Linux epoll）當作起點，再轉移至 dispatch、state machine 等等。倘若直接從 Tokio 抽象層出發，卻沒有清楚了解 epoll_wait() 在何處及如何發生，我會覺得難以連結每個概念。Tokio 與 future-driven 的方法就好像一個黑盒子。

mbinna

Effective Modern CMake

Getting Started

For a brief user-level introduction to CMake, watch C++ Weekly, Episode 78, Intro to CMake by Jason Turner. LLVM’s CMake Primer provides a good high-level introduction to the CMake syntax. Go read it now.

After that, watch Mathieu Ropert’s CppCon 2017 talk Using Modern CMake Patterns to Enforce a Good Modular Design (slides). It provides a thorough explanation of what modern CMake is and why it is so much better than “old school” CMake. The modular design ideas in this talk are based on the book [Large-Scale C++ Software Design](https://www.amazon.de/Large-Scale-Soft

roycyt

/etc/default/keyboard
XKBOPTIONS="ctrl:nocaps"

spaze

2023 update

ℹ️ Please note this research is from 2016 when Opera has first added their browser "VPN", even before the "Chinese deal" was closed. They have since introduced some real VPN apps but this below is not about them.

🕵️ Some folks also like to use this article to show a proof that the Opera browser is a spyware or that Opera sells all your data to 3rd parties or something like that. This article here doesn't say anything like that.

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When setting up (that's immediately when user enables it in settings) Opera VPN sends few API requests to https://api.surfeasy.com to obtain credentials and proxy IPs, see below, also see The Oprah Proxy.

The browser then talks to a proxy de0.opera-proxy.net (when VPN location is set to Germany), it's IP address can only be resolved from within Opera when VPN is on, it's 185.108.219.42 (or similar, see below). It's an HTTP/S proxy which requires auth.

drmalex07

README

Services declared as oneshot are expected to take some action and exit immediatelly (thus, they are not really services, no running processes remain). A common pattern for these type of service is to be defined by a setup and a teardown action.

Let's create a example foo service that when started creates a file, and when stopped it deletes it.

Define setup/teardown actions

Create executable file /opt/foo/setup-foo.sh:

TheBB

Emacs packages, features, files, layers, extensions, auto-loading, require, provide, use-package… All these terms getting you confused? Let’s clear up a few things.

Files

Emacs files contains code that can be evaluated. When evaluated, the functions, macros and modes defined in that file become available to the current Emacs session. Henceforth, this will be termed as loading a file.

One major problem is to ensure that all the correct files are loaded, and in the