maiha

TL;DR

• Leaky bucket : キューイングして出力量(consume)で調節 (アルゴリズムというかキューを使って調節)
• Token bucket : 定期的に資源を追加し平均値を調節。バーストに強い (ソシャゲのスタミナ回復)
• Fixed window counters : 単位時間あたりの上限値を指定。キューを使わないLeaky bucket。境界の2倍問題あり
• Sliding window log : 総数(counters)でなくアクセス時刻(log)で管理。境界問題を解消する一方、消費増加がぱない(Int → Array(Time))
• Sliding window counters : countersのままで、単位時間の割合計算によって境界問題を解消。これにしておけば間違いない

参考: 様々なrate limitアルゴリズム

• https://christina04.hatenablog.com/entry/rate-limiting-algorithm
• 日本語。メリットとデメリットも解説されており、デメリットを克服する形で次のアルゴリズムの説明に入るので、全体がわかりやすい

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

josephg

#include <sys/socket.h>
#include <sys/un.h>
#include <sys/event.h>
#include <netdb.h>
#include <assert.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdio.h>
#include <errno.h>

wxdao

#include <netinet/in.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/kern_control.h>
#include <net/if_utun.h>
#include <sys/ioctl.h>
#include <sys/kern_event.h>

int open_utun(int num) {
	int err;

joepie91

Not all random values are created equal - for security-related code, you need a specific kind of random value.

A summary of this article, if you don't want to read the entire thing:

• Don't use Math.random(). There are extremely few cases where Math.random() is the right answer. Don't use it, unless you've read this entire article, and determined that it's necessary for your case.
• Don't use crypto.getRandomBytes directly. While it's a CSPRNG, it's easy to bias the result when 'transforming' it, such that the output becomes more predictable.
• If you want to generate random tokens or API keys: Use uuid, specifically the uuid.v4() method. Avoid node-uuid - it's not the same package, and doesn't produce reliably secure random values.
• If you want to generate random numbers in a range: Use random-number-csprng.

You should seriously consider reading the entire article, though - it's

dreikanter

Symmetic encryption

For symmetic encryption, you can use the following:

To encrypt:

openssl aes-256-cbc -salt -a -e -in plaintext.txt -out encrypted.txt

To decrypt:

mono0926

gitにおけるコミットログ/メッセージ例文集100の転載

例文を組み込んだAlfred Workflowを作りました: Alfred Git Commit Message Example

以下転載:

---

RafaelMCarvalho

class Edition < ActiveRecord::Base
  scope :distances_any, -> (*distances) {
    where("distances ?| array[:values]", values: distances)
  }

  private

  def self.ransackable_scopes(auth_object = nil)
    %i(distances_any)
  end

kotakanbe

モヒカンslackのチャネルリスト(毎日 AM 5:00 自動更新)

詳細はQiita:究極のIT系最新技術情報収集用Slackチーム公開 - モヒカンSlack -を参照。

参加は

• Slackin
• Google Forms

gubatron

DHT Walkthrough Notes

I've put together these notes as I read about DHT's in depth and then learned how the libtorrent implementation based on the Kademlia paper actually works.

What problem does this solve?

400,000,000,000 (400 billion stars), that's a 4 followed by 11 zeros. The number of atoms in the universe is estimated to be around 10^82. A DHT with keys of 160 bits, can have 2^160 possible numbers, which is around 10^48