Jinzhou Zhang lotabout

Howto: Install Alpine Linux 3.3 on VirtualBox OSX

Latest Standard ISO version x86_64 is recommended (http://alpinelinux.org/downloads/)
Create new VM ("Linux 2.6 / 3.x / 4.x (64-bit)")
1 CPU w/ 512BM RAM and 1 GB default (VDI) disk is more than sufficient
Default networking (NAT)
Boot and add Alpine ISO as attached virtual install media
Default root password is blank (though note - ssh PermitRootLogin defaults to disallow blank passwords and: prohibit-password; switch to yes for Host ssh)
Run setup-alpine
Defaults are fine, but you do want "sys" disk setup to sda, y to confirm

Libvirt

yum group install -y "Development Tools"
yum -y install qemu-kvm libvirt virt-install bridge-utils libvirt-devel  libxslt-devel libxml2-devel libvirt-devel libguestfs-tools-c

echo "net.ipv4.ip_forward = 1"|sudo tee /etc/sysctl.d/99-ipforward.conf
sysctl -p /etc/sysctl.d/99-ipforward.conf

Python 2.7. Unicode Errors Simply Explained

I know I'm late with this article for about 5 years or so, but people are still using Python 2.x, so this subject is relevant I think.

Some facts first:

Unicode is an international encoding standard for use with different languages and scripts
In python-2.x, there are two types that deal with text.
1. str is an 8-bit string.

unicode is for strings of unicode code points.

What forces layout / reflow

All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.

Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.

Element APIs

Getting box metrics

elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent

Get the current Unix timestamp (seconds from 1970-01-01T00:00:00Z) in SQL.

MySQL: UNIX_TIMESTAMP()
PostgreSQL: CAST(EXTRACT(epoch FROM NOW()) AS INT)
MS SQL: DATEDIFF(s, '1970-01-01', GETUTCDATE())
Oracle: (CAST(SYS_EXTRACT_UTC(SYSTIMESTAMP) AS DATE) - DATE'1970-01-01') * 86400

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

	#!/bin/bash
	# Install Spark on CentOS 7
	yum install java -y
	java -version

	yum install wget -y
	wget http://downloads.typesafe.com/scala/2.11.7/scala-2.11.7.tgz
	tar xvf scala-2.11.7.tgz
	sudo mv scala-2.11.7 /usr/lib
	sudo ln -s /usr/lib/scala-2.11.7 /usr/lib/scala

	--- Actions ---
	$Copy <M-C>
	$Cut <M-X> <S-Del>
	$Delete <Del> <BS> <M-BS>
	$LRU
	$Paste <M-V>
	$Redo <M-S-Z> <A-S-BS>
	$SearchWeb <A-S-G>
	$SelectAll <M-A>
	$Undo <M-Z>

	dir="." #Set the default temp dir
	tmpA1="$dir/spectrumhist_1_$$.png"
	tmpB1="$dir/spectrumhist_1_$$.cache"
	trap "rm -f $tmpA1 $tmpB1; exit 0" 0 #remove temp files
	trap "rm -f $tmpA1 $tmpB1; exit 1" 1 2 3 15 #remove temp files
	if [ $# -eq 2 ]
	then
	colors=$2
	else
	colors=8

	// ==UserScript==
	// @name 百度网盘aria2导出工具
	// @author acgotaku311
	// @description 一个方便吧百度网盘的Aria2rpc导出的脚本。
	// @encoding utf-8
	// @include http://n.baidu.com/s/
	// @include http://n.baidu.com/disk/home
	// @include http://n.baidu.com/share/link
	// @include https://n.baidu.com/s/
	// @include https://n.baidu.com/disk/home