defunkt

# Video: http://rubyhoedown2008.confreaks.com/08-chris-wanstrath-keynote.html

Hi everyone, I'm Chris Wanstrath.

When Jeremy asked me to come talk, I said yes.  Hell yes.  Immediately.  But
then I took a few moments and thought, Wait, why?  Why me?  What am I supposed
to say that's interesting?  Something about Ruby, perhaps.  Maybe the
future of it.  The future of something, at least.  That sounds
keynote-y.

henrik

Install ImageMagick for image conversion:

brew install imagemagick

Install tesseract for OCR:

brew install tesseract --all-languages

Or install without --all-languages and install them manually as needed.

jboner

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

jasonrudolph

5 entertaining things you can find with the GitHub Search API

Let's have some command-line fun with curl, [jq][1], and the [new GitHub Search API][2].

Today we're looking for:

• The hottest repositories created in the last week.
• The oldest user accounts with zero followers. (So sad.)
• Issue trends by language.
• Clojure projects defying convention.

rahbirul

#!/bin/bash

#Naive calculation of QPS from Apache Log
#Usage: qps.sh /path/to/logfile

LOG=$1

START=$(head -n 1 $LOG | cut -d ' ' -f 4 | tr -d [)
END=$(tail -n 1 $LOG | cut -d ' ' -f 4 | tr -d [)

jasonrobertfox

#!/bin/sh

exec < /dev/tty
./.git/hooks/validate_commit.rb $1

Kartones

PSQL

Magic words:

psql -U postgres

Some interesting flags (to see all, use -h or --help depending on your psql version):

• -E: will describe the underlaying queries of the \ commands (cool for learning!)
• -l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)

josephspurrier

/*
********************************************************************************
Golang - Asterisk and Ampersand Cheatsheet
********************************************************************************

Also available at: https://play.golang.org/p/lNpnS9j1ma

Allowed:
--------
p := Person{"Steve", 28} 	stores the value

jashkenas

var active = false;

function changeRefer(details) {
  if (!active) return;
  
  for (var i = 0; i < details.requestHeaders.length; ++i) {
    if (details.requestHeaders[i].name === 'Referer') {
      details.requestHeaders[i].value = 'http://www.google.com/';
      break;
    }

hfreire

# Install QEMU OSX port with ARM support
sudo port install qemu +target_arm
export QEMU=$(which qemu-system-arm)

# Dowload kernel and export location
curl -OL \
https://github.com/dhruvvyas90/qemu-rpi-kernel/blob/master/kernel-qemu-4.1.7-jessie
export RPI_KERNEL=./kernel-qemu-4.1.7-jessie

# Download filesystem and export location