Alec Cunningham moosh3

Handy one-liners for sed

Mar. 23, 2001 - version 5.1 - compiled by Eric Pement [email protected]

Latest version of this file is usually at:

http://www.student.northpark.edu/pemente/sed/sed1line.txt
http://www.cornerstonemag.com/sed/sed1line.txt
This file is also available in Portuguese at:

tmux cheatsheet

As configured in my dotfiles.

start new:

tmux

start new with session name:

One-line Tree in Python

Using Python's built-in defaultdict we can easily define a tree data structure:

def tree(): return defaultdict(tree)

That's it!

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

This is a little trick I use to spin up the packages instalation on Debian/Ubuntu boxes in Vagrant.

I add a simple function that checks if a directory named something similar to ~/.vagrant.d/cache/apt/opscode-ubuntu-12.04/partial (it may have another path in Windows or MacOS) and create the directory if it doesn't already exist.

def local_cache(basebox_name)
  cache_dir = Vagrant::Environment.new.home_path.join('cache', 'apt', basebox_name)
  partial_dir = cache_dir.join('partial')
  partial_dir.mkdir unless partial_dir.exist?
 cache_dir

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

	#!/usr/bin/env python
	# -- coding: utf-8 --

	import urllib2

	gh_url = 'https://api.github.com'

	req = urllib2.Request(gh_url)

	password_manager = urllib2.HTTPPasswordMgrWithDefaultRealm()

	# This should be changed to your system's jenkins root JENKINS_ROOT="/var/lib/jenkins"
	JENKINS_USERS="$JENKINS_ROOT/users"
	JENKINS_JOBS="$JENKINS_ROOT/jobs"
	JENKINS_CONFIG="$JENKINS_ROOT/config.xml"

	# This variable is used so that we can verify that a user is not found
	FAIL_TEST=0

	exportUserFolder() {
	if [ -d "$JENKINS_USERS/$1" ]; then

	<html>
	<head>
	<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js" type="text/javascript"></script>
	<script src="http://www.skulpt.org/js/skulpt.min.js" type="text/javascript"></script>
	<script src="http://www.skulpt.org/js/skulpt-stdlib.js" type="text/javascript"></script>

	</head>

	<body>