Dragoș Haiduc drakiula

1. Clone your fork:

git clone [email protected]:YOUR-USERNAME/YOUR-FORKED-REPO.git

2. Add remote from original repository in your forked repository:

cd into/cloned/fork-repo
git remote add upstream git://github.com/ORIGINAL-DEV-USERNAME/REPO-YOU-FORKED-FROM.git
git fetch upstream

git discard all local changes/commits and pull from upstream

git reset --hard origin/master

git pull origin master

File Magic Numbers

Magic numbers are the first bits of a file which uniquely identify the type of file. This makes programming easier because complicated file structures need not be searched in order to identify the file type.

For example, a jpeg file starts with ffd8 ffe0 0010 4a46 4946 0001 0101 0047 ......JFIF.....G ffd8 shows that it's a JPEG file, and ffe0 identify a JFIF type structure. There is an ascii encoding of "JFIF" which comes after a length code, but that is not necessary in order to identify the file. The first 4 bytes do that uniquely.

This gives an ongoing list of file-type magic numbers.

Image Files

How Do I Into Git?

a helpful primer for users sick of git's poorly-named commands

I've used Git since 2011, and this is the stuff that I've always had to Google to remember. I hope it helps you not hate Git so much.

	# Author: Pieter Noordhuis
	# Description: Simple demo to showcase Redis PubSub with EventMachine
	#
	# Update 7 Oct 2010:
	# - This example does not appear to work with Chrome >=6.0. Apparently,
	# the WebSocket protocol implementation in the cramp gem does not work
	# well with Chrome's (newer) WebSocket implementation.
	#
	# Requirements:
	# - rubygems: eventmachine, thin, cramp, sinatra, yajl-ruby

	#!/bin/sh

	# This program has two feature.
	#
	# 1. Create a disk image on RAM.
	# 2. Mount that disk image.
	#
	# Usage:
	# $0 <dir> <size>
	#

	-- show running queries (pre 9.2)
	SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
	FROM pg_stat_activity
	WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
	ORDER BY query_start desc;

	-- show running queries (9.2)
	SELECT pid, age(clock_timestamp(), query_start), usename, query
	FROM pg_stat_activity
	WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'

	git rebase --interactive HEAD~2

	# we are going to squash c into b
	pick b76d157 b
	pick a931ac7 c

	# squash c into b
	pick b76d157 b
	s a931ac7 c

	sudo wget http://repos.fedorapeople.org/repos/dchen/apache-maven/epel-apache-maven.repo -O /etc/yum.repos.d/epel-apache-maven.repo
	sudo sed -i s/\$releasever/6/g /etc/yum.repos.d/epel-apache-maven.repo
	sudo yum install -y apache-maven
	mvn --version