iamjarvo

if _, err := os.Stat("/path/to/whatever"); os.IsNotExist(err) {
	// path/to/whatever does not exist
}

if _, err := os.Stat("/path/to/whatever"); !os.IsNotExist(err) {
	// path/to/whatever exists
}

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/*
    Example for AWS SQL Server RDS instance:
    - create database
    - create login with basic permissions

    Since RDS is managed there are some restrictions when creating users and assigning
    permissions. This procedure shows how to create a database and login with combinations
    of ddl, read and write permissions.
*/
create procedure #createdbuser (

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##TCP FLAGS##

Unskilled Attackers Pester Real Security Folks
==============================================
                     TCPDUMP FLAGS
Unskilled =  URG  =  (Not Displayed in Flag Field, Displayed elsewhere) 
Attackers =  ACK  =  (Not Displayed in Flag Field, Displayed elsewhere)
Pester    =  PSH  =  [P] (Push Data)
Real      =  RST  =  [R] (Reset Connection)
Security  =  SYN  =  [S] (Start Connection)

iamjarvo

App configuration in environment variables: for and against

For (some of these as per the 12 factor principles) 

1) they are are easy to change between deploys without changing any code

2) unlike config files, there is little chance of them being checked
into the code repo accidentally

3) unlike custom config files, or other config mechanisms such as Java

iamjarvo

Tabs and Windows

Function	Shortcut
New Tab	⌘ + T
Close Tab or Window	⌘ + W (same as many mac apps)
Go to Tab	⌘ + Number Key (ie: ⌘2 is 2nd tab)
Go to Split Pane by Direction	⌘ + Option + Arrow Key
Cycle iTerm Windows	⌘ + backtick (true of all mac apps and works with desktops/mission control)

iamjarvo

ssh-keygen -t rsa -b 4096 -N '' -C "rthijssen@gmail.com" -f ~/.ssh/id_rsa
ssh-keygen -t rsa -b 4096 -N '' -C "rthijssen@gmail.com" -f ~/.ssh/github_rsa
ssh-keygen -t rsa -b 4096 -N '' -C "rthijssen@gmail.com" -f ~/.ssh/mozilla_rsa

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;; When executed, this file will run a basic web server
;; on http://localhost:8080 that will display the text
;; 'Hello World'.

(ns ring.example.hello-world-2
  (:use ring.util.response
        ring.adapter.jetty))

(defn handler [request]
  (-> (response "Hello World")

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;; When executed, this file will run a basic web server
;; on http://localhost:8080 that will display the text
;; 'Hello World'.

(ns ring.example.hello-world-2
  (:use ring.util.response
        ring.adapter.jetty))

(defn handler [request]
  (-> (response "Hello World")

iamjarvo

Prologue

I wrote this answer on stackexchange, here: https://stackoverflow.com/posts/12597919/

It was wrongly deleted for containing "proprietary information" years later. I think that's bullshit so I am posting it here. Come at me.

The Question

Amazon is a SOA system with 100s of services (or so says Amazon Chief Technology Officer Werner Vogels). How do they handle build and release?

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Problem

When starting Emacs.app on Mac, the Emacs doesn't have some environment variable set correctly. Typically it is terrible when you use GPG, pinentry-mac, gpg-agent But also a lot of different variables used to make git works correctly, etc...

Solution

1. Create the file ~/bin/init-app-env.sh: