Jonas Bülow jbulow

How to get a stack trace for each thread in a running python script

Sometimes a python script will simply hang forever with no indication of where things went wrong. Perhaps it's polling a service that will never return a value that allows the program to move forward. Here's a way to see where the program is currently stuck.

Install gdb and pyrasite

Install gdb.

# Redhat, CentOS, etc

Hello software developers,

Please check your code to ensure you're not making one of the following mistakes related to cryptography.

I. General Mistakes

Writing your own home-grown cryptography primitives (For example: Mifare Classic)
- Exception: For the sake of learning, but don't deploy it in production.
Using a fast hash function (e.g. MD5, SHA256) for storing passwords. Use bcrypt instead.
Not using a cryptographically secure random number generator

TL;DR

Create 5GB FreeBSD image.
Install FreeBSD on xhyve.
Mount host directory.

Requisites

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.


	(* Good morning everyone, I'm currently learning ocaml for one of my CS class and needed to implement
	an avl tree using ocaml. I thought that it would be interesting to go a step further and try
	to verify the balance property of the avl tree using the type system. Here's the resulting code
	annotated for people new to the ideas of type level programming :)
	*)

	(* the property we are going to try to verify is that at each node of our tree, the height difference between
	the left and the right sub-trees is at most of 1. *)

	/****************************************************************************/
	/* AM335x_PRU.cmd */
	/* Copyright (c) 2015 Texas Instruments Incorporated */
	/* */
	/* Description: This file is a linker command file that can be used for */
	/* linking PRU programs built with the C compiler and */
	/* the resulting .out file on an AM335x device. */
	/****************************************************************************/

	-cr /* Link using C conventions */

	#!/bin/bash

	# Build latest version of Emacs, version management with stow
	# OS: Ubuntu 14.04 LTS
	# version: 24.5
	# Toolkit: lucid

	# Warning, use updated version of this script in: https://github.com/favadi/build-emacs

	set -e

	#! /usr/bin/env ocamlscript
	Ocaml.ocamlflags := ["-thread"];
	Ocaml.packs := [ "core" ]
	--
	open Core.Std

	type term =
	\| Ident of string
	\| Lambda of string * term
	\| Apply of term * term

	(use '[clojure.core.match :only [match]])

	(defn evaluate [env [sym x y]]
	(match [sym]
	['Number] x
	['Add] (+ (evaluate env x) (evaluate env y))
	['Multiply] (* (evaluate env x) (evaluate env y))
	['Variable] (env x)))

	(def environment {"a" 3, "b" 4, "c" 5})