Mark M offlinemark

C99 List of Undefined Behavior

From N1256: (See http://port70.net/~nsz/c/c99/n1256.html#J.2)

A "shall" or "shall not" requirement that appears outside of a constraint is violated (clause 4).
A nonempty source file does not end in a new-line character which is not immediately preceded by a backslash character or ends in a partial preprocessing token or comment (5.1.1.2).
Token concatenation produces a character sequence matching the syntax of a universal character name (5.1.1.2).
A program in a hosted environment does not define a function named main using one of the specified forms (5.1.2.2.1).
A character not in the basic source character set is encountered in a source file, except in an identifier, a character constant, a string literal, a header name, a comment, or a preprocessing token that is never converted to a token (5.2.1).
An identifier, comment, string literal, character constant, or header name contains an invalid multibyte character or does not

A simple unix/linux daemon in Python

Source: http://www.jejik.com/articles/2007/02/a_simple_unix_linux_daemon_in_python/

Access: http://web.archive.org/web/20131025230048/http://www.jejik.com/articles/2007/02/a_simple_unix_linux_daemon_in_python/

by Sander Marechal

I've written a simple Python class for creating daemons on unix/linux systems. It was pieced together for various other examples, mostly corrections to various Python Cookbook articles and a couple of examples posted to the Python mailing lists. It has support for a pidfile to keep track of the process. I hope it's useful to someone.

(Note: This was originally from my blog post on AlexanderRobotics.com, but I brought that site down and wanted to keep this post alive since it's referenced by Stack Overflow).

Introduction

The beauty of the Arduino lies in its simplicity. A look under the covers of the Arduino and its IDE, however, reveals a fascinating chipset and an open, extensive toolchain.

	## Triggers (Bringing data into Zapier)
	### Sleep - polling
	https://api.fitbit.com/1/user/-/sleep/date/today.json

	### Activity - polling
	https://api.fitbit.com/1/user/-/activities/list.json?beforeDate=today&sort=desc&limit=10&offset=0

	## Scripting API
	see script.js

	#include <stdio.h>
	#include <unistd.h>
	#include <fcntl.h>
	#include <err.h>
	#include <time.h>
	#include <stdlib.h>

	int my_readline(const int fd, char *const buf, const size_t count);
	void my_print_lines(int fd, char *linebuf, size_t count);

	"""
	Example code for resetting the USB port that a Teensy microcontroller is
	attached to. There are a lot of situations where a Teensy or Arduino can
	end up in a bad state and need resetting, this code is useful for
	"""

	import os
	import fcntl
	import subprocess

	# First, Install Vagrant and Virtualbox then:

	# Create new project directory
	mkdir -p ~/Sites/newproject # Create new project directory
	mk ~/Sites/newproject # Go into your new project directory

	# Setup Vagrant
	vagrant init
	# Edit vagrant file box and box url to install Ubuntu, just like https://gist.github.com/fideloper/dab171a2aa646e86b782#file-vagrantfile-share-var-www-rb-L6-L8
	# Edit Vagrantfile to create a static IP address, just like https://gist.github.com/fideloper/dab171a2aa646e86b782#file-vagrantfile-share-var-www-rb-L10

	def clear_data(session):
	meta = db.metadata
	for table in reversed(meta.sorted_tables):
	print 'Clear table %s' % table
	session.execute(table.delete())
	session.commit()

	#!/usr/bin/env python

	import RPi.GPIO as gpio
	from time import sleep
	import re
	import sys

	gpio.setmode(gpio.BCM)
	red = 23
	yel = 24