David Marsh rdmarsh

Pi images on mac

On mac, dd needs to be a lowercase 'm'.

prepare disks

diskutil list
sudo diskutil unmount /dev/disk3s1

raspbian

Will automatically shred any inserted disks without warning.

Designed for raspberry pi.

sudo cp 91-shred_usb_device_rule.rules /etc/udev/rules.d/
sudo chmod 644 /etc/udev/rules.d/91-shred_usb_device_rule.rules
sudo cp shred_usb_device.sh /usr/local/bin/shred_usb_device.sh
sudo chmod 755 /usr/local/bin/shred_usb_device.sh

write last 2MB of disk to a file

# tailfile="taildisk-`date "+%Y%m%dT%H%M%S"`.dat"
# dd if=/dev/sda of=${tailfile} bs=512 skip=$(( $(blockdev --getsz /dev/sda) - 4096 ))
4096+0 records in
4096+0 records out
2097152 bytes (2.1 MB, 2.0 MiB) copied, 0.0185222 s, 113 MB/s
# ls -lah ${tailfile}

-rw-r----- 1 root root 2.0M Jul 16 11:08 taildisk-20160716T110821.dat

	int speakerPin = 9;
	int length = 15; // the number of notes
	char notes[] = "ccggaagffeeddc "; // a space represents a rest
	int beats[] = { 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 4 };
	int tempo = 300;

	void playTone(int tone, int duration) {
	for (long i = 0; i < duration * 1000L; i += tone * 2)
	{
	digitalWrite(speakerPin, HIGH);

	zc/one/two/three/four
	zc/one/two/three
	zc/one/two
	zc/one

	# Raspberry Pi Pico and GLowBit Rainbow
	# Combination of sample code from
	# GloBit: https://core-electronics.com.au/tutorials/how-to-use-ws2812b-rgb-leds-with-raspberry-pi-pico.html
	# Temperature: https://github.com/geerlingguy/baby-safe-temp/blob/master/main.py

	import array, utime
	from machine import Pin
	import rp2

	# Get the temperature from the internal RP2040 temperature sensor.

	#!//bin/bash

	URL_LIST='/home/pi/kids-internet.dat'

	case ${1} in
	block)
	FLAG=''
	;;
	unblock)
	FLAG='--delmode'

	#!/usr/bin/env bash

	#
	# Makes list of twitter accounts that should be (un)followed. To use; Create a
	# twitter list, add primary users to it and set primarylist variable to list
	# name You will get three lists
	#
	# * groupies: these accounts follow you, but you don't follow them
	#
	# * to follow: these accounts have a relation with your primary accounts, but

	#!/usr/bin/env bash

	#produces a dot graph for homebrew dependencies
	#run using `./brew-tree.sh \| dot -Tpdf -o brew-tree.pdf`

	set -e #exit immediately if a simple command exits with a non-zero status
	set -u #treat unset variables as an error when performing parameter expansion
	set -o pipefail #exit status of last non-zero exit code is returned

	echo "digraph brew {"

	#!/usr/bin/env perl -w

	### 2016-06-01:davidm:simple program to center text on a line

	use strict;
	use warnings;
	use POSIX;

	#f1: string
	#f2: total width