Michael Lockhart sinewalker

I found the SICP available for Emacs in the MELPA. It's a conversion of the HTML version made available for free by MIT, into Texi and then generated into Info.

The source for the MELPA is available on github: https://github.com/webframp/sicp-info

There was one open Issue: webframp/sicp-info#2 so I forked the master repo and created a PR from the correction to that, plus regenerating the whole Info as this appears not to have been done in 4 years.

Hopefully my PR will get accepted. If not, then I can still use my own fork, I'll just have to learn how to install a local package with Spacemacs, which I think isn't too hard.

Great posibilities if we could have tmux on our servers:

http://www.howardism.org/Technical/Linux/tmux.html

http://tmuxp.readthedocs.io/en/latest/about_tmux.html

http://perlstalker.vuser.org/blog/2012/10/16/emacsclient-and-tmux/

but tmux isn't available in the standard Scientific/CentOS repositories

Convert a Unix timestamp into human-readable format:

GNU: date -date='@1501768813'
BSD: date -r 1501768813

Convert the other way

Current date/time as Unix timestamp: date +%s
A specific date/time (assumes current timezone):

I was using this pipeline:

grep -c processor /proc/cpuinfo

However there's a better way: nproc

and for a good summary of CPU info from /sys and /proc/cpuinfo use lscpu which has options to produce parseable output for pipelines.

Need to take %APPDATA% directory data to another PC? For example Minecraft game saves to take in to a school for projects, or to a friend's house. The tricky part is: %APPDATA% has a different location depending on the version of Windows. Yay Microsoft, thanks once again.

The good news is that many Windows programs do use the environment variable to locate this folder, so you can just override it and launch your game or whatever from a .cmd / .bat file.

In the case of Minecraft on a USB:

Make a folder structure on the USB drive for it (assume E: is the USB):
- E:\Minecraft
- E:\Minecraft\bin

E:\Minecraft\data

	import pygame, random
	pygame.init();
	scr=pygame.display.set_mode([640,400])
	df=pygame.display.flip; rnd=random.randrange; draw=pygame.draw
	scr.fill([0,0,255]); df()
	while True:
	draw.aaline(scr, [rnd(255),rnd(255),rnd(255)],
	[rnd(640),rnd(400)],
	[rnd(640),rnd(400)]); df()

	#!/usr/bin/env python
	# usage: echo "My QR Text"\|makeQR.py > myqr.png
	# see http://alecthegeek.github.io/2013/04/28/creating-qr-codes-on-python.html
	import sys
	import qrcode
	qrcode.make("".join(sys.stdin.readlines())).save("/dev/stdout","png")

	# I used this code within an IPython session to clean up all the missing ID3 tags from my MP3 collection.
	# They had gone missing years ago when I down-sampled them to fit on an old phone, and then lost the originals.
	# Fortunately I named the files themselves with the basic details (artist, date, title and so on) so it was possible to
	# recover the tags... It sat on my to-do list for years but now I finally did it.

	# I used the Python library "EyeD3" (get it?): https://pypi.python.org/pypi/eyeD3
	# This requires Python 2.7, which has some interesting quirks for Unicode, a bit of a pain since I had named my MP3s
	# with utf8 characters. What I've come up with mostly works. When it doesn't I had to resort to manually editing (using
	# Clementine).

	# required utilities
	required=(
	grep
	awk
	curl
	jq
	)

	missing=()

	base=$(cd -- "$(dirname -- "$0")"; pwd -P)
	source $base/util/platform.sh
	source $base/util/check-required-utilities.sh