Ionizing Ionizing

Podman Cheatsheet

This cheat sheet covers the commands used for working with Podman, a popular tool for managing containers. Podman commands are mostly compatible with Docker. As stated on the Podman landing page, "Podman is a daemonless, open source, Linux native tool designed to make it easy to find, run, build, share and deploy applications using Open Containers Initiative (OCI) Containers and Container Images."

Image repositories

# List all local images
podman images
# Remove (forced) a local image from the local cache

Using TikZ in Markup Languages

Introduction

So consider the tikz code at listing tikz-eg1 and figure Tikz-out1:

Update 25 April 2020:

Many thanks to @KZL1992 @tomslominski @ptrofi @n-thumann for recent comments on their experiences with 20.04 and Parallels 13/14/15, especially the subsitution of the latest prl-tools-lin.iso for older Parallels to get it going.

First off, credit goes to github.com/rudolfratusinski for leading the way here.

https://gist.github.com/rudolfratusinski/a4d9e3caff11a4d9d81d2e84abc9afbf

Workarounds for Netflix and the blocking of Hurricane Electric IPv6 tunnels

The dreaded "You seem to be using an unblocker or proxy." error message. Cool story bro.

This gist was essentially created out of my own rant about Netflix being hostile to IPv6 tunnel services since June 2016. You are welcome to read my opinion on the matter, this is the more technical side to the issue and how to combat it within your own network.

Since I wrote this, various GitHub users have contributed their thoughts and ideas which has been incorporated into this gist. Thank you to everyone who have contributed their own methods and implementations.

The problem

Netflix now treats IPv6 tunnel brokers (such as Hurricane Electric) as proxy servers. A while ago it became apparent to users and Netflix that somewhat by accident, IPv6 tunnel users were being served content outside of their geolocation because of the way Netflix was identifyi

Revert the full commit

Sometimes you may want to undo a whole commit with all changes. Instead of going through all the changes manually, you can simply tell git to revert a commit, which does not even have to be the last one. Reverting a commit means to create a new commit that undoes all changes that were made in the bad commit. Just like above, the bad commit remains there, but it no longer affects the the current master and any future commits on top of it.

git revert {commit_id}

About History Rewriting

Delete the last commit

Deleting the last commit is the easiest case. Let's say we have a remote origin with branch master that currently points to commit dd61ab32. We want to remove the top commit. Translated to git terminology, we want to force the master branch of the origin remote repository to the parent of dd61ab32:

	SPC
	SPC: find file
	, switch buffer
	. browse files
	: MX
	; EX
	< switch buffer
	` eval
	u universal arg
	x pop up scratch

	\documentclass{article}
	\usepackage{tikz}
	\begin{document}
	\begin{tikzpicture}
	\draw[domain = 0:2.2, smooth, variable=\x, blue, samples = 221]
	plot ({\x}, {sqrt(\x)})
	node[anchor = west] {$ y = \sqrt x $};
	\end{tikzpicture}
	\end{document}

	(defconst fn/haskell-file-extension ".hs"
	"The de facto haskell file extension.")

	(defun fn/add-haskell-file-extension (name)
	"Add the extension of .hs to a file or buffer NAME."
	(if (string/ends-with name fn/haskell-file-extension)
	name (concat name fn/haskell-file-extension)))

	(defvar fn/org-haskell-mode-hook nil
	"Hook when buffer is haskellized.")

	\documentclass[twocolumn]{article}
	\usepackage{mwe}
	\usepackage{widetext}
	\begin{document}
	\blindtext
	\begin{widetext}
	\[
	E = mc^2.
	\]
	\end{widetext}