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# Hello, and welcome to makefile basics.
#
# You will learn why `make` is so great, and why, despite its "weird" syntax,
# it is actually a highly expressive, efficient, and powerful way to build
# programs.
#
# Once you're done here, go to
# http://www.gnu.org/software/make/manual/make.html
# to learn SOOOO much more.
@hubgit
hubgit / README.md
Last active May 2, 2024 10:55
Remove metadata from a PDF file, using exiftool and qpdf. Note that embedded objects may still contain metadata.

Anonymising PDFs

PDF metadata

Metadata in PDF files can be stored in at least two places:

  • the Info Dictionary, a limited set of key/value pairs
  • XMP packets, which contain RDF statements expressed as XML

PDF files

@chaitanyagupta
chaitanyagupta / _reader-macros.md
Last active April 29, 2024 09:09
Reader Macros in Common Lisp

Reader Macros in Common Lisp

This post also appears on lisper.in.

Reader macros are perhaps not as famous as ordinary macros. While macros are a great way to create your own DSL, reader macros provide even greater flexibility by allowing you to create entirely new syntax on top of Lisp.

Paul Graham explains them very well in [On Lisp][] (Chapter 17, Read-Macros):

The three big moments in a Lisp expression's life are read-time, compile-time, and runtime. Functions are in control at runtime. Macros give us a chance to perform transformations on programs at compile-time. ...read-macros... do their work at read-time.

@0XDE57
0XDE57 / config.md
Last active April 18, 2024 04:36
Firefox about:config privacy settings

ABOUT

about:config settings to harden the Firefox browser. Privacy and performance enhancements.
To change these settings type 'about:config' in the url bar. Then search the setting you would like to change and modify the value. Some settings may break certain websites from functioning and rendering normally. Some settings may also make firefox unstable. I am not liable for any damages/loss of data.

Not all these changes are necessary and will be dependent upon your usage and hardware. Do some research on settings if you don't understand what they do. These settings are best combined with your standard privacy extensions (HTTPS Everywhere No longer required: Enable HTTPS-Only Mode, NoScript/Request Policy, uBlock origin, agent spoofing, Privacy Badger etc), and all plugins set to "Ask To Activate".

@briansmith
briansmith / how-to-generate-and-use-private-keys-with-openssl-tool.md
Last active April 11, 2024 17:02
How to generate & use private keys using the OpenSSL command line tool

How to Generate & Use Private Keys using OpenSSL's Command Line Tool

These commands generate and use private keys in unencrypted binary (not Base64 “PEM”) PKCS#8 format. The PKCS#8 format is used here because it is the most interoperable format when dealing with software that isn't based on OpenSSL.

OpenSSL has a variety of commands that can be used to operate on private key files, some of which are specific to RSA (e.g. openssl rsa and openssl genrsa) or which have other limitations. Here we always use

@spion
spion / a-warning.md
Last active March 25, 2024 03:01
C++ versus V8 versus luajit versus C benchmark - (hash) tables

Warning

This benchmark has been misleading for a while. It was originally made to demonstrate how JIT compilers can do all sorts of crazy stuff to your code - especially LuaJIT - and was meant to be a starting point of discussion about what exactly LuaJIT does and how.

As a result, its not indicative of what its performance may be on more realistic data. Differences can be expected because

  1. the text will not consist of hard-coded constants
@chrisdone
chrisdone / AnIntro.md
Last active March 24, 2024 21:13
Statically Typed Lisp

Basic unit type:

λ> replTy "()"
() :: ()

Basic functions:

@atoponce
atoponce / gist:07d8d4c833873be2f68c34f9afc5a78a
Last active March 19, 2024 17:24 — forked from tqbf/gist:be58d2d39690c3b366ad
Cryptographic Best Practices

Cryptographic Best Practices

Putting cryptographic primitives together is a lot like putting a jigsaw puzzle together, where all the pieces are cut exactly the same way, but there is only one correct solution. Thankfully, there are some projects out there that are working hard to make sure developers are getting it right.

The following advice comes from years of research from leading security researchers, developers, and cryptographers. This Gist was [forked from Thomas Ptacek's Gist][1] to be more readable. Additions have been added from

@andrejbauer
andrejbauer / topology.v
Last active November 28, 2023 19:40
How to get started with point-set topology in Coq. This is not actually how one would do it, but it is an intuitive setup for a classical mathematician.
(* How do to topology in Coq if you are secretly an HOL fan.
We will not use type classes or canonical structures because they
count as "advanced" technology. But we will use notations.
*)
(* We think of subsets as propositional functions.
Thus, if [A] is a type [x : A] and [U] is a subset of [A],
[U x] means "[x] is an element of [U]".
*)
Definition P (A : Type) := A -> Prop.
@qnighy
qnighy / sprintf.v
Created August 12, 2012 02:14
Coqでsprintf
Require Import Ascii String.
Require Import List.
Require Import Arith NArith ZArith Omega.
Require Import Recdef Program.Wf.
Require Import Zdiv.
(* Local Notation "a :: b" := (String a b) : string_scope. *)
Definition Z_to_digit(n:Z):ascii :=
match n with