HtwoO

ELF Format Cheatsheet

Introduction

Executable and Linkable Format (ELF), is the default binary format on Linux-based systems.

Compilation

HtwoO

Processing JSON using jq

jq is useful to slice, filter, map and transform structured json data.

Installing jq

On Mac OS

brew install jq

HtwoO

Google Sheet Functions - Cheatsheet

Based on https://support.google.com/docs/table/25273?hl=en

Array

Name	Syntax	Description
ARRAY_CONSTRAIN	ARRAY_CONSTRAIN(input_range, num_rows, num_cols)	Constrains an array result to a specified size.
BYCOL	BYCOL(array_or_range, LAMBDA)	Groups an array by columns by application of a LAMBDA function to each column.

HtwoO

GNU Make Cheatsheet

Based on https://www.gnu.org/software/make/manual/html_node/Quick-Reference.html

Directives

Directive	Description
define variable define variable = define variable := define variable ::= define variable += define variable ?= endef	Define multi-line variables.
undefine variable	Undefining variables.

HtwoO

#!/usr/bin/env bash

CA_NAME="Swan CA"
ROOT_NAME="Swan Root Cert"
# File path to save to
CA_DIR="self-signed.CA"
CA_KEY_FP="$CA_DIR/swan.key.pem"
CA_CRT_FP="$CA_DIR/swan.crt.pem"
mkdir -p "$CA_DIR"

HtwoO

#!/usr/bin/env bash

CA_NAME="Swan CA"
ROOT_NAME="Swan Root Cert"
# File path to save to
CA_DIR="self-signed.CA"
CA_KEY_FP="$CA_DIR/swan.key.pem"
CA_CRT_FP="$CA_DIR/swan.crt.pem"
mkdir -p "$CA_DIR"

HtwoO

#!/usr/bin/env bash

CA_NAME="Swan CA"
ROOT_NAME="Swan Root Cert"
# File path to save to
CA_DIR="self-signed.CA"
CA_KEY_FP="$CA_DIR/swan.key.pem"
CA_CRT_FP="$CA_DIR/swan.crt.pem"
CA_P12CRT_FP="$CA_DIR/swan.p12"
mkdir -p "$CA_DIR"

HtwoO

#!/usr/bin/env bash

CA_NAME="Swan CA"
ROOT_NAME="Swan Root Cert"
# File path to save to
CA_DIR="self-signed.CA"
CA_KEY_FP="$CA_DIR/swan.key.pem"
CA_CRT_FP="$CA_DIR/swan.crt.pem"
CA_P12CRT_FP="$CA_DIR/swan.p12"
mkdir -p "$CA_DIR"