shawwwn

# µPing (MicroPing) for MicroPython
# copyright (c) 2018 Shawwwn <shawwwn1@gmail.com>
# License: MIT

# Internet Checksum Algorithm
# Author: Olav Morken
# https://github.com/olavmrk/python-ping/blob/master/ping.py
# @data: bytes
def checksum(data):
    if len(data) & 0x1: # Odd number of bytes

allenyllee

#!/bin/bash

# install qemu utils
sudo apt install qemu-utils

# install nbd client
sudo apt install nbd-client

ekreutz

Ansible variable precedence

Source: http://docs.ansible.com/ansible/latest/playbooks_variables.html#variable-precedence-where-should-i-put-a-variable

From least to most important

• command line values (for example, -u my_user, these are not variables)
• role defaults (defined in role/defaults/main.yml)
• inventory file or script group vars
• inventory group_vars/all

whitslack

Early Userspace without Initramfs

If you've built your own kernel with all necessary storage-controller and file-system drivers built in, then you may have no need of an early userspace environment. However, if you want to do anything non-trivial with your root file system (LVM, LUKS, etc.), then you need an early userspace to set up and mount it. The traditional mechanism for this is initramfs, but building and maintaining an initramfs image is awkward and tiresome. Initramfs is a sledgehammer when, nine times out of ten, all you need is a screwdriver. This guide details a method of booting into an early userspace environment located in an ordinary file system on a physical disk partition, where an init script in this environment in turn sets up and mounts the real root file system and pivots into it.

Setting Up the Basic Environment

In order to employ this method of booting your system, you will need a traditional (non-LVM) disk partition containing a file system that your kernel can mount without