| /* | |
| * Copyright 2020 Andrei Pangin | |
| * | |
| * Licensed under the Apache License, Version 2.0 (the "License"); | |
| * you may not use this file except in compliance with the License. | |
| * You may obtain a copy of the License at | |
| * | |
| * http://www.apache.org/licenses/LICENSE-2.0 | |
| * | |
| * Unless required by applicable law or agreed to in writing, software |
| $ cat > main.tf | |
| provider "null" { | |
| version = "2.1.1" | |
| } | |
| ^D | |
| $ terraform init | |
| Initializing the backend... | |
| Initializing provider plugins... |
| ARG go_version=1.17 | |
| ARG alpine_version=latest | |
| FROM golang:${go_version}-alpine AS builder | |
| ARG GOOS=linux | |
| ARG GOARCH=amd64 | |
| ENV GOOS=${GOOS} | |
| ENV GOARCH=${GOARCH} |
I remembered the chvt (change foreground virtual terminal) command, so that seems
like a good place to start. I looked at BusyBox's implementation in
console-tools/chvt.c, hoping that it would be small enough to skim through.
At 33 lines, with only 9 lines containing code I wasn't disappointed.
The call to console_make_active looks interesting. console_make_active can
be found in libbb/get_console.c:
| class Binary < Formula | |
| desc "" | |
| homepage "" | |
| head do | |
| url "", branch: "main" | |
| depends_on "go@1.14" => :build if build.head? | |
| end |
The Linux kernel is written in C, so you should have at least a basic understanding of C before diving into kernel work. You don't need expert level C knowledge, since you can always pick some things up underway, but it certainly helps to know the language and to have written some userspace C programs already.
It will also help to be a Linux user. If you have never used Linux before, it's probably a good idea to download a distro and get comfortable with it before you start doing kernel work.
Lastly, knowing git is not actually required, but can really help you (since you can dig through changelogs and search for information you'll need). At a minimum you should probably be able to clone the git repository to a local directory.
| // Using the && (logical AND) operator. | |
| #define pm_driver_has_callback(__device, __callback) \ | |
| ((__device)->driver && (__device)->driver->pm && (__device)->driver->pm->__callback) | |
| #define pm_driver_do_callback(__device, __callback) \ | |
| (pm_driver_has_callback(__device, __callback) ? (__device)->driver->pm->__callback(__device) : 0) | |
| // Using a statement expression to avoid using ternary operator... |
| Vagrant.configure("2") do |config| | |
| config.vm.box = "ubuntu/focal64" | |
| config.vm.provider "virtualbox" do |vb| | |
| vb.customize [ "modifyvm", :id, "--uartmode1", "file", "/dev/null" ] | |
| end | |
| end |
Unless otherwise noted (either in this file or in a file's copyright section) the contents of this gist are Copyright ©️2020 by Christopher Allen, and are shared under spdx:Creative Commons Attribution Share Alike 4.0 International (CC-BY-SA-4.) open-source license.
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