Open Source Computing

Week of Feb 17

Week 6:

Monday

Each team should select a reporter, who is supposed to file a brief report on Sakai every Friday. Usually this is one person, but it can be a rotating position. Only one person on each team has to file the report.

Reports should discuss progress, eg on selecting a project, on deciding on what changes to make, on understanding the code, on implementing your changes.

Open Source as a business

    "Open Core"

    Scott McNealy, former CEO of Sun Microsystems: "Open Source is free like a puppy is free"

Wednesday

Git

Android calculator: much more complicated than you thought. chadnauseam.com/coding/random/calculator-app.

The designer, Hans-J Boehm, didn't use floating-point arithmetic. Instead he used a mix of:

As a result, sin(pi) displays as 0, not 0.0000000, and 10^100 + 1 - 10^100 displays as 1.

Open Source as a business

Google and Android, Chromium

Linux history

What made Linux such a successful open-source project? Why did Linux beat BSD?
The email from Linus Torvalds to Mauro Carvalho illustrates two things:
  1. Torvalds' somewhat abusive style
  2. Torvalds' firm no-regression policy: user code that used to work should never be broken by a kernel update.

How do these factors play out in the success of Linux?

A third factor is Torvalds' policy on contributions: all are welcome, but they start out as non-mainline extensions, patches or modules.

2020 Linux Kernel Report

2022 Linux Kernel Report

386BSD

LibreOffice, bash