This is so great! Writing toy kernel modules on your own is a super fun way to get into kernel programming. There's no danger of anything going wrong, especial

This is so great! Writing toy kernel modules on your own is a super fun way to get into kernel programming. There's no danger of anything going wrong, especially if you develop inside a VM. My partner wrote a kernel module for a talk I gave that rickrolls your file system -- it overrides the 'open' system call so that any time you open a '.mp3' file, it plays Rick Astley instead. (this requires you to have Rick Astley already on your computer =)) The source code for that (and a few other toy kernel modules) is at https://github.com/jvns/kernel-module-fun https://github.com/jvns/kernel-module-fun The rickroll module (by Kamal Marhubi) is the most well commented and fun: https://github.com/jvns/kernel-module-fun/blob/master/rickroll.c https://github.com/jvns/kernel-module-fun/blob/master/rickro... I wrote a blog post with more about this kernel-programming-for-fun philosophy: http://jvns.ca/blog/2014/01/04/4-paths-to-being-a-kernel-hacker/ http://jvns.ca/blog/2014/01/04/4-paths-to-being-a-kernel-hac... Of course, writing code for the mainline kernel is a responsible task, but writing kernel code on your own machine that nobody will ever run in production is a great way to learn, and I think it's made me a better programmer. A few concrete ways I think it's made me a better programmer: - I now understand the interface between kernel space and userspace much better (I use strace all the time to debug my regular userspace code!) - realizing that the Linux kernel is just written in C and it's something I can read (and understand! and change!) was a big deal for me - understanding the basics of the underlying operating system helps me reason about my programs better - I now feel like if I ran into an actual kernel bug or performance problem, it's something I could conceivably attempt to fix and understand, instead of hiding under the bed and saying OH NO THE KERNEL IT IS TOO HARD