A very good read, thanks for taking the time to put pen to paper and sharing the little useful scripts and tricks. There's a world of heavy-handed hacking out there to use. I used to build hundreds of patched kernels or glibcs to simulate complex systems behaviour (failing read()/write(), incomplete fsync, syscalls in general or the network stack erroring out in all possible ways...) and scenarios of those. Happy to see this explained so simply.