Intro Bubbletea is a framework with a philosophy based on The Elm Architecture: Making it simple, it breaks into three parts: Model: the state of your application View: a way to turn your state into something to display Update: a way to update your state based on messages The framework’s runtime manages everything else: from messages orchestration to low-level rendering details. Example Let’s say you want to create the classic to-do list: ...
🙀 Something breaks If you use linux running some applications you could have seen sometimes a similar error message: [1] 24975 segmentation fault (core dumped) what’s meaning and how it can be useful ? Let’s dig it out. 🧪 Lab Setup To make a proper case study, we need a crashing program. Of course they are very rare nowadays 😁 so we just create a new one ourself, showing off our worst C coding bad skills and practices. ...
An old find I found an old cubieboard3 (cubietruck) collecting dust in a drawer, so I took the chance to try out Rust cross compilation and collect here some notes about the process. Here’s the baby: Give it a penguin First of all, I installed an ARM linux distro on a MicroSD card and started the device: [user@arm ~]$ cat /proc/cpuinfo processor : 0 model name : ARMv7 Processor rev 4 (v7l) BogoMIPS : 50.52 Features : half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xc07 CPU revision : 4 processor : 1 model name : ARMv7 Processor rev 4 (v7l) BogoMIPS : 50.52 Features : half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm CPU implementer : 0x41 CPU architecture: 7 CPU variant : 0x0 CPU part : 0xc07 CPU revision : 4 Hardware : Allwinner sun7i (A20) Family Revision : 0000 So our device is ARM model v7l ; this means is a 32bit CPU, if you are curious there’s also a reference manual around. Now we will work from a development machine. ...
Prelude This is a followup from my previous post and a sort of continuation on the series of the topic, where we are exploring ways to make our test system more “unreliable” in order to observe if our applications behave nicely under challenging and not-ideal environments. In this article we are going to explore some linux technologies: Network Namespaces (netns) Virtual Ethernet Devices (veth) Network Emulation (netem) scheduling policy The goal is to setup a virtual network link inside our system, make the two network devices talk each other and then simulate a bad/slow/glitchy/flaky communication to test how applications behave under difficult conditions. ...