As I’m looking for a fallback connection for my home fiber, I’ve been experimenting with 4G and 5G at home. I’ll write down my discoveries little by little across multiple posts. The first router: “why am I stuck at 10 Mbps?” I started with a basic 4G router, the MERCUSYS MB110-4G. The connection was underwhelming: I could barely reach ~10 Mbps down / ~10 Mbps up, even though the box claims up to 150 Mbps. ...
How Inotify works - part 2 - How a system call is called
In this blog post we will try to understand how Inotify can be called from the user space to the kernel space, moving from our process to the libc, the c standard library. If we invoke strace in our Linux shell with a program as argument, we will see the system call called by the process passed as an argument. strace is a Linux command that records the system calls done by our program while executing, from the user space to the kernel space. It prints to screen the system call name, the parameters passed to the system call and the system call return value. ...
How Inotify works - part 1
While reading the The linux programming interface book I finally dived deep in Inotify and how it works. Basically inotify is a notification system for events happening on files/directory like access, changes, edit and so on. It was meant to replace dnotify, an older notification system, that used signals to notify about changes. Inotify is based on file descriptor opened when you watch a file and a read syscall to check the status of the file. ...