If you've written any amount of bash code, you've likely come across the trap command. Trap allows you to catch signals and execute code when they occur. Signals are asynchronous notifications that are sent to your script when certain events occur. Most of these notifications are for events that you hope never happen, such as an invalid memory access or a bad system call. However, there are one or two events that you might reasonably want to deal with. There are also "user" events available that are never generated by the system that you can generate to signal your script. Bash also provides a psuedo-signal called "EXIT", which is executed when your script exits; this can be used to make sure that your script executes some cleanup on exit.

Doc Searls and Katherine Druckman talk to Yiftach Shoolman of Redis Labs about Redis, Open Source licenses, company culture and more. Listen to the podcast here.

Steven Rostedt wanted to do a little housekeeping, specifically with the function tracing code used in debugging the kernel. Up until then, the kernel could enable function tracing using either GCC's -pg flag or a combination of -pg and -mfentry. In each case, GCC would create a special routine that would execute at the start of each function, so the kernel could track calls to all functions.

The kernel this. The kernel that. People often refer to one operating system's kernel or another without truly knowing what it does or how it works or what it takes to make one. What does it take to write a custom (and non-Linux) kernel?

Enterprise comes to the micro server.

I have spent the first three parts of this series describing the evolution and current state of Flash storage. I also described how to configure an NVMe over Fabric (NVMeoF) storage network to export NVMe volumes across RDMA over Converged Ethernet (RoCE) and again over native TCP.