Having a history of shell commands is a great idea. It is, of course, enormously handy when you have to run something repetitively or you make a simple mistake that needs correction. However, as I’ve mentioned in the past, bash history isn’t without its problems. For one thing, by default, you don’t get history in one window from typing in another window. If you use a terminal multiplexer or a GUI, you are very likely to have many shells open. You can make them share history, but that comes with its own baggage. If you think about it, we have super fast computers with tons of storage compared to the “old days,” yet shell history is pretty much the same as it has been for decades. But [Rcaloras] did think about it and created Bashhub, a history database for bash, zsh, and probably some other shells, too.
You might think you don’t need anything more than what you have, and, of course, you don’t. However, Bashhub offers privately stored and encrypted history across machines. It also provides context about commands you’ve executed in the past. In other words, you can see the directory you were in, the exact time and date, the system you were on, and the last return code of the command.
Here’s a simple FET circuit that lets you switch power to, say, a USB port, kind of like a valve that interrupts the current flow. This circuit uses a P-FET – to turn the power on, open the FET by bringing the GATE signal down to ground level, and to switch it off, close the FET by bringing the GATE back up, where the resistor holds it by default. If you want to control it from a 3.3 V MCU that can’t handle the high-side voltage on its pins, you can add a NPN transistor section as shown – this inverts the logic, making it into a more intuitive “high=on, low=off”, and, you no longer risk a GPIO!
