Understanding /proc: Part 2
As it was shown in the first installment of the Understanding /proc series, the /proc filesystem can be extremely useful when it comes to finding out about the processes running on your Linux system (which might have something to do with why the kernel developers decided to name it 'proc'). But /proc is also handy when it comes to learning about the devices on your system. While it is currently being deprecated in favor of the /sys filesystem for device information, /proc can still provide some valuable insight as to what you have attached to (or inside of) your computer.
Before we continue, I think a little clarification is in order. Just what do I mean by a device?
Some would say that a device is anything with a driver. While this would include the expected physical devices like a USB controller, hard drive, or a network card, there are some objects with drivers that aren't physical devices like the null device (/dev/null) or the loopback device ('lo'). Others would argue that a device is only a physical device that you can take, pick apart, or basically just a tangible object.
For the purposes of this article, I choose to go with the latter definition, and not include the so-called "virtual" devices. These will be covered in the fourth and final installment of this series, covering miscellaneous things that one can do with /proc, as well as a few practical 'real-world' scenarios.