Sometimes we in the development of the kernel driver when there is a lot of need to increase the switch control feature, when debug, and sometimes need to improve debug efficiency, do not want to go manually change the code, this time you can use procfs, to achieve control by the flag procfs switch.
In many types of Unix computer systems, it is the procfs process file system abbreviation (file system) comprising a pseudo file system (dynamically generated file system startup) for passing the kernel information access process. This file system is often mounted to / proc directory . Since the / proc is not a real file system, it does not take up storage space, just take up limited memory.