procfs

procfs or the proc file system, is a virtual filesystem that provides information about the system. Its data can be accessed with typical filesystem navigation commands such as ls, cat, cd, etc.

procfs is common on Linux and FreeBSD systems. In Linux, the ps command is commonly implemented using data contained within procfs.

https://docs.kernel.org/filesystems/proc.html

https://gitlab.com/procps-ng/procps

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