`pstree` - display a tree of processes

pstree [-p] [-a] [-u] [-A] [pid|user]

Options you will use

-p: Show PIDs. Also disables the merging of identical branches.
-a: Show command line arguments.
-u: Show uid transitions.
-A: Use ASCII line drawing characters.
-s, --show-parents: Show the parents of the given process too.
-p, --show-pids: Show PIDs.

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