Displaying the process parent tree | LinuC Level 1 101 Exam original practice question

1.01.4Basic

Find which service process created worker processes.

Display the process hierarchy with PIDs.

Which command is appropriate?

Hint 1: Focus on the requirement

The investigation needs parent-child relationships and process IDs rather than CPU statistics.

Hint 2: Key terms

Review the short definitions before comparing the process and job-control choices.

pstree: A command that displays processes in parent-child tree form.
PPID: The process ID of the parent that created or launched a process.
Process tree: A hierarchy showing how processes descend from other processes.
-p: The pstree option that includes process IDs in the tree.

Detailed explanation

Incorrectps -p tree

Incorrect. ps -p expects a PID list; tree is not the process-tree option in this form.

Correctpstree -p

Correct. pstree -p shows the process hierarchy and PIDs.

Incorrectpgrep --parent-all

Incorrect. pgrep has no --parent-all option for this display.

Incorrectuptime -p

Incorrect. uptime reports system uptime and load.

An example you can run in a temporary verification environment.

pstree -p $$ | head

現在shellを起点としたprocess tree

Environment: psmisc系pstree
Use a disposable process or test shell when checking lifecycle commands.
Exact output and option names can vary slightly by distribution and tool version.

Foundation review

A process tree explains creation relationships; it is different from a flat process listing or a load monitor.

Start at a known PID or shell when the complete process tree is too large to interpret.

Question IDKL-101-362

Environmentpsmisc系pstree

Last technical review2026-08-13

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