ced4568andClaude Sonnet 5
15b616274b
Adds all 6 ROOT 01 modules (how computers run software, the shell, filesystem navigation, files & text, processes, users & permissions foundations), each with a real lesson, demonstration/guided exercise, knowledge check where warranted, a hands-on Lab, and a reflection — 35 activities, 29 new content files. Adds 6 new hands-on Linux scenarios (linux-inspect-hardware, linux-shell-basics, linux-filesystem-navigation, linux-files-and-text, linux-process-management, linux-permissions-foundations) plus 2 MCQ scenarios, using the existing generic scenario/ validation engine (docs/ROOT_FOUNDATIONS_LAB_STRATEGY.md §1) — every one tested end-to-end via the real scenario setup/validate API, including negative tests confirming they correctly FAIL when not actually solved (e.g. the process-management scenario fails while the target process is still running; the permissions scenario is tested against a real `su - labuser` denial). Wires rootnode-linux-foundations-assessment (2 required + 4 random-draw scenarios) using the existing Phase 3B assessment engine. Adds a real, server-side ROOT 01->02->03->04->05 course prerequisite chain (courses.prerequisites) — verified live on two students: one who completed ROOT 01 sees ROOT 02 unlock; a fresh student sees ROOT 02 correctly locked while 03/04/05 stay vacuously satisfied (their own prerequisite courses are still empty). ROOT 06+ and the Capstone are unaffected. Co-Authored-By: Claude Sonnet 5 <[email protected]>
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Knowledge Check: Processes
1. What does a PID identify?
Answer: One specific running instance of a program — the kernel's unique identifier for that process, distinct from every other running process, even other copies of the same program.
2. What's the actual difference between kill <pid> and kill -9 <pid>?
Answer: Plain kill sends SIGTERM, a polite request the process can choose to handle (clean
up, then exit). kill -9 sends SIGKILL, which the kernel enforces immediately with no chance
for the process to react — an escalation for when SIGTERM is ignored, not the default choice.
3. You want to confirm a process is still running WITHOUT affecting it in any way. What do you use?
Answer: kill -0 <pid> — sends no real signal, only checks whether the PID still exists.
4. Why might understanding processes matter for understanding containers later?
Answer: A container is, underneath, mostly an isolated process (or small process tree) — a container "exiting" is really its main process exiting, the exact same event this module's Lab causes on purpose.
Instructor Notes
Facilitation: Question 2 is worth confirming explicitly — "kill -9 by default" is a common, worth-correcting habit.
Approximate timing: 5 minutes.