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]>
32 lines
1.4 KiB
Markdown
32 lines
1.4 KiB
Markdown
# Guided Exercise: Predict the Exit Code Before You Run It
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This is a paper exercise — commit to an answer before checking it in the Lab.
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## Your task
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For each command below, predict whether its exit code will be `0` (success) or non-zero
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(failure), and why:
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1. `cat /etc/hostname` (a file that exists)
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2. `cat /etc/does-not-exist-at-all` (a file that doesn't)
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3. `grep root /etc/passwd` (a pattern that's very likely present)
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4. `grep zzz-not-a-real-user /etc/passwd` (a pattern that's very likely absent)
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5. `mkdir /tmp/already-exists && mkdir /tmp/already-exists` (running the same `mkdir` twice)
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## A worked shape to check yourself against
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1. `0` — the file exists and is readable.
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2. Non-zero — the file doesn't exist, `cat` fails.
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3. `0` — `grep` succeeds (exit 0) when it finds at least one match.
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4. Non-zero (specifically `1`) — `grep` "fails" when it finds NO matches, even though nothing
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went technically wrong. This is a common surprise: `grep`'s exit code means "did I find a
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match," not "did an error occur."
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5. The SECOND `mkdir` fails (non-zero) — the directory already exists. The first one succeeds.
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## Instructor Notes
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**Facilitation:** Item 4 is the one worth pausing on — many students assume "no error message"
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means "exit code 0," and `grep`'s no-match convention is a good early counter-example.
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**Approximate timing:** 8-10 minutes live discussion; 5 minutes self-paced.
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