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]>
53 lines
2.4 KiB
Markdown
53 lines
2.4 KiB
Markdown
# Files and Text
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## Basic file operations
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- `touch <file>` — create an empty file (or update its timestamp if it exists)
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- `mkdir <dir>` — create a directory (`-p` creates any missing parent directories too)
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- `cp <src> <dst>` — copy a file
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- `mv <src> <dst>` — move OR rename a file (Linux treats renaming as "moving to a new name in
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the same place")
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- `rm <file>` — delete a file (`-r` for a directory, `-f` to skip confirmation — dangerous
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combined: `rm -rf` deletes without asking, permanently)
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## Reading text
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- `cat <file>` — print the whole file at once
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- `less <file>` — page through a file interactively (press `q` to quit) — the right tool for
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anything too long to read in one screen
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- `head <file>` / `tail <file>` — the first/last 10 lines by default (`-n 20` for a different
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count); `tail -f` follows a file live as new lines are appended — exactly how you'd watch a
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log file update in real time
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## Searching text: `grep`
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`grep PATTERN file` prints only the lines matching PATTERN. This is one of the most-used
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commands in real operations work — "find the lines that matter" beats "read everything."
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## Pipes and redirection: composing commands
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- **A pipe (`|`)** sends one command's output as the next command's input:
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`cat app.log | grep ERROR` — read the file, then filter it.
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- **Redirection (`>`)** sends a command's output into a file instead of the screen (overwriting
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it): `grep ERROR app.log > errors.txt`. `>>` appends instead of overwriting.
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## stdout vs. stderr
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A command actually has TWO separate output streams: **stdout** (normal output) and **stderr**
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(error messages), even though both print to your screen by default. This is why
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`command 2>/dev/null` (redirecting stream `2`, stderr, to nowhere) can suppress error noise
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while still showing normal output — you'll use exactly this pattern in later Labs.
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## Instructor Notes
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**Lesson goal:** Build real fluency composing small commands together — this is the single
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highest-leverage Linux skill for troubleshooting work later in ROOT_.
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**Approximate timing:** 15 minutes read; 10 minutes live.
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**Common misconception to watch for:** students often don't realize stdout/stderr are separate
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streams until they see `2>/dev/null` change what's suppressed — worth demonstrating live.
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**Demo idea:** run a command that produces both real output and an error in the same call
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(e.g. `ls /etc /nonexistent`) and show how `2>/dev/null` changes what appears.
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