Build a readback habit after each file change.
Mission 15
Edit and verify
Create a runbook, count its lines, and inspect metadata after saving.
Nano and editing
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learner@clairos:/home/learner $
Unix ops lab: type a command, press Enter
Lesson support
What to notice while you play.
Save a few short lines so wc has something to count.
Verification catches wrong paths, failed saves, and stale assumptions.
- Trusting an edit without reading it back.
- Checking the wrong filename.
Reference
Commands in this lesson.
nano <file>
Open a browser-only fake nano editor.
cat <file>
Print text file contents.
wc [-l] <file>
Count lines, words, and characters.
stat <path>
Show fake file details.