Run printf terminal-ready | tee lab/terminal-ready.txt.
printf terminal-ready | tee lab/terminal-ready.txt
Mission 306
Output capture contract
Print a predictable marker, capture it, and read it back.
Terminal basicsprintfteecat
Lesson 306 of 360
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Terminal basics · 8 minutes
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learner@clairos:/home/learner $
Unix ops lab: type a command, press Enter
Instructions
8 minutes
Click any instruction for the command details, the why, and the common mistake to avoid.
Run cat lab/terminal-ready.txt.
cat lab/terminal-ready.txt
Run wc -l lab/terminal-ready.txt.
wc -l lab/terminal-ready.txt
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Lesson support
What to notice while you play.
Build repeatable confidence with proving where command output was written.
Start with printf terminal-ready | tee lab/terminal-ready.txt, inspect the result, then continue in order.
Proving where command output was written helps operators explain what they know before they change anything.
- Skipping the output that proves proving where command output was written.
- Changing several things before recording a baseline.
Reference
Commands in this lesson.
printf <text>
Print formatted training text.
cat <file>
Print text file contents.
tee <file>
Write piped text to a lab file and keep it on screen.