View source for Linux Basic/Linux Self Assessment

= Linux Basics — Self-Assessment =

This page lets you verify that you have mastered the material from the [[Linux Basics Course]]. Work through the parts in order on '''Anunna'''. The final challenge produces a report file that proves you completed every step — submit (or keep) that file as evidence.

'''Prerequisites:''' an Anunna account and the course data at <code>/lustre/shared/hpcCourses/shell-lesson-data.zip</code>.

'''Rules:'''
* Do everything from the command line. No file-manager GUIs, no OnDemand file browser (the shell is fine).
* If you get stuck, refer back to the [[:File:WUR Linux Basics Course 2026 Feb.pdf|course slides]]  use <code>man</code>, <code>--help</code>, or the [https://swcarpentry.github.io/shell-novice/ Software Carpentry shell course] — that is part of the skill.

== Part 1 — Connect and orient ==

# Connect to Anunna via SSH.
# Confirm where you are with <code>pwd</code>. You should be in your home directory (<code>/home/WUR/yourusername</code>).

== Part 2 — Build the workspace (directories and navigation) ==

# In your home directory, create this directory tree '''with a single command''':
#: <pre>~/linux_test/
#: ├── data/
#: ├── scripts/
#: └── results/</pre>
#: ''Hint: one <code>mkdir</code> flag makes parent directories for you.''
# Change into <code>~/linux_test/data</code> using a '''relative''' path from your home directory.
# Go back to your home directory using only <code>cd</code> shortcuts (no full paths).

== Part 3 — Work with files ==

# Copy the course archive into your home directory and extract it:
#: <syntaxhighlight lang="bash">
cp /lustre/shared/hpcCourses/shell-lesson-data.zip ~/
unzip ~/shell-lesson-data.zip -d ~/
</syntaxhighlight>
# Find the file <code>unicorn.dat</code> inside the extracted data and '''copy''' it to <code>~/linux_test/data/sample.dat</code>.
# Inside <code>~/linux_test/data</code>, create 12 empty files named <code>run_01.log</code> through <code>run_12.log</code> '''with a single command''' (brace ranges).
# Delete '''only''' the even-numbered log files using wildcards/ranges — in as few commands as you can. Check with <code>ls</code> that exactly 6 odd-numbered files remain.

== Part 4 — Pipes, filters, redirects ==

# Count how many lines in <code>sample.dat</code> contain the pattern <code>TACCGGACAA</code>, using <code>grep</code> piped into <code>wc</code>.
# Redirect that number into <code>~/linux_test/results/pattern_count.txt</code> (it should contain a single number, nothing else).

== Part 5 — Environment variables ==

# Create an environment variable holding your full name and '''export''' it:
#: <syntaxhighlight lang="bash">
export REPORT_AUTHOR="Your Name"
</syntaxhighlight>
# Verify it exists with <code>echo $REPORT_AUTHOR</code> and find it in the output of <code>env</code>.
# ''Question to yourself: why is <code>export</code> needed here? You will find out in the final challenge — your script runs as a child process, and only exported variables reach it.''

== Part 6 — Final challenge: the report script ==

Using a command-line text editor (<code>nano</code> is what the course taught, but <code>vim</code> or <code>emacs</code> are equally fine), create the file <code>~/linux_test/scripts/generate_report.sh</code> with exactly this behaviour. Write it yourself — the skeleton below shows the required output labels, you fill in the commands.

The script must:

* start with the correct '''interpreter header''' for bash,
* write all output to <code>~/linux_test/results/report.txt</code> (overwriting any previous report),
* produce one labelled line per check, in this order:

{| class="wikitable"
! Label !! Content !! What it proves
|-
| <code>USER:</code> || output of <code>whoami</code> || you ran it yourself
|-
| <code>DATE:</code> || output of <code>date</code> || when
|-
| <code>AUTHOR:</code> || value of <code>$REPORT_AUTHOR</code> || you understand <code>export</code>
|-
| <code>SHEBANG:</code> || first line of the script itself (<code>head -n 1 "$0"</code>) || interpreter header present
|-
| <code>PERMS:</code> || permission octal of the script itself (<code>stat -c '%a' "$0"</code>) || you made it executable
|-
| <code>LOGFILES:</code> || number of <code>.log</code> files in <code>~/linux_test/data</code> || Part 3 globbing done
|-
| <code>PATTERN:</code> || contents of <code>~/linux_test/results/pattern_count.txt</code> || Part 4 done
|}

A starting skeleton (the first two lines are done for you):

<syntaxhighlight lang="bash">
#!/bin/bash

REPORT=~/linux_test/results/report.txt

echo "USER: $(whoami)" > "$REPORT"
echo "DATE: $(date)" >> "$REPORT"
# ... your turn: AUTHOR, SHEBANG, PERMS, LOGFILES, PATTERN ...
</syntaxhighlight>

''Mind the difference between <code>></code> and <code>>></code> — only the first line should overwrite.''

=== Run it ===

# Make the script executable for yourself with <code>chmod</code>.
# Change into <code>~/linux_test/scripts</code> and run it with a '''relative''' path:
#: <syntaxhighlight lang="bash">
cd ~/linux_test/scripts
./generate_report.sh
</syntaxhighlight>
# Run it once more from your home directory using the '''full''' path. Both must work.
# ''Bonus question: why does plain <code>generate_report.sh</code> (no <code>./</code>) fail? Which environment variable is responsible?''

=== Check yourself ===

Display the report:

<syntaxhighlight lang="bash">
cat ~/linux_test/results/report.txt
</syntaxhighlight>

You pass if '''all''' of the following hold:

* <code>AUTHOR:</code> shows your name (not empty — if it is empty, you forgot <code>export</code>);
* <code>SHEBANG:</code> shows <code>#!/bin/bash</code>;
* <code>PERMS:</code> starts with a <code>7</code> (e.g. <code>744</code>, <code>755</code>) — owner has read, write '''and''' execute;
* <code>LOGFILES:</code> is <code>6</code>;
* <code>PATTERN:</code> is a number greater than <code>0</code>.

If any line is wrong, fix the corresponding part and re-run the script — that is the whole point of scripts.

== For instructors ==

A submitted <code>report.txt</code> is verifiable at a glance, or in bulk:

<syntaxhighlight lang="bash">
grep -E '^(AUTHOR: .+|SHEBANG: #!/bin/bash|PERMS: 7..|LOGFILES: 6|PATTERN: [1-9])' report.txt | wc -l
# Expect: 5
</syntaxhighlight>

Asking students to also submit the script itself catches copy-pasted reports: the <code>SHEBANG:</code> and <code>PERMS:</code> lines must be consistent with the actual file.

[[Category:Courses]]
[[Category:Linux]]