From 42ca69a43f590e5233b541327b3161ab2f69964f Mon Sep 17 00:00:00 2001
From: "Scott C. MacCallum" <scm@sdf.org>
Date: Tue, 16 Jun 2026 10:40:35 -0400
Subject: [PATCH] Adding files

---
 06-linuxplus-quiz-mode.el       | 954 ++++++++++++++++++++++++++++----
 101-systemd-service-quiz.el     |  49 ++
 102-network-tools-lesson.el     | 123 ++++
 103-network-tools-quiz.el       |  52 ++
 30-auth-log-lesson.el           |  56 ++
 31-auth-log-quiz.el             |  16 +
 40-package-management-lesson.el |  55 ++
 41-package-management-quiz.el   |  16 +
 60-file-permissions-lesson.el   |  74 +++
 9 files changed, 1272 insertions(+), 123 deletions(-)
 create mode 100644 101-systemd-service-quiz.el
 create mode 100644 102-network-tools-lesson.el
 create mode 100644 103-network-tools-quiz.el
 create mode 100644 30-auth-log-lesson.el
 create mode 100644 31-auth-log-quiz.el
 create mode 100644 40-package-management-lesson.el
 create mode 100644 41-package-management-quiz.el
 create mode 100644 60-file-permissions-lesson.el

diff --git a/06-linuxplus-quiz-mode.el b/06-linuxplus-quiz-mode.el
index fb82d0b..8c6393b 100644
--- a/06-linuxplus-quiz-mode.el
+++ b/06-linuxplus-quiz-mode.el
@@ -1,156 +1,864 @@
 ;;; 06-linuxplus-quiz-mode.el --- linuxplus-quiz-mode
 
-(defvar-local linuxplus-quiz-questions nil
-  "Questions for the current Linux+ quiz buffer.")
+(defvar-local linuxplus-quiz-lesson-name nil)
+(defvar-local linuxplus-quiz-questions nil)
+(defvar-local linuxplus-quiz-user-answers nil)
+(defvar-local linuxplus-quiz-current-question 0)
+(defvar-local linuxplus-quiz-current-choice 0)
+(defvar-local linuxplus-quiz-return-window-configuration nil)
+(defvar-local linuxplus-quiz-return-buffer nil)
 
-(defvar-local linuxplus-quiz-answers nil
-  "Correct answers for the current Linux+ quiz buffer.")
+(defun linuxplus-quiz--question-type (question)
+  (plist-get question :type))
 
-(defvar-local linuxplus-quiz-user-answers nil
-  "User answers for the current Linux+ quiz buffer.")
+(defun linuxplus-quiz--question-prompt (question)
+  (plist-get question :prompt))
 
-(defvar-local linuxplus-quiz-current-index 0
-  "Current question index in the Linux+ quiz buffer.")
+(defun linuxplus-quiz--question-answer (question)
+  (plist-get question :answer))
 
-(defvar-local linuxplus-quiz-lesson-name nil
-  "Lesson name associated with the current Linux+ quiz buffer.")
+(defun linuxplus-quiz--question-answers (question)
+  (plist-get question :answers))
 
-(defun linuxplus-quiz-answer-marker (answer)
-  "Return a display marker string for ANSWER."
+(defun linuxplus-quiz--question-choices (question)
+  (plist-get question :choices))
+
+(defun linuxplus-quiz--current-question ()
+  (nth linuxplus-quiz-current-question
+       linuxplus-quiz-questions))
+
+(defun linuxplus-quiz--current-user-answer ()
+  (nth linuxplus-quiz-current-question
+       linuxplus-quiz-user-answers))
+
+(defun linuxplus-quiz--set-current-user-answer (answer)
+  (setf
+   (nth linuxplus-quiz-current-question
+        linuxplus-quiz-user-answers)
+   answer))
+
+(defun linuxplus-quiz--answer-marker (answer)
   (cond
-   ((eq answer 'y) "[y]")
-   ((eq answer 'n) "[n]")
-   (t "[ ]")))
+   ((eq answer 'true) "[t]")
+   ((eq answer 'false) "[f]")
+   ((eq answer 'yes) "[y]")
+   ((eq answer 'no) "[n]")
+   ((eq answer 'selected) "[*]")
+   (t "[]")))
 
-(defun linuxplus-quiz-answer-string (answer)
-  "Return a readable string for ANSWER."
+(defun linuxplus-quiz--answer-string (answer)
   (cond
-   ((eq answer 'y) "y")
-   ((eq answer 'n) "n")
-   (t "unanswered")))
+   ((eq answer 'true) "true")
+   ((eq answer 'false) "false")
+   ((eq answer 'yes) "yes")
+   ((eq answer 'no) "no")
+   ((listp answer) (format "%S" answer))
+   ((null answer) "unanswered")
+   (t (format "%S" answer))))
 
-(defun linuxplus-quiz-result-string (user-answer correct-answer)
-  "Return a readable result string comparing USER-ANSWER to CORRECT-ANSWER."
-  (if (eq user-answer correct-answer)
-      "correct"
-    "incorrect"))
+(defun linuxplus-quiz--correct-answer-for-display
+    (question)
+  (let ((type
+         (linuxplus-quiz--question-type question)))
+    (cond
+     ((memq type '(true-false yes-no))
+      (linuxplus-quiz--answer-string
+       (linuxplus-quiz--question-answer question)))
+     ((eq type 'multiple)
+      (format "%S"
+              (linuxplus-quiz--question-answers
+               question)))
+     (t "unknown"))))
+
+(defun linuxplus-quiz--advance-question ()
+  (when (< linuxplus-quiz-current-question
+           (1- (length linuxplus-quiz-questions)))
+    (setq linuxplus-quiz-current-question
+          (1+ linuxplus-quiz-current-question))
+    (setq linuxplus-quiz-current-choice 0)))
+
+(defun linuxplus-quiz--previous-question ()
+  (when (> linuxplus-quiz-current-question 0)
+    (setq linuxplus-quiz-current-question
+          (1- linuxplus-quiz-current-question))
+    (setq linuxplus-quiz-current-choice 0)))
+
+(defun linuxplus-quiz--multiple-selected-p
+    (answer choice-index)
+  (and (listp answer)
+       (memq choice-index answer)))
+
+(defun linuxplus-quiz--advance-choice ()
+  "Advance to next multiple-choice bracket."
+  (let* ((question
+          (linuxplus-quiz--current-question))
+         (choices
+          (linuxplus-quiz--question-choices
+           question)))
+    (when (and choices
+               (< linuxplus-quiz-current-choice
+                  (1- (length choices))))
+      (setq linuxplus-quiz-current-choice
+            (1+ linuxplus-quiz-current-choice)))))
+
+(defun linuxplus-quiz--toggle-current-choice ()
+  "Toggle current multiple-choice selection."
+  (let* ((answer
+          (copy-sequence
+           (or
+            (linuxplus-quiz--current-user-answer)
+            nil)))
+         (choice linuxplus-quiz-current-choice)
+         (was-selected
+          (memq choice answer)))
+
+    (if was-selected
+
+        ;; Remove selection and stay.
+        (setq answer
+              (delq choice answer))
+
+      ;; Add selection and advance.
+      (push choice answer)
+
+      (setq answer
+            (sort answer #'<))
+
+      (linuxplus-quiz--set-current-user-answer
+       answer)
+
+      (linuxplus-quiz--advance-choice)
+
+      ;; Stop removal logic.
+      (setq answer nil))
+
+    ;; Removal path only.
+    (when answer
+      (setq answer
+            (sort answer #'<))
+
+      (linuxplus-quiz--set-current-user-answer
+       answer))))
+
+(defun linuxplus-quiz--answer-correct-p
+    (question user-answer)
+
+  (let ((type
+         (linuxplus-quiz--question-type question)))
+
+    (cond
+
+     ((memq type '(true-false yes-no))
+      (eq user-answer
+          (linuxplus-quiz--question-answer
+           question)))
+
+     ((eq type 'multiple)
+      (equal
+       (sort
+        (copy-sequence
+         (or user-answer nil))
+        #'<)
+
+       (sort
+        (copy-sequence
+         (linuxplus-quiz--question-answers
+          question))
+        #'<)))
+
+     (t nil))))
+
+(defun linuxplus-quiz--question-index-at-point ()
+  "Return zero-based question index at point."
+  (save-excursion
+    (let ((found nil))
+      (when
+          (re-search-backward
+           "^\\([0-9]+\\)\\.$"
+           nil t)
+
+        (setq found
+              (1-
+               (string-to-number
+                (match-string 1)))))
+
+      (when
+          (and found
+               (>= found 0)
+               (< found
+                  (length
+                   linuxplus-quiz-questions)))
+        found))))
+
+(defun linuxplus-quiz--choice-index-at-point ()
+  "Return zero-based multiple-choice bracket index at point."
+
+  (save-excursion
+
+    (let ((current-line
+           (line-beginning-position))
+
+          (question-start nil)
+
+          (choice-index 0)
+
+          result)
+
+      ;; Find question start.
+      (when
+          (re-search-backward
+           "^\\([0-9]+\\)\\.$"
+           nil t)
+
+        (setq question-start (point)))
+
+      (when question-start
+
+        ;; Start searching after question header.
+        (forward-line 1)
+
+        ;; Walk brackets.
+        (while
+            (and
+             (null result)
+             (re-search-forward
+              "\\[[^]]*\\]"
+              nil t))
+
+          ;; Did we hit current line?
+          (when
+              (= (line-beginning-position)
+                 current-line)
+
+            (setq result choice-index))
+
+          ;; Next bracket index.
+          (setq choice-index
+                (1+ choice-index))))
+
+      result)))
+
+(defun linuxplus-quiz--sync-current-position-from-point ()
+  "Update current question and multiple-choice bracket from cursor position."
+
+  (let ((question-index
+         (linuxplus-quiz--question-index-at-point)))
+
+    (when question-index
+
+      (setq linuxplus-quiz-current-question
+            question-index)
+
+      (if
+          (eq
+           (linuxplus-quiz--question-type
+            (linuxplus-quiz--current-question))
+           'multiple)
+
+          (setq linuxplus-quiz-current-choice
+                (or
+                 (linuxplus-quiz--choice-index-at-point)
+                 0))
+
+        (setq linuxplus-quiz-current-choice 0)))))
+
+(defun linuxplus-quiz--invalid-input-message ()
+
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (let ((type
+         (linuxplus-quiz--question-type
+          (linuxplus-quiz--current-question))))
+
+    (cond
+
+     ((eq type 'true-false)
+      (message
+       "Valid input: t for true, f for false."))
+
+     ((eq type 'yes-no)
+      (message
+       "Valid input: y for yes, n for no."))
+
+     ((eq type 'multiple)
+      (message
+       "Use the space bar to add/remove the * character."))
+
+     (t
+      (message "Invalid input.")))))
+
+(defun linuxplus-quiz--set-answer-and-maybe-advance
+    (answer)
+
+  "Set ANSWER.
+If unanswered, advance.
+If replacing, stay."
+
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (let ((old-answer
+         (linuxplus-quiz--current-user-answer)))
+
+    (linuxplus-quiz--set-current-user-answer
+     answer)
+
+    (unless old-answer
+      (linuxplus-quiz--advance-question))
+
+    (linuxplus-quiz-render)))
 
 (defun linuxplus-quiz-render ()
-  "Render the current Linux+ quiz buffer."
+
   (let ((inhibit-read-only t))
+
     (erase-buffer)
+
     (insert "Linux+ Quiz\n")
     (insert "===========\n\n")
-    (insert "y = yes, n = no, b = back, f = forward, x = finish, q = quit\n\n")
-    (dotimes (i (length linuxplus-quiz-questions))
-      (let ((prefix (if (= i linuxplus-quiz-current-index) ">" " "))
-            (marker (linuxplus-quiz-answer-marker
-                     (nth i linuxplus-quiz-user-answers)))
-            (question (nth i linuxplus-quiz-questions)))
-        (insert (format "%s %s %d. %s\n"
-                        prefix marker (1+ i) question)))))
-  (goto-char (point-min)))
 
-(defun linuxplus-quiz-finish ()
-  "Finish the current quiz, record the score, and show detailed results."
-  (interactive)
-  (let ((score 0)
-        (total (length linuxplus-quiz-questions)))
-    (dotimes (i total)
-      (when (eq (nth i linuxplus-quiz-user-answers)
-                (nth i linuxplus-quiz-answers))
-        (setq score (1+ score))))
-    (linuxplus-record-score linuxplus-quiz-lesson-name score)
-    (let ((inhibit-read-only t))
-      (erase-buffer)
-      (insert "Linux+ Quiz Results\n")
-      (insert "===================\n\n")
-      (insert (format "Lesson: %s\n" linuxplus-quiz-lesson-name))
-      (insert (format "Score: %d/%d\n\n" score total))
-      (insert "Detailed review:\n\n")
-      (dotimes (i total)
-        (let ((question (nth i linuxplus-quiz-questions))
-              (user-answer (nth i linuxplus-quiz-user-answers))
-              (correct-answer (nth i linuxplus-quiz-answers)))
-          (insert (format "%d. %s\n" (1+ i) question))
-          (insert (format "   Your answer:    %s\n"
-                          (linuxplus-quiz-answer-string user-answer)))
-          (insert (format "   Correct answer: %s\n"
-                          (linuxplus-quiz-answer-string correct-answer)))
-          (insert (format "   Result:         %s\n\n"
-                          (linuxplus-quiz-result-string
-                           user-answer correct-answer))))))
-    (goto-char (point-min))
-    (view-mode 1)
-    (message "Quiz complete. Score: %d/%d" score total)))
+    (let ((current-type
+           (linuxplus-quiz--question-type
+            (linuxplus-quiz--current-question))))
 
-(defun linuxplus-quiz-answer-y ()
-  "Answer yes to the current Linux+ quiz question."
-  (interactive)
-  (setf (nth linuxplus-quiz-current-index linuxplus-quiz-user-answers) 'y)
-  (if (< linuxplus-quiz-current-index
-         (1- (length linuxplus-quiz-questions)))
-      (setq linuxplus-quiz-current-index
-            (1+ linuxplus-quiz-current-index))
-    (linuxplus-quiz-render))
-  (when (derived-mode-p 'linuxplus-quiz-mode)
-    (linuxplus-quiz-render)))
+      (cond
+
+       ((eq current-type 'true-false)
+        (insert
+         "Type 't' for true or 'f' for false inside the brackets.\n"))
+
+       ((eq current-type 'yes-no)
+        (insert
+         "Type 'y' for yes or 'n' for no inside the brackets.\n"))
+
+       ((eq current-type 'multiple)
+        (insert
+         "Use the space bar to add/remove the * character for multiple choice questions.\n"))
+
+       (t
+        (insert "Answer the question.\n"))))
+
+    (insert
+     "b = back, TAB = forward, x = finish, q = quit\n\n")
+
+    (dotimes
+        (i (length linuxplus-quiz-questions))
+
+      (let* ((question
+              (nth i linuxplus-quiz-questions))
+
+             (type
+              (linuxplus-quiz--question-type
+               question))
+
+             (prompt
+              (linuxplus-quiz--question-prompt
+               question))
+
+             (user-answer
+              (nth i linuxplus-quiz-user-answers))
+
+             (current-question-p
+              (= i
+                 linuxplus-quiz-current-question)))
+
+        (insert
+         (format "%d.\n" (1+ i)))
+
+        (insert
+         (format "    %s\n" prompt))
+
+        (cond
+
+         ((eq type 'true-false)
+
+          (insert
+           (format
+            "%s    %s True or False\n\n"
+
+            (if current-question-p
+                ">"
+              " ")
+
+            (linuxplus-quiz--answer-marker
+             user-answer))))
+
+         ((eq type 'yes-no)
+
+          (insert
+           (format
+            "%s    %s Yes or No\n\n"
+
+            (if current-question-p
+                ">"
+              " ")
+
+            (linuxplus-quiz--answer-marker
+             user-answer))))
+
+         ((eq type 'multiple)
+
+          (let ((choices
+                 (linuxplus-quiz--question-choices
+                  question)))
+
+            (dotimes
+                (choice-index
+                 (length choices))
+
+              (let*
+                  ((selected
+                    (if
+                        (linuxplus-quiz--multiple-selected-p
+                         user-answer
+                         choice-index)
+                        'selected
+                      nil))
+
+                   (choice-current-p
+                    (and
+                     current-question-p
+                     (= choice-index
+                        linuxplus-quiz-current-choice))))
+
+                (insert
+                 (format
+                  "%s    %s %s\n"
+
+                  (if choice-current-p
+                      ">"
+                    " ")
+
+                  (linuxplus-quiz--answer-marker
+                   selected)
+
+                  (nth choice-index
+                       choices))))))
+
+          (insert "\n")))))
+
+    (insert
+     "\nReminder: x = finish quiz, q = quit/return to lesson.\n"))
+
+  (linuxplus-quiz-goto-current-answer))
+
+(defun linuxplus-quiz-goto-current-answer ()
+
+  (goto-char (point-min))
+
+  (let ((target-question
+         (format "^%d\\.$"
+                 (1+
+                  linuxplus-quiz-current-question))))
+
+    (when
+        (re-search-forward
+         target-question
+         nil t)
+
+      (let ((type
+             (linuxplus-quiz--question-type
+              (linuxplus-quiz--current-question))))
+
+        (cond
+
+         ((memq type '(true-false yes-no))
+
+          (when
+              (re-search-forward
+               "\\[[^]]*\\]"
+               nil t)
+
+            (backward-char 1)))
+
+         ((eq type 'multiple)
+
+          (dotimes
+              (_ linuxplus-quiz-current-choice)
+
+            (re-search-forward
+             "\\[[^]]*\\]"
+             nil t))
+
+          (when
+              (re-search-forward
+               "\\[[^]]*\\]"
+               nil t)
+
+            (backward-char 1))))))))
+
+(defun linuxplus-quiz-answer-true ()
 
-(defun linuxplus-quiz-answer-n ()
-  "Answer no to the current Linux+ quiz question."
   (interactive)
-  (setf (nth linuxplus-quiz-current-index linuxplus-quiz-user-answers) 'n)
-  (if (< linuxplus-quiz-current-index
-         (1- (length linuxplus-quiz-questions)))
-      (setq linuxplus-quiz-current-index
-            (1+ linuxplus-quiz-current-index))
-    (linuxplus-quiz-render))
-  (when (derived-mode-p 'linuxplus-quiz-mode)
-    (linuxplus-quiz-render)))
+
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (if
+      (eq
+       (linuxplus-quiz--question-type
+        (linuxplus-quiz--current-question))
+       'true-false)
+
+      (linuxplus-quiz--set-answer-and-maybe-advance
+       'true)
+
+    (linuxplus-quiz--invalid-input-message)))
+
+(defun linuxplus-quiz-answer-false ()
+
+  (interactive)
+
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (if
+      (eq
+       (linuxplus-quiz--question-type
+        (linuxplus-quiz--current-question))
+       'true-false)
+
+      (linuxplus-quiz--set-answer-and-maybe-advance
+       'false)
+
+    (linuxplus-quiz--invalid-input-message)))
+
+(defun linuxplus-quiz-answer-yes ()
+
+  (interactive)
+
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (if
+      (eq
+       (linuxplus-quiz--question-type
+        (linuxplus-quiz--current-question))
+       'yes-no)
+
+      (linuxplus-quiz--set-answer-and-maybe-advance
+       'yes)
+
+    (linuxplus-quiz--invalid-input-message)))
+
+(defun linuxplus-quiz-answer-no ()
+
+  (interactive)
+
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (if
+      (eq
+       (linuxplus-quiz--question-type
+        (linuxplus-quiz--current-question))
+       'yes-no)
+
+      (linuxplus-quiz--set-answer-and-maybe-advance
+       'no)
+
+    (linuxplus-quiz--invalid-input-message)))
+
+(defun linuxplus-quiz-toggle-multiple ()
+
+  (interactive)
+
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (if
+      (eq
+       (linuxplus-quiz--question-type
+        (linuxplus-quiz--current-question))
+       'multiple)
+
+      (progn
+        (linuxplus-quiz--toggle-current-choice)
+        (linuxplus-quiz-render))
+
+    (linuxplus-quiz--invalid-input-message)))
 
 (defun linuxplus-quiz-next ()
-  "Move to next question without changing answer."
+
   (interactive)
-  (when (< linuxplus-quiz-current-index
-           (1- (length linuxplus-quiz-questions)))
-    (setq linuxplus-quiz-current-index
-          (1+ linuxplus-quiz-current-index))
-    (linuxplus-quiz-render)))
+
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (let ((type
+         (linuxplus-quiz--question-type
+          (linuxplus-quiz--current-question))))
+
+    (if
+        (and
+         (eq type 'multiple)
+
+         (< linuxplus-quiz-current-choice
+            (1-
+             (length
+              (linuxplus-quiz--question-choices
+               (linuxplus-quiz--current-question))))))
+
+        (setq linuxplus-quiz-current-choice
+              (1+
+               linuxplus-quiz-current-choice))
+
+      (linuxplus-quiz--advance-question)))
+
+  (linuxplus-quiz-render))
 
 (defun linuxplus-quiz-prev ()
-  "Move to previous question."
+
   (interactive)
-  (when (> linuxplus-quiz-current-index 0)
-    (setq linuxplus-quiz-current-index
-          (1- linuxplus-quiz-current-index))
-    (linuxplus-quiz-render)))
 
-(defvar linuxplus-quiz-mode-map
-  (let ((map (make-sparse-keymap)))
-    (define-key map (kbd "y") #'linuxplus-quiz-answer-y)
-    (define-key map (kbd "n") #'linuxplus-quiz-answer-n)
-    (define-key map (kbd "f") #'linuxplus-quiz-next)
-    (define-key map (kbd "b") #'linuxplus-quiz-prev)
-    (define-key map (kbd "x") #'linuxplus-quiz-finish)
-    (define-key map (kbd "q") #'quit-window)
-    map)
-  "Keymap for `linuxplus-quiz-mode`.")
+  (linuxplus-quiz--sync-current-position-from-point)
+
+  (let ((type
+         (linuxplus-quiz--question-type
+          (linuxplus-quiz--current-question))))
+
+    (if
+        (and
+         (eq type 'multiple)
+         (> linuxplus-quiz-current-choice 0))
+
+        (setq linuxplus-quiz-current-choice
+              (1-
+               linuxplus-quiz-current-choice))
+
+      (linuxplus-quiz--previous-question)))
+
+  (linuxplus-quiz-render))
+
+(defun linuxplus-quiz-invalid-key ()
+  (interactive)
+  (linuxplus-quiz--invalid-input-message))
+
+(defun linuxplus-quiz-return-to-lesson ()
+
+  "Return to lesson/window layout."
+
+  (interactive)
+
+  (let ((config
+         linuxplus-quiz-return-window-configuration)
+
+        (buffer
+         linuxplus-quiz-return-buffer))
+
+    (when
+        (window-configuration-p config)
+
+      (set-window-configuration config))
+
+    (when
+        (buffer-live-p buffer)
+
+      (switch-to-buffer buffer))))
+
+(defun linuxplus-quiz-finish ()
+
+  (interactive)
+
+  (let ((score 0)
+
+        (total
+         (length linuxplus-quiz-questions)))
+
+    (dotimes (i total)
+
+      (when
+          (linuxplus-quiz--answer-correct-p
+           (nth i linuxplus-quiz-questions)
+           (nth i linuxplus-quiz-user-answers))
+
+        (setq score (1+ score))))
+
+    (linuxplus-record-score
+     linuxplus-quiz-lesson-name
+     score)
+
+    (let ((inhibit-read-only t))
+
+      (erase-buffer)
+
+      (insert "Linux+ Quiz Results\n")
+      (insert "===================\n\n")
+
+      (insert
+       (format
+        "Lesson: %s\n"
+        linuxplus-quiz-lesson-name))
+
+      (insert
+       (format
+        "Score: %d/%d\n\n"
+        score total))
+
+      (insert "Detailed review:\n\n")
+
+      (dotimes (i total)
+
+        (let*
+            ((question
+              (nth i linuxplus-quiz-questions))
+
+             (prompt
+              (linuxplus-quiz--question-prompt
+               question))
+
+             (user-answer
+              (nth i linuxplus-quiz-user-answers)))
+
+          (insert
+           (format
+            "%d. %s\n"
+            (1+ i)
+            prompt))
+
+          (insert
+           (format
+            "   Your answer:    %s\n"
+            (linuxplus-quiz--answer-string
+             user-answer)))
+
+          (insert
+           (format
+            "   Correct answer: %s\n"
+            (linuxplus-quiz--correct-answer-for-display
+             question)))
+
+          (insert
+           (format
+            "   Result:         %s\n\n"
+
+            (if
+                (linuxplus-quiz--answer-correct-p
+                 question
+                 user-answer)
+
+                "correct"
+
+              "incorrect")))))
+
+      (insert
+       "Press q to return to the lesson.\n"))
+
+    (goto-char (point-min))
+
+    (linuxplus-quiz-mode)
+
+    (message
+     "Quiz complete. Score: %d/%d"
+     score total)))
+
+(setq linuxplus-quiz-mode-map
+
+      (let ((map
+             (make-sparse-keymap)))
+
+        ;; invalid printable input
+
+        (dotimes (i 95)
+
+          (define-key
+            map
+            (char-to-string (+ i 32))
+            #'linuxplus-quiz-invalid-key))
+
+        ;; valid answers
+
+        (define-key
+          map
+          (kbd "t")
+          #'linuxplus-quiz-answer-true)
+
+        (define-key
+          map
+          (kbd "f")
+          #'linuxplus-quiz-answer-false)
+
+        (define-key
+          map
+          (kbd "y")
+          #'linuxplus-quiz-answer-yes)
+
+        (define-key
+          map
+          (kbd "n")
+          #'linuxplus-quiz-answer-no)
+
+        (define-key
+          map
+          (kbd "SPC")
+          #'linuxplus-quiz-toggle-multiple)
+
+        ;; navigation
+
+        (define-key
+          map
+          (kbd "b")
+          #'linuxplus-quiz-prev)
+
+        (define-key
+          map
+          (kbd "TAB")
+          #'linuxplus-quiz-next)
+
+        (define-key
+          map
+          (kbd "x")
+          #'linuxplus-quiz-finish)
+
+        (define-key
+          map
+          (kbd "q")
+          #'linuxplus-quiz-return-to-lesson)
+
+        map))
+
+(define-derived-mode
+  linuxplus-quiz-mode
+  special-mode
+  "LinuxPlus-Quiz"
+  "Major mode for Linux+ quizzes."
 
-(define-derived-mode linuxplus-quiz-mode special-mode "LinuxPlus-Quiz"
-  "Major mode for Linux+ quiz buffers."
   (setq buffer-read-only t))
 
-(defun linuxplus-start-quiz (lesson questions answers buffer)
-  "Start a Linux+ quiz for LESSON using QUESTIONS and ANSWERS in BUFFER."
-  (let ((buf (get-buffer-create buffer)))
-    (with-current-buffer buf
-      (linuxplus-quiz-mode)
-      (setq linuxplus-quiz-lesson-name lesson)
-      (setq linuxplus-quiz-questions questions)
-      (setq linuxplus-quiz-answers answers)
-      (setq linuxplus-quiz-user-answers (make-list (length questions) nil))
-      (setq linuxplus-quiz-current-index 0)
-      (linuxplus-quiz-render))
-    (pop-to-buffer buf)))
+(defun linuxplus-start-quiz
+    (lesson questions buffer)
+
+  "Start Linux+ quiz in full window."
+
+  (let ((return-config
+         (current-window-configuration))
+
+        (return-buffer
+         (current-buffer))
+
+        (buf
+         (get-buffer-create buffer)))
+
+    (delete-other-windows)
+
+    (switch-to-buffer buf)
+
+    (linuxplus-quiz-mode)
+
+    (setq linuxplus-quiz-return-window-configuration
+          return-config)
+
+    (setq linuxplus-quiz-return-buffer
+          return-buffer)
+
+    (setq linuxplus-quiz-lesson-name
+          lesson)
+
+    (setq linuxplus-quiz-questions
+          questions)
+
+    (setq linuxplus-quiz-user-answers
+          (make-list
+           (length questions)
+           nil))
+
+    (setq linuxplus-quiz-current-question 0)
+
+    (setq linuxplus-quiz-current-choice 0)
+
+    (linuxplus-quiz-render)))
 
 ;;; 06-linuxplus-quiz-mode.el ends here
diff --git a/101-systemd-service-quiz.el b/101-systemd-service-quiz.el
new file mode 100644
index 0000000..dd74fe0
--- /dev/null
+++ b/101-systemd-service-quiz.el
@@ -0,0 +1,49 @@
+;;; 101-systemd-service-quiz.el --- systemd-service-quiz
+
+(defun systemd-service-quiz ()
+  "Quiz for systemd service management."
+  (interactive)
+  (linuxplus-start-quiz
+   'systemd-service-lesson
+   '((:type true-false
+      :prompt "`systemctl start ssh` starts the service immediately but does not enable it at boot."
+      :answer true)
+
+     (:type true-false
+      :prompt "`systemctl enable ssh` starts the service immediately and enables it at boot."
+      :answer false)
+
+     (:type true-false
+      :prompt "`systemctl disable ssh` prevents startup at boot but does not necessarily stop a currently running service."
+      :answer true)
+
+     (:type true-false
+      :prompt "`systemctl mask ssh` is stronger than `systemctl disable ssh` because it prevents normal starting."
+      :answer true)
+
+     (:type true-false
+      :prompt "`systemctl reload ssh` and `systemctl restart ssh` always do exactly the same thing."
+      :answer false)
+
+     (:type true-false
+      :prompt "`systemctl status <service>` is useful when troubleshooting a failed service."
+      :answer true)
+
+     (:type true-false
+      :prompt "`journalctl -u <service>` can show logs for a specific systemd service."
+      :answer true)
+
+     (:type true-false
+      :prompt "`systemctl --failed` can help identify failed units."
+      :answer true)
+
+     (:type yes-no
+      :prompt "On many Red Hat-family systems, is the SSH service commonly named `sshd`?"
+      :answer yes)
+
+     (:type yes-no
+      :prompt "On many Debian-family systems, is the SSH service commonly named `sshd` instead of `ssh`?"
+      :answer no))
+   "*systemd Service Quiz*"))
+
+;;; 101-systemd-service-quiz.el ends here
diff --git a/102-network-tools-lesson.el b/102-network-tools-lesson.el
new file mode 100644
index 0000000..8bddfa9
--- /dev/null
+++ b/102-network-tools-lesson.el
@@ -0,0 +1,123 @@
+;;; 102-network-tools-lesson.el --- network-tools-lesson
+
+(defun network-tools-lesson ()
+  "Linux+ lesson for network troubleshooting tools."
+  (interactive)
+
+  (delete-other-windows)
+
+  (let ((buf (get-buffer-create "*Network Tools Lesson*"))
+        (shell (or shell-file-name
+                   (getenv "SHELL")
+                   "/bin/sh")))
+
+    (switch-to-buffer buf)
+
+    (read-only-mode -1)
+    (erase-buffer)
+
+    (insert
+     "Linux+ Lesson: Network Troubleshooting Tools\n"
+     "============================================\n\n"
+
+     "Concept:\n"
+     "Linux administrators must diagnose network problems quickly.\n"
+     "CompTIA Linux+ expects familiarity with modern networking tools,\n"
+     "basic connectivity testing, interface inspection, DNS testing,\n"
+     "and socket/process inspection.\n\n"
+
+     "Core commands:\n\n"
+
+     "ip addr\n"
+     "    Display IP address information.\n\n"
+
+     "ip route\n"
+     "    Display routing table.\n\n"
+
+     "ping\n"
+     "    Test ICMP connectivity.\n\n"
+
+     "ss -tulpn\n"
+     "    Show listening TCP/UDP sockets and associated processes.\n\n"
+
+     "hostnamectl\n"
+     "    Show or change persistent hostname.\n\n"
+
+     "dig\n"
+     "    Query DNS servers.\n\n"
+
+     "traceroute\n"
+     "    Show network path hops.\n\n"
+
+     "curl\n"
+     "    Retrieve data from URLs and test HTTP services.\n\n"
+
+     "wget\n"
+     "    Download files from remote systems.\n\n"
+
+     "nmap\n"
+     "    Network discovery and port scanning.\n\n"
+
+     "Hands-on tasks:\n\n"
+
+     "1. Display IP addresses:\n"
+     "   ip addr\n\n"
+
+     "2. Display routes:\n"
+     "   ip route\n\n"
+
+     "3. Test connectivity:\n"
+     "   ping -c 4 google.com\n\n"
+
+     "4. Inspect listening services:\n"
+     "   ss -tulpn\n\n"
+
+     "5. Query DNS:\n"
+     "   dig google.com\n\n"
+
+     "6. Download a webpage:\n"
+     "   curl https://example.com\n\n"
+
+     "7. Download a file:\n"
+     "   wget https://example.com/index.html\n\n"
+
+     "8. Display hostname:\n"
+     "   hostnamectl\n\n"
+
+     "9. Run a localhost scan:\n"
+     "   sudo nmap localhost\n\n"
+
+     "Important Linux+ exam traps:\n\n"
+
+     "- `ip` replaces many older networking tools.\n"
+     "- `ss` is preferred over `netstat` on modern systems.\n"
+     "- `dig` is for DNS lookups.\n"
+     "- `ping` uses ICMP.\n"
+     "- `curl` is commonly used for API and HTTP testing.\n"
+     "- `wget` is commonly used for recursive or file downloads.\n"
+     "- `nmap` is heavily associated with network discovery and auditing.\n"
+     "- `hostnamectl` changes persistent hostnames.\n\n"
+
+     "Debian/Rocky notes:\n\n"
+
+     "- `dig` may require package installation.\n"
+     "- Debian package: dnsutils\n"
+     "- Rocky package: bind-utils\n\n"
+
+     "When finished, run:\n\n"
+     "M-x network-tools-quiz\n")
+
+    (goto-char (point-min))
+    (view-mode 1)
+
+    (split-window-below)
+    (other-window 1)
+
+    (let ((term (get-buffer "*term*")))
+      (if (buffer-live-p term)
+          (switch-to-buffer term)
+        (ansi-term shell "term")))
+
+    (other-window -1)))
+
+;;; 102-network-tools-lesson.el ends here
diff --git a/103-network-tools-quiz.el b/103-network-tools-quiz.el
new file mode 100644
index 0000000..cbd34b5
--- /dev/null
+++ b/103-network-tools-quiz.el
@@ -0,0 +1,52 @@
+;;; 103-network-tools-quiz.el --- network-tools-quiz
+
+(defun network-tools-quiz ()
+  "Quiz for Linux network troubleshooting tools."
+  (interactive)
+
+  (linuxplus-start-quiz
+   'network-tools-lesson
+
+   '((:type true-false
+      :prompt "`ss -tulpn` can display listening sockets and processes."
+      :answer true)
+
+     (:type true-false
+      :prompt "`dig` is commonly used for DNS lookups."
+      :answer true)
+
+     (:type true-false
+      :prompt "`ping` primarily tests DNS zone transfers."
+      :answer false)
+
+     (:type true-false
+      :prompt "`ip addr` displays interface addressing information."
+      :answer true)
+
+     (:type true-false
+      :prompt "`hostnamectl` can manage persistent hostnames."
+      :answer true)
+
+     (:type true-false
+      :prompt "`wget` is primarily associated with downloading remote files."
+      :answer true)
+
+     (:type true-false
+      :prompt "`curl` is commonly used for HTTP/API testing."
+      :answer true)
+
+     (:type true-false
+      :prompt "`netstat` is generally preferred over `ss` on modern Linux systems."
+      :answer false)
+
+     (:type yes-no
+      :prompt "Does `ping` use ICMP packets?"
+      :answer yes)
+
+     (:type yes-no
+      :prompt "On Debian-family systems, is the `dig` command commonly provided by the `dnsutils` package?"
+      :answer yes))
+
+   "*Network Tools Quiz*"))
+
+;;; 103-network-tools-quiz.el ends here
diff --git a/30-auth-log-lesson.el b/30-auth-log-lesson.el
new file mode 100644
index 0000000..c95f4d5
--- /dev/null
+++ b/30-auth-log-lesson.el
@@ -0,0 +1,56 @@
+;;; 30-auth-log-lesson.el --- auth-log-lesson
+
+(defun auth-log-lesson ()
+  "Linux+ lesson for authentication logs."
+  (interactive)
+  (delete-other-windows)
+  (let ((buf (get-buffer-create "*Auth Log Lesson*"))
+        (shell (or shell-file-name (getenv "SHELL") "/bin/sh")))
+    (switch-to-buffer buf)
+    (read-only-mode -1)
+    (erase-buffer)
+    (insert
+     "Linux+ Lesson: Authentication Logs\n"
+     "=================================\n\n"
+     "Concept:\n"
+     "Different Linux distributions store authentication logs in different locations.\n\n"
+     "You MUST know this for Linux+:\n\n"
+     "  Red Hat / RHEL / Rocky / Alma:\n"
+     "    /var/log/secure\n\n"
+     "  Debian / Ubuntu:\n"
+     "    /var/log/auth.log\n\n"
+     "Hands-on tasks (run in the terminal below):\n\n"
+     "1. Try viewing both files:\n"
+     "     sudo less /var/log/auth.log\n"
+     "     sudo less /var/log/secure\n\n"
+     "   One of these will exist, depending on your distro.\n\n"
+     "2. Search for failed logins:\n"
+     "     sudo grep -i fail /var/log/auth.log\n"
+     "     sudo grep -i fail /var/log/secure\n\n"
+     "3. Search for ssh login activity:\n"
+     "     sudo grep ssh /var/log/auth.log\n"
+     "     sudo grep ssh /var/log/secure\n\n"
+     "4. Count failed login attempts:\n"
+     "     sudo grep -i fail <file> | wc -l\n\n"
+     "Replace <file> with the correct log file for your system.\n\n"
+     "What to notice:\n"
+     "- Which file exists\n"
+     "- What failed login entries look like\n"
+     "- How grep helps filter logs\n\n"
+     "Linux+ exam trap:\n"
+     "If the question mentions failed login attempts on a Red Hat system,\n"
+     "the answer is:\n\n"
+     "  /var/log/secure\n\n"
+     "When finished, run:\n"
+     "  M-x auth-log-quiz\n")
+    (goto-char (point-min))
+    (view-mode 1)
+    (split-window-below)
+    (other-window 1)
+    (let ((term (get-buffer "*term*")))
+      (if (buffer-live-p term)
+          (switch-to-buffer term)
+        (ansi-term shell "term")))
+    (other-window -1)))
+
+;;; 30-auth-log-lesson.el ends here
diff --git a/31-auth-log-quiz.el b/31-auth-log-quiz.el
new file mode 100644
index 0000000..e4207c3
--- /dev/null
+++ b/31-auth-log-quiz.el
@@ -0,0 +1,16 @@
+;;; 31-auth-log-quiz.el --- auth-log-quiz
+
+(defun auth-log-quiz ()
+  "Quiz for authentication log knowledge."
+  (interactive)
+  (linuxplus-start-quiz
+   'auth-log-lesson
+   '("Is /var/log/secure used on Red Hat systems?"
+     "Is /var/log/auth.log used on Debian-based systems?"
+     "Does grep help filter log entries?"
+     "Is /var/log/messages used for authentication logs?"
+     "Can failed logins be found using grep fail?")
+   '(y y y n y)
+   "*Auth Log Quiz*"))
+
+;;; 31-auth-log-quiz.el ends here
diff --git a/40-package-management-lesson.el b/40-package-management-lesson.el
new file mode 100644
index 0000000..a51ebd5
--- /dev/null
+++ b/40-package-management-lesson.el
@@ -0,0 +1,55 @@
+;;; 40-package-management-lesson.el --- package-management-lesson
+
+(defun package-management-lesson ()
+  "Linux+ lesson for apt vs dnf package management."
+  (interactive)
+  (delete-other-windows)
+  (let ((buf (get-buffer-create "*Package Management Lesson*"))
+        (shell (or shell-file-name (getenv "SHELL") "/bin/sh")))
+    (switch-to-buffer buf)
+    (read-only-mode -1)
+    (erase-buffer)
+    (insert
+     "Linux+ Lesson: Package Management (Debian vs Red Hat)\n"
+     "=====================================================\n\n"
+     "You MUST know both ecosystems.\n\n"
+     "Debian-based systems (Debian, Ubuntu):\n"
+     "  apt update        → refresh package list\n"
+     "  apt upgrade       → upgrade installed packages\n"
+     "  apt install pkg   → install package\n"
+     "  apt remove pkg    → remove package\n\n"
+     "Red Hat-based systems (RHEL, Rocky, Alma):\n"
+     "  dnf check-update  → check for updates\n"
+     "  dnf upgrade       → upgrade system\n"
+     "  dnf install pkg   → install package\n"
+     "  dnf remove pkg    → remove package\n\n"
+     "Hands-on tasks:\n\n"
+     "DEBIAN VM:\n"
+     "  sudo apt update\n"
+     "  sudo apt install tree\n"
+     "  tree\n"
+     "  sudo apt remove tree\n\n"
+     "ROCKY VM:\n"
+     "  sudo dnf check-update\n"
+     "  sudo dnf install tree\n"
+     "  tree\n"
+     "  sudo dnf remove tree\n\n"
+     "What to notice:\n"
+     "- Command differences (apt vs dnf)\n"
+     "- Same concepts, different syntax\n\n"
+     "Linux+ exam traps:\n"
+     "- apt is NOT used on Red Hat\n"
+     "- dnf/yum are NOT used on Debian\n\n"
+     "When finished, run:\n"
+     "  M-x package-management-quiz\n")
+    (goto-char (point-min))
+    (view-mode 1)
+    (split-window-below)
+    (other-window 1)
+    (let ((term (get-buffer "*term*")))
+      (if (buffer-live-p term)
+          (switch-to-buffer term)
+        (ansi-term shell "term")))
+    (other-window -1)))
+
+;;; 40-package-management-lesson.el ends here
diff --git a/41-package-management-quiz.el b/41-package-management-quiz.el
new file mode 100644
index 0000000..ea2eb29
--- /dev/null
+++ b/41-package-management-quiz.el
@@ -0,0 +1,16 @@
+;;; 41-package-management-quiz.el --- package-management-quiz
+
+(defun package-management-quiz ()
+  "Quiz for apt vs dnf knowledge."
+  (interactive)
+  (linuxplus-start-quiz
+   'package-management-lesson
+   '("Is apt used on Debian-based systems?"
+     "Is dnf used on Red Hat-based systems?"
+     "Does apt update refresh package lists?"
+     "Does dnf install install packages?"
+     "Can apt be used on Rocky Linux?")
+   '(y y y y n)
+   "*Package Management Quiz*"))
+
+;;; 41-package-management-quiz.el ends here
diff --git a/60-file-permissions-lesson.el b/60-file-permissions-lesson.el
new file mode 100644
index 0000000..353e737
--- /dev/null
+++ b/60-file-permissions-lesson.el
@@ -0,0 +1,74 @@
+;;; 60-file-permissions-lesson.el --- file-permissions-lesson
+
+(defun file-permissions-lesson ()
+  "Linux+ lesson for file permissions and ownership."
+  (interactive)
+  (delete-other-windows)
+  (let ((buf (get-buffer-create "*File Permissions Lesson*"))
+        (shell (or shell-file-name (getenv "SHELL") "/bin/sh")))
+    (switch-to-buffer buf)
+    (read-only-mode -1)
+    (erase-buffer)
+    (insert
+     "Linux+ Lesson: File Permissions and Ownership\n"
+     "============================================\n\n"
+     "Concepts:\n"
+     "- chmod changes permissions\n"
+     "- chown changes ownership\n"
+     "- rwx permissions apply to:\n"
+     "    user / group / others\n\n"
+     "Permission values:\n"
+     "  r = 4\n"
+     "  w = 2\n"
+     "  x = 1\n\n"
+     "Common octal permissions:\n"
+     "  644 = rw-r--r--\n"
+     "  755 = rwxr-xr-x\n"
+     "  600 = rw-------\n"
+     "  700 = rwx------\n\n"
+     "Hands-on tasks:\n\n"
+     "1. Create a practice directory:\n"
+     "     mkdir ~/linuxplus-permissions\n\n"
+     "2. Enter it:\n"
+     "     cd ~/linuxplus-permissions\n\n"
+     "3. Create a file:\n"
+     "     touch testfile\n\n"
+     "4. View permissions:\n"
+     "     ls -l\n\n"
+     "5. Change permissions to 644:\n"
+     "     chmod 644 testfile\n"
+     "     ls -l\n\n"
+     "6. Change permissions to 755:\n"
+     "     chmod 755 testfile\n"
+     "     ls -l\n\n"
+     "7. Use symbolic mode:\n"
+     "     chmod u+x testfile\n"
+     "     chmod g-w testfile\n"
+     "     ls -l\n\n"
+     "8. View ownership:\n"
+     "     ls -l\n\n"
+     "9. Change ownership (requires sudo):\n"
+     "     sudo chown root:root testfile\n"
+     "     ls -l\n\n"
+     "10. Return ownership to yourself:\n"
+     "     sudo chown $USER:$USER testfile\n"
+     "     ls -l\n\n"
+     "Linux+ exam traps:\n"
+     "- chmod changes permissions, NOT ownership\n"
+     "- chown changes ownership\n"
+     "- x on directories means traversal\n"
+     "- 755 is common for executable files/directories\n"
+     "- 644 is common for regular files\n\n"
+     "When finished, run:\n"
+     "  M-x file-permissions-quiz\n")
+    (goto-char (point-min))
+    (view-mode 1)
+    (split-window-below)
+    (other-window 1)
+    (let ((term (get-buffer "*term*")))
+      (if (buffer-live-p term)
+          (switch-to-buffer term)
+        (ansi-term shell "term")))
+    (other-window -1)))
+
+;;; 60-file-permissions-lesson.el ends here