routine update, no changes

qfetchC-notes.txt

@@ -1,28 +1,15 @@
-Perfect — let’s switch hats from *“just making it work”* to *“learning C properly”*.
-I’ll explain **how to read and think about this file**, not just what it does.
-
-I’ll reference the structure you now have in the file and explain the *C concepts* behind each part.
-
----
-
-## 1️⃣ The mindset shift: C vs C++
+## The mindset shift: C vs C++
 
 In C:
 
-* ❌ No classes, no RAII, no `std::string`
-* ✅ **You control memory explicitly**
-* ✅ Functions are small, focused, and composable
-* ✅ Portability comes from *conditional compilation*
+ - ❌ No classes, no RAII, no `std::string`
+ - ✅ **You control memory explicitly**
+ - ✅ Functions are small, focused, and composable
+ - ✅ Portability comes from *conditional compilation*
 
-Your program follows a **very idiomatic C pattern**:
+ - “Each function returns ownership of dynamically allocated data, and the caller frees it.”*
 
-> *“Each function returns ownership of dynamically allocated data, and the caller frees it.”*
-
-That’s a **huge** C concept to internalize.
-
----
-
-## 2️⃣ Feature macros (`_POSIX_C_SOURCE`)
+## Feature macros (`_POSIX_C_SOURCE`)
 
 ```c
 #define _POSIX_C_SOURCE 200809L
@@ -32,21 +19,14 @@ That’s a **huge** C concept to internalize.
 
 C standard libraries hide some functions unless you *opt in*.
 
-This line tells the compiler:
-
-> “I want modern POSIX features like `strdup`, `gethostname`, `sysconf`.”
-
 Without it:
 
 * Some systems won’t expose those functions
 * You’ll get mysterious warnings or missing symbols
 
-**Lesson:**
-👉 In C, *what functions exist* depends on feature macros.
-
 ---
 
-## 3️⃣ Headers: what C teaches you here
+## Headers: what C teaches you here
 
 ```c
 #include <stdio.h>   // printf, FILE
@@ -66,7 +46,7 @@ In C:
 
 ---
 
-## 4️⃣ Conditional compilation (`#if defined(...)`)
+## Conditional compilation (`#if defined(...)`)
 
 Example:
 
@@ -92,7 +72,7 @@ This is how *real* portable C software works (git, curl, openssh).
 
 ---
 
-## 5️⃣ The most important function in the file
+## The most important function in the file
 
 ```c
 static char *dup_or_unknown(const char *s)
@@ -121,12 +101,9 @@ free(user);
 No special cases.
 No defensive `if (ptr)` checks.
 
-**Lesson:**
-👉 In C, helper functions enforce invariants so callers stay clean.
-
 ---
 
-## 6️⃣ Dynamic allocation patterns (CRITICAL)
+## Dynamic allocation patterns (CRITICAL)
 
 Example:
 
@@ -151,12 +128,9 @@ Contrast this with C++:
 * No smart pointers
 * No safety net
 
-**Lesson:**
-👉 In C, *ownership is a social contract*, not a language feature.
-
 ---
 
-## 7️⃣ Why no global buffers?
+## Why no global buffers?
 
 You *could* have done:
 
@@ -176,12 +150,9 @@ Dynamic allocation makes your functions:
 * Testable
 * Library-quality
 
-**Lesson:**
-👉 Globals are easy — dynamic ownership is correct.
-
 ---
 
-## 8️⃣ Reading system information in C
+## Reading system information in C
 
 Each platform teaches a lesson:
 
@@ -206,12 +177,9 @@ sysctl()
 * Buffer-size negotiation
 * Integer & struct-based data
 
-**Lesson:**
-👉 C doesn’t abstract the OS — it exposes it.
-
 ---
 
-## 9️⃣ Time handling (classic C pain point)
+## Time handling (classic C pain point)
 
 ```c
 time_t now = time(NULL);
@@ -224,12 +192,9 @@ Why this matters:
 * You *never* subtract times directly
 * `difftime()` handles portability
 
-**Lesson:**
-👉 In C, use the standard library *exactly as intended*.
-
 ---
 
-## 🔟 The `main()` function: clean by design
+## The `main()` function: clean by design
 
 ```c
 char *user = get_user();
@@ -246,39 +211,3 @@ Notice:
 
 All complexity lives *outside* `main()`.
 
-**Lesson:**
-👉 In C, `main()` should read like a script.
-
----
-
-## 1️⃣1️⃣ What this code teaches you overall
-
-You’ve learned:
-
-* ✅ How C handles memory *explicitly*
-* ✅ How portability really works
-* ✅ How to design safe APIs in unsafe languages
-* ✅ How Unix exposes system information
-* ✅ How real-world C programs are structured
-
-This is **not beginner C** — this is *professional-grade foundational C*.
-
----
-
-## If you want to go deeper next
-
-From a learning perspective, great next steps would be:
-
-* 🔹 Splitting into `.h` / `.c`
-* 🔹 Writing your own `string_builder`
-* 🔹 Adding error-return variants (`int get_x(char **out)`)
-* 🔹 Making this a reusable library
-* 🔹 Running it under `valgrind` and analyzing output
-
-If you want, I can:
-
-* Rewrite one function *line by line* explaining *every character*
-* Or turn this into a **guided C learning project**
-
-Just tell me how deep you want to go — you’re asking exactly the right questions 👏
-