From d45d5ae14c0b50be5d615a9e9b883c0b0822e307 Mon Sep 17 00:00:00 2001
From: Jet Hughes <jethughes0@gmail.com>
Date: Mon, 5 Sep 2022 10:04:46 +1200
Subject: [PATCH] vault backup: 2022-09-05 10:04:46

---
 content/notes/11-struct-and-union.md     | 42 ++++++++++++++++++++++--
 content/notes/12-pointers-to-routines.md | 10 ++++++
 content/notes/cosc-204.md                |  3 +-
 3 files changed, 51 insertions(+), 4 deletions(-)
 create mode 100644 content/notes/12-pointers-to-routines.md

diff --git a/content/notes/11-struct-and-union.md b/content/notes/11-struct-and-union.md
index be1a21244..7eb68c81e 100644
--- a/content/notes/11-struct-and-union.md
+++ b/content/notes/11-struct-and-union.md
@@ -3,6 +3,10 @@ title: "11-struct-and-union"
 aliases: 
 tags: 
 - cosc204
+- lecture
+sr-due: 2022-09-08
+sr-interval: 3
+sr-ease: 250
 ---
 
 # Struct
@@ -54,8 +58,8 @@ location.y = 1;
 copy the members including pointers
 - but not the things the pointers point to
 
-![shallow copy example 1](https://i.imgur.com/w3B3ce0.png)
-![shallow copy example 2](https://i.imgur.com/mL5QION.png)
+![shallow copy example 1|200](https://i.imgur.com/w3B3ce0.png)
+![shallow copy example 2|400](https://i.imgur.com/mL5QION.png)
 
  both point to the same memory location.
 when you change one - they both change.
@@ -128,7 +132,39 @@ queue *queue_new(void){
 ```
 
 enqueue
-
 ![enqueue code|400](https://i.imgur.com/suaKfi9.png)
 
+dequeue
+![dequeue code|400](https://i.imgur.com/u3mKX5R.png)
+
+# Structs as view
+```
+typedef struct q_item {
+	int value;             //4-byte integer
+	struct q_item *next;   //8-byte pointer
+} queue_item;
+```
+
+![](https://i.imgur.com/ObfIzew.png)
+
+struct is a view where the members are laid out consecutively
+
+# Union
+multiple views of the same memory
+- each line in the declaration is a different view
+
+```
+typedef union {
+	struct {
+		uint8_t a, b, c, d;
+	};
+	uint32_t integer;
+} two_views;
+```
+
+![diagram|100](https://i.imgur.com/qL8KnW5.png)
+
+## endianess
+big-endian vs little-endian
+some computer store the most significatn byte first, other store the least significant byte first
 
diff --git a/content/notes/12-pointers-to-routines.md b/content/notes/12-pointers-to-routines.md
new file mode 100644
index 000000000..a4934745a
--- /dev/null
+++ b/content/notes/12-pointers-to-routines.md
@@ -0,0 +1,10 @@
+---
+title: "12-pointers-to-routines"
+aliases: 
+tags: 
+- cosc204
+- lecture
+---
+
+# compiler
+converts high level language description of program into machine code description of the program
diff --git a/content/notes/cosc-204.md b/content/notes/cosc-204.md
index 396af32f7..8deb9ab7d 100644
--- a/content/notes/cosc-204.md
+++ b/content/notes/cosc-204.md
@@ -38,7 +38,8 @@ tags:
 - [06-6809-programming](notes/06-6809-programming.md)
 - [07-6809-advanced](notes/07-6809-advanced.md)
 - [08-intro-to-c](notes/08-intro-to-c.md)
-- 
+- [11-struct-and-union](notes/11-struct-and-union.md)
+
 # Archive
 
 # Info