Differences

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--- notes:data [2018/08/19 10:15] – wedge
+++ notes:data [2018/10/24 23:39] (current) – [URLs] ktodd3
@@ Line 6: / Line 6: @@
 ======Projects======
+dsi0
+ael0
 ======URLs======
+Binky Pointer Video:
+[[https://www.youtube.com/watch?v=f-pJlnpkLp0|Binky Pointer Video]]
+[[https://www.learn-c.org/en/Linked_lists|Basic linked list tutorial ]]
 ======Notes======
+====Pointers:====
+char x = 0;
+char -> 1 byte (8 bits)
+Default char -> signed (2^8 -> 256 -> -128, +127 [one is used for positive/negative value])
+the asterisk (*) indicates a "pointer"
+    signed char *y = NULL;
+                ^
+(void*)0
+Void pointers are raw memory
+    |0|
+    ---
+    x
+xdeadbeef
+       |NULL(0)|
+       ---------
+       y
+xcoffee
+Access an address with &
+Make y = deadbeef without using "deadbeef" by using the address (&) my man.
+   y = &x
+Now, y's data is the address of x.
+x contains the data '0'
+If we do this:
+    |0|
+    ---
+    x
+xdeadbeef  <- address
+       |0xdeadbeef|
+       ------------
+       y
+xcoffee <- address
+   x = 7;
+   *y = 13;
+Then:
+    |13|
+    ----
+    x
+xdeadbeef  <- address
+       |0xdeadbeef|
+       ------------
+       y
+xcoffee <- address
+x is now 13 because y is x's address, and you 'pointed' 13 to the address. Ill, dog.
+Double pointers are arrays or whatever
+    |          |
+    ------------
+    z
+    signed char **z = NULL;
+So we're gonna give this some garbage
+    |0xcoffee|
+    ----------
+    z
+xc05fefe
+And do nothing with it because we kind of just stopped I think.
+Memory addresses are 8 bytes on 64 bit linux systems.
+bytes on 32 bit linux systems.
 ======Other======