pointer in C and other lang - (early) learning notes

Every variable in any lang is a 3-some -- name + addr + content (but see the post on mutability, initialize etc). http://aelinik.free.fr/c/ch11.htm has a good explanation:


int x;
x = 7;

the variable x now has two values:


Left value: 1000
Right value: 7

Here the left value, 1000, is the address of the memory location reserved for x. The right value, 7, is the content stored in the memory location.
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Now a few simple rules on & and *
rule -- &var1 returns address of var1.
rule -- I don't think &var1 can be on the left side of =
rule -- var1 must be a L-value expression. See http://bigblog.tanbin.com/2011/11/c-func-call-as-l-value-key-points.html

Now suppose we assign ptr1 = &var1

rule -- *ptr1 returns the content of var1. If you print *ptr1, and print var1, you get same.
rule -- *ptr1 can be on the left side of =

I believe *ptr1 == *(&var1) == var1