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Comment by 36erhefg | Hacker News Reader

Array is not a pointer. Your description of indexing is not correct, neither is the phrase "array pointer" you invented. The machine code produced will calculate the offset differently for a pointer and an array.

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Let me clarify with an example. Suppose you have an array:

  int a[10]

There is a section of memory of size sizeof(int) * 10 somewhere, and the variable a is a * int that points to that section. When someone does this:

  int x = a[2]

It is equivalent to:

  int x = *(a+(sizeof(int)*2))

When I said "array pointer" in my previous comment, all it meant was the memory address that the variable (which is an array) points to (in the example, the variable "a")

Edit: missing paren

a is a label, or an alias of a memory address. It is not a pointer. ( Your third example has a mistake, the correct increment is: a+2, because pointer arithmetic increments in object size not byte size )

Read this:http://eli.thegreenplace.net/2009/10/21/are-pointers-and-arr...

Interesting read. Thanks :)

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