Comparing Pointer types in C

This is a discussion on Comparing Pointer types in C within the C Programming forums, part of the General Programming Boards category; -a1, a2, and a3 are int pointers, right? However, we can 'consider' them to be arrays. Am I okay with ...

  1. #16
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    Wink so what are they already?

    -a1, a2, and a3 are int pointers, right? However, we can 'consider' them to be arrays. Am I okay with this here?

    -a1 and ptr2ptr are NOT of the same type, because ptr2ptr is a pointer to a pointer (it uses double indirection), and a1 is a pointer (using single indirection). ptr2ptr is a bit more 'wild' of a type than a1. ***AM I OKAY WITH THIS HERE***???

  2. #17
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    Quote Originally Posted by sudocat View Post
    -a1, a2, and a3 are int pointers, right? However, we can 'consider' them to be arrays. Am I okay with this here?
    You can use array notation on them, yes. Apart from type (pointer-to-integer vs. array), they are indistinguishable (guaranteed to be laid out in memory exactly the same, for instance).

    Quote Originally Posted by sudocat View Post
    -a1 and ptr2ptr are NOT of the same type, because ptr2ptr is a pointer to a pointer (it uses double indirection), and a1 is a pointer (using single indirection). ptr2ptr is a bit more 'wild' of a type than a1. ***AM I OKAY WITH THIS HERE***???
    "Wild" is not a term I would ever use to describe a variable in a computer program. Put it this way: a1 is a pointer to an integer, it can point to things like "5", and "8". ptr2ptr is a pointer to a (pointer to an integer) -- it can't point to things like "5" and "8", but it can point to things like a1.

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