【C】Pointer (4) How Pointer Is Described in C Standard?
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Why even professionals write wrong statements or vague descriptions in books or web sites?
Let’s investigate how pointer is defined in the specification.
For example, you can read specification of C language in below URL.
http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf
If you search “pointer” in this files, you may find some funny things.
- 637 hits, too many.
- Even there are 637 hits, it is not clear where “pointer” is clearly defined.
In these circumstances, I recommend search from last, and investigate Index at first. If you search 3 times from the last, you can find
pointer, 6.2.5
on page 547, left column.
http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf#page=547
This Section 6.2.5 page 48 (page number on pdf is 36) is the 1st place where “pointer” itself is explained.
– A pointer type may be derived from a function type, an object type, or an incomplete type, called the referenced type.
A pointer type describes an object whose value provides a reference to an entity of the referenced type.
A pointer type derived from the referenced type T is sometimes called ‘‘pointer to T’’.
The construction of a pointer type from a referenced type is called ‘‘pointer type derivation’’.
These methods of constructing derived types can be applied recursively.
ref: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1256.pdf#page=48
Still confusing. To be honest, when I read this at first time, I could not understand.
I will summarize and explain rigorously in next article.
That’s all for this time.
