How to declare a pointer to a character array in C?

Question

How do I declare a pointer to a character array in C?

Answer 1

I guess I'll give this answer in parts:

1. Here's a pointer to an array of chars (I assumed a 10-element array):

   char (*x)[10];
   

   Let's break it down from the basics:

   x
   

   is a pointer:

   *x
   

   to an array:

   (*x)[10]
   

   of chars:

   char (*x)[10]
   

2. However, most of the time you don't really want a pointer to an array, you want a pointer to the first element of an array. In that case:

   char a[10];
   char *x = a;
   char *y = &a[0];
   

   Either x or y are what you're looking for, and are equivalent.

3. Tip: Learn about cdecl to make these problems easier on yourself.

Answer 2

You can declare it as extern char (*p)[];, but it's an incomplete type. This is of course because C has no "array" type generically that is a complete type; only arrays of a specific size are complete types.

The following works:

extern char (*p)[];

char arr[20];

char (*p)[20] = &arr;  // complete type now: p points to an array of 20 chars