pointer-4.md

title: More on Pointers IV
layout: two-cols

How to Read C Declarations

The golden rule:

Start at the variable name (or innermost construct if no identifier is present). Look right without jumping over a right parenthesis; say what you see. Look left again without jumping over a parenthesis; say what you see. Jump out a level of parentheses if any. Look right; say what you see. Look left; say what you see. Continue in this manner until you say the variable type or return type.

examples:

int i; // an int
int *a[3];  // an array of size 3 pointers to int
int (*a)[3]; // an pointer of array of size 3 ints
int (*Object_vtable[])(); // an array of pointers to function returning int

::right::

Exercise

Discuss with your teammates and read these declarations out loud:

• char ****q[ 30 ];
• char **(**q)[ 30 ];
• extern int (x)[];
• long (*a[])( char, char );
• int *(*(*(*b)())[10])();
• char *strprt( char (*)( int ), unsigned char );
• int (*const ab[])( unsigned int );