Typedefs for complex data types

Question

I am attempting to understand the underlying mechanics of how C handles complex typedefs, from a syntax perspective.

Consider the following examples below (references in

Answer 1

Simplfying KepaniHaole's rules a bit, it boils down to:

1. Find the left-most identifer
2. Work your way out, remembering that absent explicit grouping by parentheses, function-call () and [] bind before *.
3. Apply recursively to any function parameters.

Thus, T *a[] is an array of pointer tp T, T (*a)[] is a pointer to an array of T, T *f() is a function returning a pointer to T, , and T (*f)() is a pointer to a function returning T.

Taking an example that gives a lot of people heartburn, we can look at the prototype for the POSIX signal function:

void (*signal( int sig, void (*func)( int )))( int );

which reads as

       signal                                          -- signal
       signal(                             )           -- is a function with
       signal(     sig                     )           -- parameter sig
       signal( int sig                     )           --   of type int
       signal( int sig,        func        )           -- and parameter func
       signal( int sig,      (*func)       )           --   of type pointer to
       signal( int sig,      (*func)(     ))           --   a function with
       signal( int sig,      (*func)( int ))           --     an int parameter
       signal( int sig, void (*func)( int ))           --   returning void
     (*signal( int sig, void (*func)( int )))          -- returning a pointer to
     (*signal( int sig, void (*func)( int )))(     )   --   a function with
     (*signal( int sig, void (*func)( int )))( int )   --     an int parameter
void (*signal( int sig, void (*func)( int )))( int )   --   returning void