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To decode the expression char (*(*x())[5])()

         x          : x is a
         x()        : function
        *x()        : returning pointer to
       (*x())[5]    : a 5-element array of 
      *(*x())[5]    : pointer to
     (*(*x())[5])() : function
char (*(*x())[5])() : returning char

They are NOT the same, despite what people say!

// Example of char array vs char pointer
char *str1 = "Foo"; // Pointer. "Foo" resides in TEXT-section
char str2[] = "Bar"; // Array. "Bar" resides in RAM, copied to DATA section during C-startup
 
str1[2] = 'O'; // Illegal, undefined behaviour
str2[2] = 'R'; // This is fine, it alters content of RAM

uint8_t const *foo; // Points at constant. Can't change the value that foo points at.
const uint8_t *foo; // Same as above.
uint8_t *const foo; // Constant pointer. Can't change the address it is holding.

stdint.h has definitions of uint8_t etc.

inttypes.h has definitions of PRIu8 etc, for use with printf and scanf.

This site lists all available macros and types.

#include <stdint.h>
#include <inttypes.h>
 
...
 
  printf("Printing a uint8_t: %" PRIu8 " woop woop!", var8bit);

#define STRINGIFY_(X) #X
#define STRINGIFY(X) STRINGIFY_(X)
#define PING() debug_print_str(__FILE__ " : " STRINGIFY(__LINE__) "\n")