_toupper
#define toupper(c) (islower(c) ? _toupper(c) : (c))
#define toupper(c) (islower(c) ? _toupper(c) : (c))
extern int _toupper(int);
#define TOUPPER(c) (isascii(c) && islower(c) ? _toupper(c) : c)
#define toupper(c) (islower(c) ? _toupper(c) : (c))
*p = (char)_toupper((int)*p);