int memcmp_PF(const void *, uint_farptr_t, size_t) __ATTR_PURE__
The memcmp_PF() function compares the first
len bytes of the memory areas
s1 and flash s2. The
comparision is performed using unsigned char operations. It is an equivalent of
memcmp_P() function, except that it is capable working on all FLASH including the
exteded area above 64kB.
The memcmp_PF() function returns an integer less than, equal
to, or greater than zero if the first len bytes of
s1 is found, respectively, to be less than, to
match, or be greater than the first len bytes of
s2.