function transforms a null-terminated string pointed to by
according to the current locale collation if any,
then copies the transformed string
Not more than
characters are copied into
including the terminating null character added.
is set to 0
(it helps to determine an actual size needed
is permitted to be a NULL pointer.
Comparing two strings using
is equal to comparing
two original strings with
does the same, however takes an explicit locale rather than the global