a UCS-4 encoded string
the maximum length (number of characters) of str to use. If len < 0, then the string is nul-terminated.
location to store number of bytes read, or NULL. If an error occurs then the index of the invalid input is stored here.
location to store number of gunichar2 written, or NULL. The value stored here does not include the trailing 0.
a pointer to a newly allocated UTF-16 string. This value must be freed with g_free(). If an error occurs, NULL will be returned and error set.
GException on failure.
Convert a string from UCS-4 to UTF-16. A 0 character will be added to the result after the converted text.