a UTF-8 encoded string
the maximum length of @str to use, in bytes. If @len < 0, then the string is nul-terminated.
location to store number of bytes read, or %NULL. If %NULL, then %G_CONVERT_ERROR_PARTIAL_INPUT will be returned in case @str contains a trailing partial character. If an error occurs then the index of the invalid input is stored here.
location to store number of characters written or %NULL. The value here stored does not include the trailing 0 character.
a pointer to a newly allocated UCS-4 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 UTF-8 to a 32-bit fixed width representation as UCS-4. A trailing 0 character will be added to the string after the converted text.