valid_big5head    201 ext/mysqlnd/mysqlnd_charset.c 	return (valid_big5head(*(start)) && (end - start) > 1 && valid_big5tail(*(start + 1)) ? 2 : 0);
valid_big5head    207 ext/mysqlnd/mysqlnd_charset.c 	return (valid_big5head(big5)) ? 2 : 1;