WonderWitch .fx files

FreyaOS uses XMODEM transfers to send and receive files through the serial port. These transfers do not include any file metadata by default - such as the file's name, size, permissions or creation date. As such, .fx files are used - binary files with a special 128-byte header.

Format

Header contents

Offset	Length	Contents
$00	4	Magic string: #!ws
$04	60	Padding; typically 0xFF.
$40	16	File name; zero-terminated Shift-JIS string.
$50	24	User-friendly file name; zero-terminated Shift-JIS string. FreyaOS displays the first 12 characters in its file selector.
$68	4	?
$6C	4	Total file size, in bytes, excluding the header.
$70	2	XMODEM chunk count - above file size divided by 128, then rounded up.
$72	2	File mode
$74	4	Modification time - seconds since January 1st, 2000.
$78	4	?
$7C	4	Offset to resource data, bytes excluding header; -1 if not present.

File mode

---

15      bit       0
---- ---- ---- ----
???? ???? ??i? ?rwx
            |   ||+- Execute
            |   |+-- Write
            |   +--- Read
            +------- Intermediate library