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.
|$00||4||Magic string: |
|$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.
|$6C||4||Total file size, in bytes, excluding the header.|
|$70||2||XMODEM chunk count - above file size divided by 128, then rounded up.|
|$74||4||Modification time - seconds since January 1st, 2000.|
|$7C||4||Offset to resource data, bytes excluding header; -1 if not present.|
15 bit 8 7 bit 0 ---- ---- ---- ---- ???? ???? ??i? ?rwx | ||| | ||+- Execute | |+-- Write | +--- Read +------- Intermediate library
- XMODEM transfers are performed in 128-byte blocks; this allows fetching the file's metadata as the first block