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A couple of questions

I had a couple of questions regarding SFS; thing that AFAIK aren't (explicitely) stated in the spec nor on the wiki:

  • What happens if the index area turns out to be too small to create a new entry? I assume the most feasible option would be to let it grow downwards (i.e. take space from the Free Space area).
  • It is not uncommon for the Starting Marker entry (the one closest to the start of the disk) to not be aligned on BytesPerSector boundaries (e.g. at 128 bytes from a sector). The bytes before the starting marker (if any), are these actually part of the Free Area?

--Creature 21:06, 4 September 2010 (UTC)

  • Please ask on the forums, few people watch this place.
  • The index area is indeed grown when it is too small. The free space is designed so that it can be eaten away from both the front side (file data) and the rear side (index data). A similar description is in the specification.
  • Since the data section is block-aligned, you can't sensibly use the partial block leading the index. Doing so would result in an overlap: the last block of the file would use the same space as the index does, and you can't write out single blocks without having a special case everywhere. Similarly, the specification elaborates as follows: (emphasis mine)
The end of the free space area is determined by subtracting the size of the index 
area from the total size of the media and rounding it down to the nearest block size.
- Combuster 09:26, 6 September 2010 (UTC)
My apologies for asking this here, I can't even remember why I posted it here and not on the forums (or asked it on IRC). There were a couple of other questions I wanted to ask, but I seem to have forgotten them. I'll ask them on IRC/the forums if I manage to remember them. Thanks for the quick answers ;). --Creature 09:49, 6 September 2010 (UTC)


I think it should be noted somewhere that there are other file systems known by the abbreviation SFS, such as AROS's Smart File System, which are totally unrelated to this SFS

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