			   Under support of OS2.Ru, Russian Team OS/2

FreeJFS project by Pasha Shtemenko
==================================

This file contains some practice information about JFS.


Superblocks
-----------

   All work in JFS begins from reading superblocks and bitmaps.
JFS contains two superblocks and bitmaps (main and backup).
   At booting JFS.IFS reads first superblock. If IFS can't
read the first superblock JFS.IFS reads its second copy.

PS: In our practice on volumes, formatted with "/L" switch (long format)
JFS uses the first superblock, otherwise - second superblock.



Dirty Flag
----------

JFS can have three state of dirty flag:
	- "no check"
	- "standart check"
	- "repair check"

ISJ utility from FreeJFS can set dirty flag to "no check" for rescue
your data from damage JFS volume.


National languages locales
--------------------------

JFS operates with filenames in Unicode encoding. If you use
national characters in filenames - you should check that
loading of UNICODE.SYS driver in CONFIG.SYS is called before
loading of JFS.IFS.

--- example ---
DEVICE=X:\OS2\BOOT\UNICODE.SYS
IFS=X:\OS2\FreeJFS.IFS /AUTOCHECK:* /cache:4096 /L:128,128,32
---------------

It's a very serious requirement for correct filenames operating
with national characters.

Of course, you may have standart IBM's bug when all files
with national characters in filenames are stored in "lost+found"
directory after checking disk with CHKDSK. FreeJFS doesn't
have this bug.

P.S. I hear that IBM has fixed this bug in last build of JFS.IFS.



Contacts
--------

FreeJFS e-mail support: freejfs@os2.ru
FreeJFS WWW Page:       http://OS2.Ru/projects/freejfs

Main developer of FreeJFS: Pasha Stemenko


