🚀 go-pugleaf

In message <4dc9o3$cia@nuscc.nus.sg> - phuajooy@iscs.nus.sg (TIE Fighter)
write
s:

Whilst using partition magic I came across an error when doing a check
on a partition which has win95 residing in it.
Something like this : "error 1002 orphaned extended attributes"
Is there a "cure" for this?

-- end of quote --

okay, boot up from OS/2 diskettes or from a maintenance partition (more
later), and do a chkdsk with the  /f option to fix orphaned EAs. Run it twice
to make sure it has been fixed. 

explanation:

Extended Attributes (EAs):

DOS FAT has the following attributes: filename, extension, date, time,
archival bits (a,r,h,s) and  filesize. 

Each file/object/icon has attributes, which ones ? almost anything.
Right-Mouse Click on any icon and  depending on the object, it will have
different attributes, eg. for a folder, attributes will be things  like View,
Icon Bitmap, SOrt or non sort, background, file etc etc etc. for a normal file
object,  attributes will be things like, name, size (those from the FAT above)
as well as icons, dos-settings etc  etc etc ... each object can have an EA up
to 64K.

Now, how does OS/2 store these objects ? Well, it depends on the type of File
System: FAT or HPFS.

Under FAT File System, there is no space in the table to store all the
attributes for a file, only 2-butes  is free space for each file. So, os/2
puts a "pointer" in the two bytes, pointing to a single Hidden file  called
"EA DATA. SF". So the hidden file will contain all the EAs for all the files
in that drive. 

Under HPFS file system, the EAs are combined with the file, so it is very
transparent. 

So how did you get a corrupted/orphaned/cross-linked EA ? 

Well, lets say, you have a file with an EA, eg. a pretty icon. Under OS/2 or
OS/2-DOS if you move the file  to another drive, ie. copy and delete the old
file, the EA for the original file is moved as well. But if  you boot under
pure DOS, and you move the file, ie. copy and delete, poor DOS will not
understand the  concept of EAs and not copy the EAs to the new drive. For the
new file, nothing serious has happened, it  just lost a icon but otherwise,
perfectly usable. For the orginal drive, the EA is still there, ie. the 
attributes are present but no file is pointing to it. If another file so
happen to occupy the space, it  will inherit the new EA. This is dangerous,
and it is a compromise to the file/drive integrity. 

Maintenance Partition:

I have 3 bootable partitions in my OS/2 - DOS, OS/2 and Maintenance Partition
(MP).

My MP is less than 3 MB in partiion size. And it contains a very small text
based OS/2, can't do much  except for me to boot up to do CHKDSK on my main
OS/2 partition. This is cool as you doan have to boot up  from floppies
anymore. How did I create a MP ? Well, first you must have a ready small
parition to work  with, and you will need the file BOOTOS2.ZIP from
hobbes.nmsu.edu /os/textutil/bootos2.zip. This program  will create a bootable
parition from your existing OS/2 partition. 


In essence: 

1. Use HPFS where possible (it is a more elegant solution)
2. Have a Maintenance Parition for emergency boot-ups


Hope this helps

felix eng
singapore os/2 user group