cur022@zodiac.ukc.ac.uk (Bob Eager) (06/17/90)
I just installed version 1.2, and it added all those extended attributes. Since I also use DOS on the same disk, they won't all stay around, and in any case I have another partition the installation procedure didn't add EAs to. Does anyone know how to do the automatic addition of EAs to any specified disk? Without running installation all through again? Thanks in advance ---------------------+----------------------------------------------------- Bob Eager | University of Kent at Canterbury rde@ukc.ac.uk | +44 227 764000 ext 7589 ---------------------+----------------------------------------------------- *** NB *** Do NOT use the return path in the article header *************** ---------------------------------------------------------------------------
alistair@microsoft.UUCP (Alistair BANKS) (07/17/90)
OS/2 does not 'add extended attributes' as a capability to a disk. Extended Attributes are down-compatible with the DOS FAT format - OS/2 Creates them as needed on any FAT disk and they are invisible to DOS programs. To understand this you should realise that EAs owned by a file or directory on a FAT disk are physically stored in disk space owned by the hidden, system, read-only file stored in the root called "EA DATA. SF". The EA data is pointed to by reserved bytes in the FAT directory entry structure. This file should never be manipulated directly. You should use the EA APIs in the OS/2 1.2 toolkit. You may be able to reverse-engineer the mechanism by careful use of a disk sector editor, though the actual format remains unpublished for the time-being. This weird file has to exist to ensure total down-level compatibility. Its name is valid, although very unlikely to be chosen by any previous application. So no installation step is needed. OS/2 will create the EAs and the "EA DATA. SF" file as needed. If you use DOS to delete a file that OS/2 has attached EAs to, then OS2 chkdsk will recognise that those EAs have not been deleted. Never use DOS to delete "EA DATA. SF" or you will have deleted all those EAs OS/2 created for you. DOS file deletion is not a disaster, it just might waste some small disk space. Every now-and-then, in this case, you should run the OS/2 chkdsk, having booted from the OS/2 install diskette, to 'unlock' your C drive, and then chkdsk/f to regain the 'lost' EA space on FAT disks. Alistair Banks OS/2 ISV Group Microsoft
feustel@well.sf.ca.us (David Alan Feustel) (07/20/90)
So should we back up this file along with all the others when we do
file backup?
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USMAIL: Dave Feustel, 1930 Curdes Ave, Fort Wayne, IN 46805-2710alistair@microsoft.UUCP (Alistair BANKS) (07/22/90)
In article <19133@well.sf.ca.us> feustel@well.sf.ca.us (David Alan Feustel) writes: > >So should we back up this file along with all the others when we do >file backup? "EA DATA. SF", like os2ldr, like ibmbio.com is marked read-only, hidden, system. None of these files can be successfully backed up and restored as normal files. They are all position and content sensitive. Extended Attributes should be backed up with the file or directory they belong to. They are read and written using the EA APIs which are a part of OS/2 1.2 and beyond. Alistair Banks OS/2 Group Microsoft