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- From: kitchin@lf.hp.com (Bruce Kitchin)
- Newsgroups: comp.os.os2.misc
- Subject: Re: OK, WHY won't EA's get backed up?
- Date: 14 Dec 1992 18:59:37 GMT
- Organization: Hewlett Packard Santa Clara Site
- Lines: 28
- Message-ID: <1gilipINN19p@hpscit.sc.hp.com>
- References: <1992Dec13.062449.4591@gremlin.muug.mb.ca>
- NNTP-Posting-Host: eden.avo.hp.com
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-
- Charles (charles@gremlin.muug.mb.ca) wrote:
- :
- : I keep reading how you can't back up OS/2 with a DOS back up program
- : because the EA's won't get backed up. Does this include FAT as well? If
- : so, why? The EAs are just kept in a seperate file aren't they which will
- : get backed up in a normal backup stream.
- :
-
- The problem is the link between the file and its EA's. A previously
- unused field in the file's directory entry points to the EA's (probably
- an offset into the file containing the EA's). IF, the backup program
- restores the directory entry bit for bit including any 'unused' or
- 'reserved for future expansion' fields, then if the 'EA DATA. SF'
- is restored that was saved at the same time the file was saved, then
- I wouldn't be surprised to see a DOS backup utility work. Unfortunately,
- I'm not sure we can be sure about these points. Some DOS utilities take
- an entire copy of the directory entry while others are 'smarter' and only
- take what they need. The 'smarter' kind is likely to be a disaster
- on OS/2. It is known that some DOS FAT defragmenters do work on
- disks with EA's. They must move intact any fields that it knows nothing
- about.
-
- There are only a couple of ways to be sure. Find out from the developer
- whether they work in a compatible way with EA's. Or test the situation
- on a disk that you can afford to lose in case it doesn't work. Neither
- of these appeal to me. But then I use an Irwin tape backup with software
- that is EA aware and runs under OS/2.
-
-