Path: utzoo!mnetor!uunet!husc6!bloom-beacon!gatech!udel!rochester!ritcv!ritcsh!dani
From: dani@ritcsh.UUCP (Dani Kadoch)
Newsgroups: comp.sys.ibm.pc
Subject: Re: 5.25 and 3.5 inch diskettes
Message-ID: <1635@ritcsh.UUCP>
Date: 8 Apr 88 00:17:32 GMT
References: <976@tjalk.cs.vu.nl>
Reply-To: dani@ritcsh.UUCP (Dani Kadoch)
Organization: Computer Science House @ RIT, Rochester, NY
Lines: 31
Keywords: diskcopy
Summary: Can't DISKCOPY

In article <976@tjalk.cs.vu.nl> se6@cs.vu.nl (Houweling E) writes:
> Does anyone know if it is possible to diskcopy a 5.25 inch diskette
> onto a 3.5 inch floppy ? MS-DOS diskcopy won't do it, but in my opinion
> it should be possible to copy a disk to a HIGHER density diskette like this:
>  >> READ sector #0, WRITE sector #0, READ sector #1, WRITE sector #1,...etc..
> This should be possible on a machine which has both kinds of drives built-in,
> shouldn't it ? If this is NOT possible, why not ?

No, it is not possible for a program to copy disks in that way.  The
way DOS works is that for each different type of disk it accepts, it
has a different scheme of writing to it.  The size of the File
Allocation Table (FAT) varies in different formats, for example.  The
FAT is simply a list of the clusters in use, and as you may realize, a
720K 3.5" disk has more clusters than a 360K 5.25" disk, hence a
different size for the FAT.  Another thing that changes size is the
root directory, which simply keeps the names, location and other
information about each file in \.  Again, the larger the capacity of
the disk, the bigger the root directory (generally.)

If you want to copy between formats, the easiest way (in my opinon) is
to use 'XCOPY A:\ B: /S' which will copy the root and all other
directories from A: to B:.  It will also automatically create all
subdirectories needed in B:.  However, this is not a completely
infallible method, since hidden files and subdirectories will NOT be
copied.  I hope this helps, anyway.

-- 
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> Dani Kadoch @ Computer Science House @ Rochester Institute of Technology    <
> UUCP: {allegra,seismo}!rochester!ritcv!ritcsh!dani   BITNET: dnk8842@ritvax <
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