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Date: Tue, 1 Apr 1997 14:23:10 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199704010423.OAA04493@godzilla.zeta.org.au>
To: dbx@atmos.washington.edu, freebsd-bugs@freefall.freebsd.org
Subject: Re: kern/3156: Floppy disk copy freezes
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>     Also, you should never, _never_ use the block device for raw file
>     data.
> 
> When I use the character device for the floppy copy, everything works
> smoothly.  Maybe my setup is the prime example of why one "should never,
> _never_ use the block device for raw file data."  :(

Did you use the same block size (2K) that is used for the block device?
dd's default block size of 512 bytes is too small for almost everything
except floppies (it is adequate for floppies, at least on machines
at least as fast as a 486/33, since floppies are so slow).  The block
device's fixed block size of 2K is also too small for almost everything.

Bruce