Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!apple!stevec
From: stevec@Apple.COM (Steve Christensen)
Newsgroups: comp.sys.mac.programmer
Subject: Re: SCSI Help
Message-ID: <9927@goofy.Apple.COM>
Date: 24 Aug 90 19:10:06 GMT
References: <917@beguine.UUCP>
Organization: Apple Computer Inc., Cupertino, CA
Lines: 29

In article <917@beguine.UUCP> Eliot.Henry@samba.acs.unc.edu writes:
>Help! I am writing a program to completly erase disks. I need to access the
>hard drive on a sector level. Do i need to figure out how to use the SCSI
>manager? Can I use the same lowlevel calls as on floppies but
>use the appropriate driverefnum and driver num? Any help would be
>greatly appreciated: especially sample source code!

If all you want to do is write all zeroes to all blocks on the disk, then
just make write requests to the driver.  You can do it in a simple loop
something like this:

	allocate a 512 byte block and fill it with zeroes
	for blockNum = 1 to NumberOfBlocks do
	  write the 512 byte block to drive block blockNum

OK, so you wanted real code, but you get the idea.

steve  :-)

-- 
____________________________________________________________________

  Steve Christensen             Internet:   stevec@goofy.apple.com
  Apple Computer, Inc.          AppleLink:  STEVEC
  20525 Mariani Ave, MS 81-CS   CompuServe: 76174,1712
  Cupertino, CA  95014

  "You just contradicted me."  "No I didn't."
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