Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-tis!ames!mailrus!cornell!uw-beaver!mit-eddie!bbn!spdcc!gnosys!gst
From: gst@gnosys.UUCP (Gary S. Trujillo)
Newsgroups: comp.sys.att
Subject: Re: Minor fix to Mtools patch for 3.5" disks
Message-ID: <57@gnosys.UUCP>
Date: 26 Aug 88 17:52:39 GMT
References: <611@bacchus.UUCP> <56@gnosys.UUCP> <320@uncle.UUCP>
Reply-To: gst@gnosys.UUCP (Gary S. Trujillo)
Distribution: na
Organization: gst's 3B1 - Somerville, Massachusetts
Lines: 28

In article <320@uncle.UUCP> jbm@uncle.UUCP (John B. Milton) writes:
>In article <56@gnosys.UUCP> gst@gnosys.UUCP (Gary S. Trujillo) writes:
>>In article <611@bacchus.UUCP> darren@bacchus.UUCP (Darren Friedlein) writes:
>>>...
>>>One thing I'd like to find is a program like MsdosF.sh that will format
>>>3.5" disks.  Anyone know how to do this?
>>
>>For that matter, does anyone know how to format 5.25" floppies at 360K?
>>Far as I know, /usr/bin/MsdosF.sh will only format 320K (8-sector) disks.
>
>Well, too bad. The UNIX driver will only format (or use) an even number of
>sectors...

But don't standard MS-DOS floppies have 9 sectors?  I can read and write
them fine using either mtools or the DOS-73 coprocessor.

Shortly after posting my question, I got a very detailed response from
Roger Abrahams at Marquette University, going into basic theory of operation
of floppy drives and what all is actually on a floppy disk besides the actual
data.  Not only did Roger point out that one could format a 10-sector disk
with nine sectors actually allocated, but gave the command for doing it:

	md_format -9 /dev/rfp020

("md_format" is normally called from /usr/bin/MsdosF.sh)

-- 
Gary S. Trujillo			      {linus,bbn,m2c}!spdcc!gnosys!gst
Somerville, Massachusetts		     {icus,ima,stech,wjh12}!gnosys!gst