From: Darren Senn (sinster@tioga.ucsc.edu)
Date: 05/27/92


From: sinster@tioga.ucsc.edu (Darren Senn)
Subject: Re: Simple help mounting a floppy needed
Date: 27 May 1992 19:58:22 GMT

In article <1992May27.190330.528@bronze.ucs.indiana.edu>, wdueber@copper.ucs.indiana.edu (Bill Dueber) writes:
> I tried rawriting the mtools-n.tar file to a high-density 1.44 M floppy,
> and then tried to mount it with
>
> mknod /dev/fda b 2 28 <-- Is this right for a 1.44M floppy in a:?
> mount /dev/fda /floppya
>
> And I continuously get a magic number error on the mount attempt. If I
> do a mkfs to /dev/fda everything works fine; of course, my file is no
> longer on the disk in that case, and I'm stuck with an empty floppy mounted
> under /floppya.

You can't mount a floppy to which you've written a tar file. You simply
access the floppy with tar. If a particular file is advertised as a
disk image, then you can rawrite it to a floppy, and then mount the
floppy -- otherwise no.

To access a tar file you've written to a floppy:
        tar -tvf /dev/fd0
         ^ ^^^ ^
         | ||| +-- Device for your floppy goes here (/dev/floppya above)
         | ||+-------- This tells tar to access a file other than /dev/rmt8
         | |+--------- Verbose listing
         | +---------- Type the directory of a tar file
         +-------------- Tape ARchiver: program to access tar files.

The big leap that you have to make is realizing that under UNIX, everything's
a file: devices, memory, and of course files. If you've written some data
to a device, then the file that names that device actually names the _data_
in that device. So the [special] file /dev/fd0 isn't so much floppy drive
0, as the data on the disk in floppy drive 0.

-- 
Darren Senn                                            Phone:    (408) 479-1521
sinster@scintilla.capitola.ca.us                       Snail: 1785 Halterman #1
Wasurenaide -- doko e itte mo soko ni anata wa iru yo.     Santa Cruz, Ca 95062