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Full Discussion: How raw disks are read?
Top Forums UNIX for Advanced & Expert Users How raw disks are read? Post 302802765 by methyl on Saturday 4th of May 2013 06:13:54 PM
Old 05-04-2013
Point: With modern hardware a "raw disc" can be multiple physical discs which the Operating System sees as one physical disc.

Some research ideas:

Consider the case of a virgin disc. There are no filesystems unless your software creates a filesystem. You can write or read whatever you like within the physical dimensions of the disc.

The very basic filesystems follow the pattern of the original IBM tape format VOL1 HDR1.

For research purposes it is worth a look at CAFS (Content Addressable File Store). That's the way to use a raw disc! It's so much better than "Binary Tree", "Hash Random" or "Index Sequential" file systems when dealing with disorganised data.
 

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LEARN ABOUT DEBIAN

f1tattoo

f1tattoo(1)							   f1tattoo 0.7 						       f1tattoo(1)

NAME

       f1tattoo - disc T@2 feature for Yamaha F1 CD-RW devices

SYNOPSIS

       f1tattoo [-l] [-h]
       f1tattoo -d DEVICE [-c] [-s] [--tattoo-test]
       f1tattoo -d DEVICE --tattoo-raw <file.raw>
       f1tattoo -d DEVICE --tattoo-png <file.png>

DESCRIPTION

       f1tattoo is the linux console tool to use the Yamaha disc T@2 feature. You won't get satisfying results on Phtalocyanin dye.

FEATURES

       You can disc T@2 with these drives:
       Yamaha F1 CD-RW, Yamaha F1DX

DEVICE

       can be an IDE, SCSI, SATA, USB or FireWire connected optical drive. Not all SATA controller support all Plextor features.

       Linux:
       /dev/hdX: IDE device
       /dev/scdX: Linux 2.4: SATA, SCSI, USB device, or IDE device via ide-scsi emulation
       /dev/srX: Linux 2.6: IDE device via new ATA layer, SCSI or USB device

       OpenBSD/NetBSD:
       /dev/rcdX

       FreeBSD:
       /dev/cd: SCSI device
       /dev/acd: ATA device

       MacOS X:
       /dev/disk:

       win32:
       C:,D:,E:, ... X:,Y:,Z:

OPTIONS

       -l, --scanbus
		 scan busses for all available CD and DVD devices.

       -h, --help
		 help. show available options.

       -c, --current
		 show current drive settings of selected device

       -s, --supported
		 show supported features of selected device

       --tattoo-test
		 write DiscT@2 test image

       --tattoo-raw tattoo.raw
		 write DiscT@2 using raw data from tattoo.raw file

       --tattoo-png tattoo.png
		 write DiscT@2 using png image from tattoo.png file	      check if f1tattoo compiled with png support using --help option

       -v, --verbose
		 give verbose output

EXAMPLES

       f1tattoo -l
		 list all available CD- and DVD-devices

       f1tattoo -d /dev/hdc --tattoo-raw filename.raw
		 writes DiscT@2 using filename.raw file on media in device /dev/hdc

       please report man page improvements to T.Maguin@web.de

Gennady ShultZ Kozlov						  10. April, 2009						       f1tattoo(1)
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