Chapter 1. Introduction

This document describes the SCSI subsystem as the Linux kernel enters the 2.4 production series.

An external view of the SCSI subsystem is the main theme. Material is included to help the system administration of the Linux SCSI subsystem. There are also brief descriptions of ioctl()s and interfaces that may be relevant to those writing applications that use this subsystem. However internal data structures and design issues are not addressed [see reference W2]. To unclutter the presentation, compile options and system calls (including ioctl()s) have been placed in Appendix E. Although not strictly part of the SCSI subsystem, there is also a description of raw devices in Chapter 11.

For those who have no interest in the SCSI subsystem and just want to get their ATAPI cd writer going, see the section called “ATAPI cdroms”. It may also be useful to browse Chapter 2.

This document follows on from one written five years ago by Drew Eckhardt called the SCSI-HOWTO [see reference W7]. That document described the SCSI subsystem in Linux kernel 1.2 and 1.3 series. It is still available from the Linux Documentation Project [LDP, see reference W8] in its "unmaintained" section. Both documents have roughly similar structures although Drew's document has a lot of information on the adapter drivers.

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This document was last altered on 20th June 2003.