Inside Macintosh: Files /

Chapter 5 - Disk Initialization Manager

About the Disk Initialization Manager

The Disk Initialization Manager is the part of the Macintosh Operating System that manages the process of initializing disks. This package accepts requests to initialize a disk and translates them into control calls for the corresponding disk driver. The Disk Initialization Manager itself does not perform the low-level formatting or verification of the disk; instead, it simply manages the communication between the software requesting that a particular disk be initialized and the appropriate disk driver.

Note

In theory, you can use the Disk Initialization Manager to initialize any writable disk drive. In practice, however, most SCSI disk drivers ignore formatting control calls. Instead, low-level disk operations such as formatting and verification are usually performed by a utility program supplied with the disk. As a result, this chapter assumes that the disk to be initialized is a 3.5-inch floppy disk or an Apple Hard Disk 20SC, all of which are accessed through the Disk Driver.

Usually, the Finder or the Standard File Package calls the Disk Initialization Manager when the user inserts an uninitialized disk. Occasionally the user will insert a disk when your application is frontmost. At that time, the Operating System generates a disk-inserted event. If your application has not masked out such events, it receives an event record for that event when it makes an event call and no events with higher priority are pending. You then need to determine whether the inserted disk is valid (as indicated by a value in the event record). If the disk is not valid, you should call the Disk Initialization Manager to allow the user to initialize the disk or, if desired, eject it.

If your application masks out disk-inserted events, the event stays in the event queue until your application calls the Standard File Package (which automatically processes disk-inserted events) or until the current application can handle disk-inserted events. In general, it's best not to mask out disk-inserted events and to handle them as described later in this chapter; otherwise, the user is likely to become confused when, after inserting an uninitialized or damaged disk, no disk icon appears on the desktop and no standard disk initialization dialog box appears. (Icons of initialized and undamaged disks always appear on the desktop, even if the current application ignores disk-inserted events.)

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Subtopics

Disk Initialization

The Disk Initialization User Interface

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