TITLE
    Mac OS X Public Beta: File Systems Accessible in the Classic Environment
Article ID:
Created:
Modified: 		106042
10/20/00
10/20/00
TOPIC

    The Classic environment can access Mac OS Standard (HFS), Mac OS Extended (HFS Plus), and UDF formatted disks, while the Mac OS X Public Beta operating system as a whole can also access UFS and NFS file systems.

DISCUSSION

    For the Classic environment to access a disk or file system, two conditions must be met:
    • The Mac OS X Public Beta operating system must be able to recognize the type of disk or file system.
    • Mac OS 9 must work with that type of disk or file system.

    You may imagine that the Mac OS X Public Beta operating system is a filter that sits between the Classic environment and the physical disk you wish to access. The Classic environment can only "see" what is first recognized by the operating system.

    File systems and disk formats recognized by Mac OS X Public Beta
    • Mac OS Standard (HFS)
    • Mac OS Extended (HFS Plus)
    • UNIX File System (UFS)
    • Network File System (NFS)
    • Universal Disk Format (UDF)

    File systems and disk formats recognized by Mac OS 9
    • Mac OS Standard (HFS)
    • Mac OS Extended (HFS Plus)
    • Universal Disk Format (UDF)
    • Microsoft Disk Operating System (MS-DOS)

    How does this affect usage?

    In some configurations, a particular disk may be available in Mac OS X Public Beta but not in the Classic environment. Some disks that work when the computer is started up from Mac OS 9 are not available when started up from Mac OS X Public Beta. Here are some examples of how a device might behave when connected to an Mac OS X Public Beta computer:
      1. HFS Plus-formatted hard drive

      Mac OS X Public Beta recognizes the hard drive. Because Mac OS 9 also works with this disk format, this hard drive is available throughout the Classic and Mac OS X Public Beta environments.

      2. UFS-formatted hard drive

      Mac OS X Public Beta works with the hard drive. But because Mac OS 9 does not recognize UFS, the drive is not available in the Classic environment.

      3. MS-DOS-formatted hard drive

      Even though Mac OS 9 works with MS-DOS, Mac OS X Public Beta cannot recognize this format. Therefore, the drive is not available at all.

    Note: For the current beta release, types of devices recognized when directly connected to the computer may be limited to hard drives, CD/DVD-ROM drives, and DVD-RAM drives. DVD-RAM media in the UDF format will work as a read-only file system in Mac OS X Public Beta. In the Public Beta release, you cannot open an application from a UDF volume. As a workaround, copy the application onto an HFS or HFS Plus volume.

Document Information
Product Area: Mac OS System Software
Category: Mac OS X
Sub Category: General Topics
Keywords: kmosX

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