TITLE
    System 7, Mac OS 8: Limitations of the Finder
Article ID:
Created:
Modified: 		11574
2/12/93
5/5/00
TOPIC

    This article gives the limitations of the Finder in System 7 and Mac OS 8.

DISCUSSION

    Finder Limits
    • Number of open files: 346
    • Number of Apple Menu Items: 52 (More items can added, but only 52 appear in the Apple Menu.)
    • Number of files supported by the Desktop: Unlimited (limited to the available disk space -- see Mac OS Standard format limit)
    • Number of applications in memory: The Finder does not limit applications, but available RAM does
    • Number of volumes available on the Desktop: 32
    • Number of items in a folder by list view: Up to 32 000 depending on the computer and RAM. (See the note at the bottom of this article.)
    • Number of resources in the System File: 32 767 or 16 MB
    • Number of System Extensions or Control Panels that can be loaded into memory: The Finder does not limit these, but hard disk space and RAM can limit them
    • RAM allocated to an application with Finder = 999 999 K
    • The Finder supports 24-bit color, but icons are only 8-bit
    • QuickDraw supports 48-bit color, but the current operating system maximum is 32-bit color
    • Disk cache: 32 KB per megabyte of installed RAM

    Mac OS Standard Format Limits
    • 64K items or 65 536 items per volume
    • The maximum length of a pathname under the Finder--including the Volume and Folder--is 255 characters, including colons

    For example: InternalHD:Folder1:Folder2:Filename = 35 characters

    "Inside Macintosh, Volume IV" states that there is no limit to levels of subdirectories. Because of pathname limitations, it is not always possible to specify a file using its full pathname.

    This limitation has nothing to do with the Finder; it is a limitation of the file system.

    Note: With System 7.x, attempting to view many files in one window, something between 500 to 1500 files, creates very slow opening times and dropout viewing issues. The specific number depends on RAM and computer. With Mac OS 8.x, it is possible to view as many as 32 766 files, though it is dependent upon RAM available, and performance is significantly degraded.

Document Information
Product Area: Mac OS System Software
Category: General OS
Sub Category: General Topics
Keywords: sys7

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