About the File Manager and System 7.0
About the File Manager and System 7.0 Changes for the new OS version
Most of the features described in this section are available only in system
software version 7.0 or later. To determine which features are available in a
specific operating environment, use the Gestalt function.The availability of
some features depends on the characteristics of the volume rather than on the
system software. To determine which features a volume supports, use the
PBHGetVolParms function. A complete description of how you check for
various new features appears at the beginning of the section en titled
Using the File Manager.
To use this section you must be familiar with the file system documentation.
The File Manager is the part of the Operating System that gives your
application access to data storage devices such as disk drives. You use the
File Manager to create, write, and read files.
To fully exploit system software version 7.0, your application should adopt
two new File Manager features:
the file system specification record, a new convention for identifying
files and directories (see the section en titled
Identifying Files, Directories, and Volumes )
the strategy of updating a stored file by changing the catalog entries
(see, A Simpler Safe-Save Strategy )
The File Manager in version 7.0 also introduces a number of
special-purpose functions that you can use to
search an entire volume quickly, matching entries in almost any of
the catalog information fields, such as file creation date or file length
track files by assigning and resolving file identification numbers
mount volumes
manipulate access-control privileges in foreign file systems
Version 7.0 supplies high-level versions of some functions previously
available only as low-level functions. These functions have been available
historically in some development environments but have not been documented
before in Inside Macintosh.
The PBHGetVolParms function, which reports volume information, has
been expanded and updated to reflect features in version 7.0. Some
File Manager routines have been modified to accommodate file identification
numbers.
System software version 7.0 includes a local version of Apple's file-server
application, AppleShare. This feature allows the user to make some or all of
the files on a local volume available over a network, increasing the chance that
your application may be used in a shared environment. As long as you follow
the standard guidelines for Macintosh programming, your application should
work in a shared environment. If you want to exploit the full power of a shared
environment, follow the guidelines in the section,
File Manager Extensions.
To help you understand and use the version 7.0 File Manager, the first few
sections of this section introduce the new features you should use: the new
convention for identifying files and directories and the new strategy for
updating stored files safely. The "New Special-Purpose Features" section
introduces an assortment of other powerful but more specialized features.
The Using the File Manager section contains instructions for using the
new features of the File Manager to
recognize and use a standard file identification convention
update a stored file safely
search a volume for one or more files or directories
assign and resolve file ID numbers
manipulate the permission information that controls access to files on
volumes controlled by different operating systems, such as A/UX.