forked from Imagelibrary/rtems
73 lines
2.1 KiB
Plaintext
73 lines
2.1 KiB
Plaintext
@c
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@c COPYRIGHT (c) 1988-1998.
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@c On-Line Applications Research Corporation (OAR).
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@c All rights reserved.
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@c
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@c $Id$
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@c
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@ifinfo
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@node Preface, , Top, Top
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@end ifinfo
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@unnumbered Preface
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The following file system capabilities have been added to the existing
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RTEMS system:
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@itemize @bullet
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@item Mountable file systems
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@item Hierarchical file system directory structure
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@item POSIX compliant set of routines for the manipulation of files and directories
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@item Individual file and directory support for the following:
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@enumerate
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@item Permissions for read, write and execute
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@item User ID
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@item Group ID
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@item Access time
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@item Modification time
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@item Creation time
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@end enumerate
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@item Hard links to files and directories are supported
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@item Symbolic links to files and directories are supported
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@end itemize
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These enhancements have been made to provide the framework for `UNIX like'
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file system support. The POSIX file and directory functions have been
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implemented to allow a standard method of accessing file, device and
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directory information within the file system. The file system concept that
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has been implemented allows for expansion and adaptation of the file
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system to a variety of existing and future data storage devices. To this
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end, file system mount and unmount capabilities have been included in this
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RTEMS framework.
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This framework slightly alters the manner in which devices are handled
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under RTEMS. Devices that are defined under a given RTEMS configuration
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will now be registered as files in a mounted file system. Access to these
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devices and their associated device handlers will be obtained through the
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traditional file system open(), read(), write(), lseek(), fstat() and
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ioctl() functions.
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A node structure is maintained for each file, device, and directory in the
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file system. The node structure is used to manage ownership, access
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rights, access time, modification time, and creation time. A union of
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structures within the nodal structure provide for manipulation of file
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data, device selection, or directory content as required by the nodal
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type. Manipulation of these properties is accomplished through the POSIX
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set of file and directory functions.
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