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+This document describes the implementation of the RTEMS filesystem
+infrastructure. This infrastructure supports the following
+- Mountable file systems
+- Hierarchical file system directory structure
+- POSIX compliant set of routines for the manipulation of files and directories
+- Individual file and directory support for the following:
+ # Permissions for read, write and execute
+ # User ID
+ # Group ID
+ # Access time
+ # Modification time
+ # Creation time
+- Hard links to files and directories
+- Symbolic links to files and directories
+This has been implemented to provide the framework for a UNIX-like
+file system support. POSIX file and directory functions have been
+implemented that allow a standard method of accessing file, device and
+directory information within file systems. The file system concept that
+has been implemented allows for expansion and adaptation of the file
+system to a variety of existing and future data storage devices. To this
+end, file system mount and unmount capabilities have been included in this
+RTEMS framework.
+This framework slightly alters the manner in which devices are handled
+under RTEMS from that of public release 4.0.0 and earlier. Devices that
+are defined under a given RTEMS configuration will now be registered as
+files in a mounted file system. Access to these device drivers and their
+associated devices may now be performed through the traditional file system
+open(), read(), write(), lseek(), fstat() and ioctl() functions in addition
+to the interface provided by the IO Manager in the RTEMS Classic API.
+An In-Memory File System (IMFS) is included which provides full POSIX
+filesystem functionality yet is RAM based. The IMFS maintains a
+node structure for each file, device, and directory in each mounted
+instantiation of its file system. The node structure is used to
+manage ownership, access rights, access time, modification time,
+and creation time. A union of structures within the IMFS nodal
+structure provide for manipulation of file data, device selection,
+or directory content as required by the nodal type. Manipulation of
+these properties is accomplished through the POSIX set of file and
+directory functions. In addition to being useful in its own right,
+the IMFS serves as a full featured example filesystem.
+The intended audience for this document is those persons implementing
+their own filesystem. Users of the filesystem may find information
+on the implementation useful. But the user interface to the filesystem
+is through the ISO/ANSI C Library and POSIX 1003.1b file and directory
+.. COMMENT: COPYRIGHT (c) 1988-2002.
+.. COMMENT: On-Line Applications Research Corporation (OAR).
+.. COMMENT: All rights reserved.