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The Unix file system (UFS; also called the Berkeley Fast File System, the BSD Fast File System or FFS) is a file system used by many Unix and Unix-like operating systems. It is a distant descendant of the original filesystem used by Version 7 Unix. == Design == A UFS volume is composed of the following parts: * A few blocks at the beginning of the partition reserved for boot blocks (which must be initialized separately from the filesystem) * A superblock, containing a magic number identifying this as a UFS filesystem, and some other vital numbers describing this filesystem's geometry and statistics and behavioral tuning parameters * A collection of cylinder groups. Each cylinder group has the following components: * * A backup copy of the superblock * * A cylinder group header, with statistics, free lists, etc., about this cylinder group, similar to those in the superblock * * A number of inodes, each containing file attributes * * A number of data blocks Inodes are numbered sequentially, starting at 0. Inode 0 is reserved for unallocated directory entries, inode 1 was the inode of the bad block file in historical UNIX versions, followed by the inode for the root directory, which is always inode 2 and the inode for the lost+found directory which is inode 3. Directory files contain only the list of filenames in the directory and the inode associated with each file. All file metadata is kept in the inode. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Unix File System」の詳細全文を読む スポンサード リンク
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