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Inode Pointer Structure
The inode pointer structure is a structure adopted by the inode of a file in the Unix File System (UFS) to list the addresses of a file's data blocks. It is also adopted by many related file systems, including the ext3 file system, popular with Linux users. Structure In the past, the structure may have consisted of eleven or thirteen pointers, but most modern file systems use fifteen pointers. These pointers consist of (assuming 15 pointers in the inode): * Twelve pointers that directly point to blocks of the file's data (direct pointers) * One singly indirect pointer (a pointer that points to a block of pointers that then point to blocks of the file's data) * One doubly indirect pointer (a pointer that points to a block of pointers that point to other blocks of pointers that then point to blocks of the file's data) * One triply indirect pointer (a pointer that points to a block of pointers that point to other blocks of pointers that point to other blocks of pointers that then ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ext2-inode , a sport utility truck
{{disambiguation ...
Ext, ext or EXT may refer to: * Ext functor, used in the mathematical field of homological algebra * Ext (JavaScript library), a programming library used to build interactive web applications * Exeter Airport (IATA airport code), in Devon, England * Exeter St Thomas railway station (station code), in Exeter, England * Extended file system, a file system created for Linux * Exton station (Pennsylvania) (Amtrak station code), in Exton, Pennsylvania * Extremaduran language (ISO language code), spoken in Spain * Extremeroller, a former roller coaster at Worlds of Fun, Kansas City, Missouri * Cadillac Escalade EXT The Cadillac Escalade is a full-size luxury SUV engineered and manufactured by General Motors. It was Cadillac's first major entry into the SUV market. The Escalade was introduced for the 1999 model year in response to competition from the Merc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inode
The inode (index node) is a data structure in a Unix-style file system that describes a file-system object such as a file or a directory. Each inode stores the attributes and disk block locations of the object's data. File-system object attributes may include metadata (times of last change, access, modification), as well as owner and permission data. A directory is a list of inodes with their assigned names. The list includes an entry for itself, its parent, and each of its children. Etymology There has been uncertainty on the Linux kernel mailing list about the reason for the "i" in "inode". In 2002, the question was brought to Unix pioneer Dennis Ritchie, who replied: A 1978 paper by Ritchie and Ken Thompson bolsters the notion of "index" being the etymological origin of inodes. They wrote: Additionally, Maurice J. Bach wrote that an inode "is a contraction of the term index node and is commonly used in literature on the UNIX system". Details A file system relies on d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix File System
The Unix file system (UFS) is a family of file systems supported 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 unallocate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Block (data Storage)
In computing (specifically data transmission and data storage), a block, sometimes called a physical record, is a sequence of bytes or bits, usually containing some whole number of records, having a maximum length; a ''block size''. Data thus structured are said to be ''blocked''. The process of putting data into blocks is called ''blocking'', while ''deblocking'' is the process of extracting data from blocks. Blocked data is normally stored in a data buffer, and read or written a whole block at a time. Blocking reduces the overhead and speeds up the handling of the data stream. For some devices, such as magnetic tape and CKD disk devices, blocking reduces the amount of external storage required for the data. Blocking is almost universally employed when storing data to 9-track magnetic tape, NAND flash memory, and rotating media such as floppy disks, hard disks, and optical discs. Most file systems are based on a block device, which is a level of abstraction for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ext3
ext3, or third extended filesystem, is a journaled file system that is commonly used by the Linux kernel. It used to be the default file system for many popular Linux distributions. Stephen Tweedie first revealed that he was working on extending ext2 in ''Journaling the Linux ext2fs Filesystem'' in a 1998 paper, and later in a February 1999 kernel mailing list posting. The filesystem was merged with the mainline Linux kernel in November 2001 from 2.4.15 onward. Its main advantage over ext2 is journaling, which improves reliability and eliminates the need to check the file system after an unclean shutdown. Its successor is ext4. Advantages The performance (speed) of ext3 is less attractive than competing Linux filesystems, such as ext4, JFS, ReiserFS, and XFS, but ext3 has a significant advantage in that it allows in-place upgrades from ext2 without having to back up and restore data. Benchmarks suggest that ext3 also uses less CPU power than ReiserFS and XFS. It is als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marshall Kirk McKusick
Marshall Kirk McKusick (born January 19, 1954) is a computer scientist, known for his extensive work on BSD UNIX, from the 1980s to FreeBSD in the present day. He was president of the USENIX Association from 1990 to 1992 and again from 2002 to 2004, and still serves on the board. He is on the editorial board of ''ACM Queue'' Magazine. He is known to friends and colleagues as "Kirk". McKusick received his B.S. in electrical engineering from Cornell University, and two M.S. degrees (in 1979 and 1980 respectively) and a Ph.D. in computer science from the University of California, Berkeley in 1984. McKusick is openly gay and lives in California with Eric Allman, who has been his domestic partner since graduate school and whom he married in October, 2013. BSD McKusick started with BSD by virtue of the fact that he shared an office at Berkeley with Bill Joy, who spearheaded the beginnings of the BSD system. Some of his largest contributions to BSD have been to the file sys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bill Joy
William Nelson Joy (born November 8, 1954) is an American computer engineer and venture capitalist. He co-founded Sun Microsystems in 1982 along with Scott McNealy, Vinod Khosla, and Andy Bechtolsheim, and served as Chief Scientist and CTO at the company until 2003. He played an integral role in the early development of BSD UNIX while being a graduate student at Berkeley, and he is the original author of the vi text editor. He also wrote the 2000 essay " Why The Future Doesn't Need Us", in which he expressed deep concerns over the development of modern technologies. Joy was elected a member of the National Academy of Engineering (1999) for contributions to operating systems and networking software. Early career Joy was born in the Detroit suburb of Farmington Hills, Michigan, to William Joy, a school vice-principal and counselor, and Ruth Joy. He earned a Bachelor of Science in electrical engineering from the University of Michigan and a Master of Science in electrical eng ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samuel J Leffler
Samuel J Leffler is a computer scientist, known for his extensive work on BSD, from the 1980s to FreeBSD in the present day. Among other projects, he created FlexFAX, LibTIFF, and the FreeBSD Wireless Device Drivers. The ''Design and Implementation'' series of books, which he co-authored, While working for the Computer Systems Research Group (CSRG, UC Berkeley) at University of California, Berkeley, Leffler helped with 4.1 and 4.2 BSD release. He has contributed to almost every aspect of BSD systems, including the networking subsystem. After leaving Computer Systems Research Group, Mr. Leffler also worked at Lucasfilm, Pixar Animation Studios, Silicon Graphics, Alias Research, Softimage 3D, Cinetron Computer Systems and VMware. Later he became an independent consultant on system design. Computer Animation Rendering *'' André and Wally B.'' (1984) texturing/matteing *''Luxo Jr.'' (1986) rendering *''Tin Toy'' (1988) renderman team *''Toy Story ''Toy Story'' is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
