In Unix and operating systems inspired by it, the file system is considered a central component of the operating system. It was also one of the first parts of the system to be designed and implemented by Ken Thompson in the first experimental version of Unix, dated 1969 .
16-651: [REDACTED] Look up usr in Wiktionary, the free dictionary. USR may refer to: USRobotics , a technology firm USR (Guadeloupe football club) , in Sainte-Rose, Guadeloupe U.S. Robots and Mechanical Men , a fictional robot manufacturer /usr, directory in Unix systems, see Filesystem Hierarchy Standard A variant of the Steyr AUG , assault rifle Save Romania Union ,
32-775: A Romanian political party Union of Serbs of Romania , a Romanian political party USR (BASIC) ("User Serviceable Routine"), a common BASIC instruction to execute native machine code Upward Sun River site , archaeological site in Alaska Uxbridge and South Ruislip , a parliamentary constituency in the United Kingdom Unión Santafesina de Rugby , body that rules the game of rugby union in Santa Fe, Argentina See also [ edit ] μSR, Muon Spin Rotation or muon spin spectroscopy Topics referred to by
48-713: A Unix operating system: Research Unix Research Unix are early versions of the Unix operating system for DEC PDP-7 , PDP-11 , VAX and Interdata 7/32 and 8/32 computers, developed in the Bell Labs Computing Sciences Research Center (CSRC). The term Research Unix first appeared in the Bell System Technical Journal (Vol. 57, No. 6, Part 2 July/August 1978) to distinguish it from other versions internal to Bell Labs (such as PWB/UNIX and MERT ) whose code-base had diverged from
64-435: A bit more BSD-flavored than SysVish, but it was pretty eclectic. In 2002, Caldera International released Unix V1, V2, V3, V4, V5, V6 , V7 on PDP-11 and Unix 32V on VAX as FOSS under a permissive BSD-like software license . In 2017, Unix Heritage Society and Alcatel-Lucent USA Inc., on behalf of itself and Nokia Bell Laboratories , released V8, V9, and V10 under the condition that only non-commercial use
80-431: A drive letter that denotes the root of its file system tree), such volumes can be mounted on a directory, causing the volume's file system tree to appear as that directory in the larger tree. The root of the entire tree is denoted / . In the original Bell Labs Unix , a two-disk setup was customary, where the first disk contained startup programs, while the second contained users' files and programs. This second disk
96-468: A file type to be used for interprocess communication : BSD added sockets , while System V added FIFO files . BSD also added symbolic links (often termed "symlinks") to the range of file types, which are files that refer to other files, and complement hard links. Symlinks were modeled after a similar feature in Multics , and differ from hard links in that they may span filesystems and that their existence
112-461: Is different from Wikidata All article disambiguation pages All disambiguation pages usr As in other operating systems, the filesystem provides information storage and retrieval, and one of several forms of interprocess communication , in that the many small programs that traditionally form a Unix system can store information in files so that other programs can read them, although pipes complemented it in this role starting with
128-419: Is independent of the target object. Other Unix systems may support additional types of files. Certain conventions exist for locating some kinds of files, such as programs, system configuration files, and users' home directories . These were first documented in the hier(7) man page since Version 7 Unix ; subsequent versions, derivatives and clones typically have a similar man page. The details of
144-713: Is the manual edition. All modern editions of Unix—excepting Unix-like implementations such as Coherent , Minix , and Linux —derive from the 7th Edition. Starting with the 8th Edition, versions of Research Unix had a close relationship to BSD . This began by using 4.1cBSD as the basis for the 8th Edition. In a Usenet post from 2000, Dennis Ritchie described these later versions of Research Unix as being closer to BSD than they were to UNIX System V , which also included some BSD code: Research Unix 8th Edition started from (I think) BSD 4.1c, but with enormous amounts scooped out and replaced by our own stuff. This continued with 9th and 10th. The ordinary user command-set was, I guess,
160-646: The Third Edition . Also, the filesystem provides access to other resources through so-called device files that are entry points to terminals , printers , and mice . The rest of this article uses Unix as a generic name to refer to both the original Unix operating system and its many workalikes . The filesystem appears as one rooted tree of directories. Instead of addressing separate volumes such as disk partitions , removable media, and network shares as separate trees (as done in DOS and Windows : each drive has
176-715: The directory layout have varied over time. Although the file system layout is not part of the Single UNIX Specification , several attempts exist to standardize (parts of) it, such as the System V Application Binary Interface , the Intel Binary Compatibility Standard , the Common Operating System Environment, and Linux Foundation 's Filesystem Hierarchy Standard (FHS). Here is a generalized overview of common locations of files on
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#1732848533358192-656: The file system may refer to the same file, a feature termed a hard link . The mathematical traits of hard links make the file system a limited type of directed acyclic graph , although the directories still form a tree, as they typically may not be hard-linked. (As originally envisioned in 1969, the Unix file system would in fact be used as a general graph with hard links to directories providing navigation, instead of path names. ) The original Unix file system supported three types of files: ordinary files, directories , and "special files", also termed device files. The Berkeley Software Distribution (BSD) and System V each added
208-518: The primary CSRC version. However, that term was little-used until Version 8 Unix , but has been retroactively applied to earlier versions as well. Prior to V8, the operating system was most commonly called simply UNIX (in caps) or the UNIX Time-Sharing System. AT&T licensed Version 5 to educational institutions, and Version 6 also to commercial sites. Schools paid $ 200 and others $ 20,000, discouraging most commercial use, but Version 6
224-403: The same term [REDACTED] This disambiguation page lists articles associated with the title USR . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=USR&oldid=1222880690 " Category : Disambiguation pages Hidden categories: Short description
240-437: Was mounted at the empty directory named usr on the first disk, causing the two disks to appear as one filesystem, with the second disk’s contents viewable at /usr . Unix directories do not contain files. Instead, they contain the names of files paired with references to so-called inodes , which in turn contain both the file and its metadata (owner, permissions, time of last access, etc., but no name). Multiple names in
256-551: Was the most widely used version into the 1980s. Research Unix versions are often referred to by the edition of the manual that describes them, because early versions and the last few were never officially released outside of Bell Labs, and grew organically. So, the first Research Unix would be the First Edition, and the last the Tenth Edition. Another common way of referring to them is as "Version x Unix" or "V x Unix", where x
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