Other uses AT disambiguation lowercase In Unix like computer operating system s, the code at code command is used to schedule command computing command s to be executed once, at a particular system time time in the future. More precisely, it reads a series of commands from standard input and collects them into one at job which is carried out at a later date. The at job inherits the current environment, so that it is executed in the same working directory and with the same environment variable s set as when it was scheduled. It differs from code cron code which is used for recurring executions e.g. once an hour, every Tuesday, January 1 every year . As with code cron code , many Unix systems allow the administrator to restrict access to the code at code command. code at code can be made to mail a user when done carrying out a scheduled job of theirs, can use more than one job queue, and can read a list of jobs to carry out from a file instead of standard input. A sample command to compile a C programming language C program at 11 45 a. m. on January 31st and e mail the results Standard streams STDOUT and STDERR to your user ID would be source lang bash echo cc o foo foo.c at 1145 at 1145 jan 31 at cc o foo foo.c at D press Control D while at the beginning of a line atq 1234 2011 08 12 11 45 cc o foo foo.c user atrm 1234 atq source In some Unix like computer operating system s it uses a Daemon computer software daemon , code atd code , which waits in the background periodically checking .... Launchd Apple Computer s replacement for at. List of Unix programs External links man cu at SUS execute commands at a later time man 1 at queue, examine or delete jobs for later execution unix commands unix stub Category Standard Unix programs At Category Unix SUS2008 utilities Category Unix process and task management related software ca At Unix cs At Unix de At Unix el At Unix es At Unix fr At Unix it At Unix hu At Unix ja At UNIX pl At Unix pt At Unix ro At Unix ru At uk At ... more details
notability date September 2011 Unreferenced stub auto yes date December 2009 Expert subject Telecommunications date November 2008 infobox software name As latest release version latest release date platform website as is a generic name for an assembly language Assembler assembler on Unix . The GNU Project s assembler is named GNU assembler Gas . Category Assemblers Category Unix programming tools Unix stub ru As ... more details
Infobox OS name Unix logo screenshot Image Unix history simple.svg 250px caption Evolution of Unix and Unix ... model Historically Closed source software closed source , now some Unix projects Berkeley Software ... Command line interface & Graphical user interface Graphical X Window System family Unix released 1969 ... language English license Proprietary software Proprietary working state Active Unix officially trademarked as UNIX , sometimes also written as span style font variant small caps Unix span is a Computer ... . The Unix operating system was first developed in assembly language , but by 1973 had been almost ... portability porting to other hardware. Today s Unix system evolution is split into various branches ... consortium, owns the UNIX trademark. Only systems fully compliant with and certified according to the Single UNIX Specification are qualified to use the trademark others might be called Unix system like or Unix like , although the Open Group disapproves ref http www.unix.org questions answers faq.html 7a What is a Unix like operating system? Unix.org FAQ ref of this term. However, the term Unix .... During the late 1970s and early 1980s, the influence of Unix in academic circles led to large scale adoption of Unix particularly of the Berkeley Software Distribution BSD variant, originating ... Operating System Solaris , HP UX and AIX operating system AIX . Among all variants of Unix, Mac ... devices such as routers. Today, in addition to certified Unix systems such as those already mentioned, Unix like operating systems such as MINIX , Linux , Android operating system Android , and BSD ... Unix may be used to describe a Unix or an operating system that has the characteristics of either Version 7 Unix or UNIX System V . Overview Unix operating systems are widely used in Server computing ... 2010 09 29 unixs revenge title Unix s Revenge publisher asymco date 2010 09 29 accessdate 2010 11 09 ref The Unix environment and the client server program model were essential elements in the development ... more details
lowercase Image Pg Unix screenshot.png thumbnail Example output of the tt pg tt command in xterm . pg is a terminal pager program on Unix and Unix like systems for viewing text file s. It can also be used to page through the output of a command via a pipe Unix pipe . pg uses an interface similar to vi , but commands are different. ref http www.computerhope.com unix upg.htm Linux Unix pg command ref more command more , and less Unix less are more commonly used paging programs. See also less Unix less more command more References reflist Unix commands unix stub Category Terminal pagers ... more details
lowercase Unreferenced date March 2007 The tt install tt command is a standard Unix program used to copy Computer file files and set file permissions . Category Standard Unix programs Unix stub ... more details
Unreferenced date December 2009 In Unix and Unix like operating systems, a filter is a program that gets most of its data from its standard input the main input stream and writes its main results to its standard output the main output stream . Unix filters are often used as elements of pipeline Unix pipeline s. The pipe operator on a command line signifies that the main output of the command to the left is passed as main input to the command on the right. The classic filter would be grep , which at it simplest prints to its output any lines containing a character string. Here s an example cut d f 1 etc passwd grep foo This finds all registered users that have foo as part of their username by using the Cut Unix cut command to take the first field username of each line of the Unix system password file and passing them all as input to grep, which searches its input for lines containing the character string foo and prints them on its output. Here is a Perl equivalent to the above, which prints the whole line from the passwd file perl ne print if m foo etc passwd Or, to print only the username, without the rest of the line perl ane shift F print n if foo F etc passwd Common Unix filter programs are Cat Unix cat , cut Unix cut , grep , head Unix head , Sort Unix sort , uniq and tail Unix tail . Programs like awk and sed can be used to build quite complex filters because they are fully programmable. List of Unix filter programs awk programming language awk cat Unix cat comm Unix comm cut Unix cut Expand Unix expand compress Fold Unix fold grep head Unix head Nl Unix nl perl Pr Unix pr sed UNIX shell sh Sort Unix sort Split Unix split Strings Unix strings tail Unix tail Tac Unix tac Tee Unix tee tr program tr uniq Wc Unix wc See also Filter software Unix commands Category Unix da Filter program it Filtro Unix ja pt Filtro Unix ... more details
saved book title Unix subtitle cover image Poundexclam.svg cover color Black Unix Introduction UnixUnix wars Historically significant corporations AT&T Bell Labs Hewlett Packard IBM Novell SCO Group Sun Microsystems Unix standards and organizations The Open Group X Open POSIX Single UNIX Specification Unix operating systems Berkeley Software Distribution 1977 Berkeley Software Distribution Version 7 Unix 1979 Version 7 Unix SunOS 1982 SunOS UNIX System V 1983 UNIX System V HP UX 1984 HP UX IBM AIX 1986 AIX IRIX 1988 IRIX SCO OpenServer 1989 SCO OpenServer Solaris operating system 1992 Solaris Tru64 UNIX 1992 Tru64 UNIX UnixWare 1992 UnixWare Mac OS X 2001 Mac OS X Unix like operating environments Unix like Cygwin FreeBSD GNU Interix Linux NetBSD NeXTSTEP OpenBSD OpenSolaris Plan 9 from Bell Labs Legal battles and controversies SCO Linux controversies SCO v. IBM SCO v. Novell SCO and SGI Red Hat v. SCO USL v. BSDi Category Wikipedia books on computing ... more details
lowercase title clear Unix Image Clear gnulinux.gif thumb Clear being used on GNU Linux under uxterm code clear do not subst template code tag breaks popups is a standard Unix computer operating system command which is used to clear the screen. Depending on the system, tt clear tt uses the terminfo or termcap database, as well as looking into the environment for the terminal type in order to deduce how to clear the screen. The Unix command tt clear tt takes no arguments and is roughly analogous to the MS DOS command tt Cls computing cls tt . See also List of Unix programs External links http invisible island.net ncurses man clear.1.html The manual tt man tt page for tt clear tt unix commands Unix stub Category Unix software el Clear Unix fa Clear fr Clear Unix hu Clear Unix ... more details
Ancient UNIX is a term coined by Santa Cruz Operation , Citation needed date October 2009 to describe early releases of the Unix code base released prior to Unix System III , particularly the Research Unix releases prior to and including Version 7 the base for UNIX 32V as well as later developments of AT&T Unix . After the publication of the Lions Commentary on UNIX 6th Edition, with Source Code Lions book , work was undertaken to release the earlier versions of the codebase. SCO first released the code under a limited educational license. Citation needed date October 2009 Later, in January 2002, Caldera International now SCO Group relicensed but has not made available several versions under the four clause BSD license , namely ref cite web url http www.lemis.com grog UNIX title UNIX is free ... February 19, 2009 title Dear Unix enthusiasts, last Broderick first Bill date January 23, 2002 publisher Caldera ref UNIX 32V Research Unix early versions only Version 1 Unix Version 2 Unix Version 3 Unix Version 4 Unix Version 5 Unix Version 6 Unix Version 7 Unix So far there has been no widespread use of the code, but it can be used on emulator systems, and Version 5 Unix has been made to run ... www.kernelthread.com publications gbaunix title UNIX on the Game Boy Advance last Singh first Amit date August 2004 accessdate 2009 10 22 ref As an example of how relicensing the old Unix code bases has affected the modern computing community, the BSD vi text editor was based on code from the ed UNIX ... vi has been adapted for modern Unix like operating systems. ref cite web url http ex vi.sourceforge.net title The Traditional Vi ref References reflist External links http www.tuhs.org The Unix Heritage Society , TUHS a website dedicated to the preservation and maintenance of historical UNIX ... unix 1st Unix First Edition Manual Pages Unix like DEFAULTSORT Ancient Unix Systems Category Bell Labs Unices Category Discontinued operating systems Unix stub ja Ancient UNIX ... more details
Image Unix history simple.svg thumb Diagram of the relationships between the major Unix like systems A Unix like sometimes referred to as UN X or nix operating system is one that behaves in a manner similar to a Unix system, while not necessarily conforming to or being certified to any version of the Single UNIX Specification . There is no Technical standard standard for defining the term, and some difference of opinion is possible as to the degree to which a given OS is Unix like . The term can include free and open source software free and open source operating systems inspired by Bell Labs Unix ... on the software license licensed UNIX source code which may be sufficiently Unix like to pass certification and bear the UNIX trademark . Definition The Open Group owns the UNIX trademark and administers the Single UNIX Specification, with the UNIX name being used as a certification mark . They do not approve of the construction Unix like , and consider it a misuse of their trademark. Their guidelines require UNIX to be presented in uppercase or otherwise distinguished from the surrounding ... The Open Group. ref Other parties frequently treat Unix as a genericized trademark . Some add ... S. Raymond coauthors Guy L. Steele Jr. work The Jargon File ref or nix , since Unix like systems often have Unix like names such as AIX operating system AIX , HP UX , IRIX , Linux , Minix , Ultrix ... to refer to any UNIX descendant or work alike system, even those with completely dissimilar names ... of UNIX as a trademark, but lost his case, and lost again on appeal. Also in 2007, the Open ... Nummer 3, 17 April 2007 ref History Ref improve section date April 2010 Unix like systems ... to academic users of UNIX. When AT&T later allowed commercial licensing of UNIX in the 1980s, a variety ... POSIX and the Single UNIX Specification . Meanwhile, the GNU Project was launched in 1983 with the goal .... Various Unix like operating systems developed alongside GNU, frequently sharing substantial ... more details
Bell Unix Columbus UNIX or CB UNIX was, according to Marc Rochkind , ref cite book last Rochkind first Marc title Advanced UNIX Programming publisher Prentice Hall year 1985 pages 156 157 isbn 0 13 011800 1 ref a variant of the UNIX operating system internal to Bell Labs . It was developed at the Columbus, Ohio Columbus , Ohio branch and was little known outside the company. CB UNIX was developed to address deficiencies inherent in Research Unix , notably the lack of interprocess communication and file locking , considered essential for a database management system . Several Bell System operation support system products were based on CB UNIX such as Switching Control Center System . The primary innovations were power fail restart, line disciplines, terminal types, and IPC features similar to System V s messages and shared memory . ref cite newsgroup title UNIX history author Dale Dejager date 1984 01 16 newsgroup net.unix url http groups.google.com group net.unix msg b80689d4b3bff13f?dmode source ref Image CB Unix Manuals.jpg thumb left 200px Volume 1 and Volume 2 of the UNIX Programmers Manual CB Version References reflist Unix like Unix stub DEFAULTSORT Cb Unix Category Bell Labs Unices Category Discontinued operating systems ... more details
lowercase fg is a job control Unix job control command in Unix and Unix like operating systems that resumes execution of a suspended Process computing process by bringing it to the foreground and thus redirecting its standard input and standard output output streams to the user s computer terminal terminal . ref name man http www.computerhope.com unix ufg.htm fg man page ref fg is required to be included in an operating system in order for it to be POSIX compliant. ref name POSIX commands http manuals.fujitsu siemens.com servers bs2 man man us posix v6 0 posix k.pdf POSIX BS2000 OSD Commands User Guide ref See also bg Unix bg , the complementary command that sends a process to the background SIGCONT References Reflist External links man cu fg SUS run jobs in the foreground Unix commands Category Standard Unix programs Category Unix SUS2008 utilities Unix stub ca Fg Unix el Fg Unix fr Fg Unix pl Fg Unix ... more details
Multiple issues unreferenced February 2007 orphan February 2009 Infobox OS name Unix NS screenshot caption developer NCR Corporation NCR family Unix source model Closed source kernel type Monolithic kernel license Proprietary software Proprietary Unix NS the NCR Corporation NCR 3700 Operating System is based on the Unix SVR4 . It contains significant extensions for massively parallel systems, in particular Distributed Memory DBMSs. The extensions include the concepts of virtual processor and virtual disk, message and global synchronization system, segment system, and globally distributed objects. When compared to other parallel UNIX operating systems like Mach or ChorusOS Chorus , Unix NS has a more powerful communication and message addressing paradigm, and richer process group management and global synchronization mechanism. Unix like DEFAULTSORT Unix Ns Category System V de Unix NS ... more details
The Unix System ISBN 0 201 13791 7 is a book by Stephen R. Bourne it was the first widely available general introduction to the Unix operating system . It included some historical material on Unix, as well as material on using the system, editing, the software tools concept, C programming using the Unix API , data management with the shell and awk , and typesetting with troff . DEFAULTSORT Unix System Category Computer books compu book stub ... more details
lowercase bg is a job control Unix job control command in Unix and Unix like operating systems that resumes execution of a suspended Process computing process without bringing it to the foreground ref name bg man page http pwet.fr man linux commandes posix bg bg man page ref the resumed process continues to execute in the background without receiving user input from the Computer terminal terminal . bg is required to be included in an operating system in order for it to be POSIX compliant. ref name POSIX commands http manuals.fujitsu siemens.com servers bs2 man man us posix v6 0 posix k.pdf POSIX BS2000 OSD Commands User Guide ref See also fg Unix fg , the complementary command that brings a process to the foreground References Reflist Unix commands Category Standard Unix programs Category Unix SUS2008 utilities unix stub ca Bg Unix el Bg Unix fr Bg Unix zh Bg Unix ... more details
lowercase code fc do not subst template code tag breaks popups is a standard program on Unix that lists or edits and reexecutes, commands previously entered to an interactive shell. fc is a Shell builtin built in command in the Bash Unix shell bash shell help fc will show usage information. Examples Features History See also List of Unix programs References Solaris 10 man page for fc command External links man cu fc SUS process the command history list unix commands Category Standard Unix programs Category Unix SUS2008 utilities el Fc ... more details
lowercase head is a Computer program program on Unix and Unix like systems used to display the first few lines of a text Computer file file or pipe computing pipe d data. The command syntax is head options < file name> By default, tt head tt will print the first 10 lines of its input to the standard output . The number of lines printed may be changed with a command line option. The following example shows the first 20 lines of filename head n 20 filename This displays the first 5 lines of all files starting with foo head n 5 foo Some versions omit the n and just let you say 5. Flags c x number of bytes Copy first x number of bytes. Other Many early versions of Unix did not have this command, and so documentation and books had sed do this job sed 5q foo This says to print every line implicit , and quit after the fifth. See also tail Unix tail , dd Unix dd List of Unix programs External links http www.gnu.org software coreutils manual html node head invocation.html head manual page from GNU coreutils . http www.freebsd.org cgi man.cgi?query head&apropos 0&sektion 0&manpath FreeBSD 5.3 RELEASE and Ports&format html FreeBSD documentation for head Unix commands Category Unix text processing utilities Category Unix SUS2008 utilities cs Head de Head Unix el Head Unix es Head Unix fr Head Unix ko Head it Head hu Head Unix ja Head pl Head Unix pt Head ro Head Unix ru Head Unix uk Head tr Head Unix ... more details
Orphan date February 2009 lowercase timex is a Unix utility tool, most commonly used in the measurement of duration of shell processes. It is also used to measure process data and system activity. The tool appears in IBM s AIX operating system AIX version of Unix and the Solaris Operating System from Sun Microsystems. See also List of Unix programs External links http www.llnl.gov computing tutorials performance tools man timex.txt Lawrence Livermore National Laboratory s copy of the AIX timex man page. http docs.sun.com app docs doc 816 5165 timex 1?l en&a view&q timex timex time a command report process data and system activity Solaris Operating System Solaris Manual page Unix man page unix commands Category Unix process and task management related software unix stub pl Timex Unix ... more details
lowercase tac is a Linux command that allows you to see a file line by line backwards. It is named by analogy with cat Unix cat . Its standard Unix equivalent is code tail r code . Usage pre Usage tac OPTION ... FILE ... Write each FILE to standard output, last line first. With no FILE, or when FILE is , read standard input. Mandatory arguments to long options are mandatory for short options too. b, before attach the separator before instead of after r, regex interpret the separator as a regular expression s, separator STRING use STRING as the separator instead of newline help display this help and exit version output version information and exit pre See also cat Unix cat External links Manual pages man 1 tac unix commands Category Unix text processing utilities Unix stub hu Tac Unix pl Tac Unix ru Tac uk Tac ... more details
lowercase type Unix type is a Unix command that describes how its arguments would be interpreted if used as command names. Function Where applicable, type will display the command name s path. Possible command types are Shell builtin shell built in function alias command alias hashed command keyword The command returns a non zero exit status if command names cannot be found. Examples type test test is a shell builtin type cp cp is bin cp type unknown bash type unknown not found type type type is a shell builtin See also List of Unix utilities command shell builtin which Unix hash Unix Category Standard Unix programs Category Unix SUS2008 utilities software stub unix commands ... more details
Refimprove date December 2009 Image Unix history.svg thumb 450px Unix genealogy tree The Unix wars were the struggles between vendor s of the Unix computer operating system in the late 1980s and early 1990s to set the standard for Unix thenceforth. Origins In the mid 1980s, the two common versions of Unix were BSD , from the University of California, Berkeley , and UNIX System V System V , from AT&T . Both were derived from the earlier Version 7 Unix , but had diverged considerably. Further, each vendor s version of Unix was different to some degree. A group of vendors formed the X Open open standard ... s. They chose to base their system on Unix. X Open caught AT&T s attention. To increase the uniformity of Unix, AT&T and leading BSD Unix vendor Sun Microsystems started work in 1987 on a unified system ... Laboratory s System V environment for BSD Unix. This was eventually released as System V Release 4 SVR4 . While this decision was applauded by customers and the trade press, certain other Unix licensees .... The same year, AT&T and another group of licensees responded by forming UNIX International . Technical ... versions of Unix, with X Open holding the middle ground. The move towards open source code In March ..., effectively marking the end of the most significant era of the Unix wars. In June, AT&T sold its UNIX assets to Novell , and in October Novell transferred the Unix brand to X Open. In 1996, X Open and the new OSF merged to form the Open Group . COSE work such as the Single UNIX Specification , the current standard for branded Unix, is now the responsibility of the Open Group. However, the damage to Unix s market reputation had been done. Since then, occasional bursts of Unix factionalism have broken ... Caldera . The Berkeley Software Distribution emerged as an independent Unix like operating system, with the purging ... based on this combination. Linux derivatives are not compatible enough to qualify for the Unix trademark. On the other hand, BSD systems can at least claim direct ancestry to Version 7 Unix . Or, according ... more details
Inappropriate tone date December 2007 Bell Unix Research Unix is a term used to refer to versions of the Unix ... to as Department 1127 . History The term Research Unix first appeared in the Bell System Technical ... Labs such as PWB UNIX and Multi Environment Real Time MERT whose code base had diverged from the primary CSRC version. However, that term was little used until Version 8 Unix , but has been retcon retroactively ... called simply UNIX in caps or the UNIX Time Sharing System. Because both the early versions and the last ... Unix versions are often referred to by the edition of the Unix manual manual that describes them. So, the first Research Unix would be the First Edition, and the last the Tenth Edition. Another common way of referring to them is Version x or V x Unix, where x is the manual edition. All modern editions of Unix excepting implementations from scratch like Coherent operating system Coherent , Minix , and Linux , usually referred to as Unix like derive from the 7th Edition. Versions class wikitable Manual Edition Release date Description 1st Edition Nov. 3, 1971 First edition of the Unix manual, based on the version that ran on the PDP 11 at the time. Unix was actually 2 years old at the time and had ... the C programming language C programming language and Unix pipe pipes total number of installations was 16. 4th Edition Nov. 1973 First Unix written in C programming language C . It also introduced Group identifier Unix groups . Number of installations was listed as above 20 . The manual was formatted ... above 50 . Version 6 Unix 6th Edition May 1975 First Unix to see widespread distribution outside ... UNIX, a cut down v6 for the low end PDP 11 10. Version 7 Unix 7th Edition Jan. 1979 The ancestor of all modern UNIX systems and the last release of Research Unix to see widespread external distributions. Merged together most of the utilities of PWB UNIX with an extensively modified kernel with almost 80 more lines of code than V6. In February, a port called UNIX 32V 32V was made to DEC s VAX hardware ... more details
Other uses Strip disambiguation unreferenced date July 2011 lowercase title strip Unix In Unix and Unix like operating systems, the tt strip tt program removes unnecessary information from executable binary programs and object files, thus potentially resulting in better performance and sometimes significantly less disk space usage. This information may consist of debugging and symbol information however the standard leaves the scope of changes up to the implementer. The GNU Project ships an implementation of tt strip tt as part of the GNU Binutils package. tt strip tt has been ported to other operating systems including Microsoft Windows . Example strip foobar See also Portal Free software Executable compression List of Unix programs tt Strings Unix strings tt Debug symbol Symbol table References citation publisher The Open Group url http www.opengroup.org onlinepubs 007908799 xcu strip.html contribution strip title The Single UNIX Specification, Version 2 date 1997 External links man 1 strip Discard symbols from object files Unix commands Category Unix programming tools Category Unix SUS2008 utilities Unix stub el Strip Unix ko Strip ... more details
Unix International or UI was an association created in 1988 to promote open standards, especially the Unix operating system . Its most notable members were AT&T and Sun Microsystems , and in fact the commonly accepted reason for its existence was as a counterbalance to the Open Software Foundation OSF , itself created in response to AT&T s and Sun s Unix partnership of that time. UI and OSF thus represented the two sides of the Unix Wars in the late 1980s and early 1990s. In May 1993, the major members of both UI and OSF announced the Common Open Software Environment COSE initiative. This was followed by the merging of UI and OSF into a new OSF in March 1994, which in turn merged with X Open in 1996, forming The Open Group . References http www.groklaw.net article.php?story 20050601125916588 Chapter 11. OSF and UNIX International Peter H. Salus , The Daemon, the GNU and the Penguin http groups.google.com group comp.unix.osf.misc msg 4ebc895ff10823f1 UI OSF merger announcements org stub Category Standards organizations Category Unix history cs Unix International es Unix International ko ja UNIX International pt Unix International ru Unix International ... more details
lowercase In computer software , tt id tt is a program in Unix like operating system s that prints the User identifier Unix user or Group identifier Unix group identifier of the account by which the program is executed an example of the command tt id tt as executed by user tt alice tt source lang bash alice darkstar id uid 1016 alice gid 100 users groups 100 users source The superuser root account has a UID of 0 source lang bash root darkstar id uid 0 root gid 0 root groups 0 root source The tt whoami tt utility has been obsoleted by the tt id tt utility and displays a user s ID as a name source lang bash alice darkstar whoami alice alice darkstar id un Where u refers to user and n refers to name alice source See also List of Unix programs User identifier Unix UID Group identifier Unix GID tt Who Unix who tt tt uname tt References man cu id SUS return user identity Unix commands Category Unix user management and support related utilities Category Unix SUS2008 utilities cs Id Unix el Id Unix fr Id Unix hu Id Unix ja Id UNIX pl Id Unix pt Id Unix ru Id uk Id ... more details
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