Editing AWK (section)

{{Short description|Text processing programming language}}
{{About|the programming language}}
{{Infobox programming language
| logo = The-AWK-Programming-Language.svg
| logo_size = 200px
| screenshot = Awk-example-usage-gimp.gif
| screenshot_size = 250px
| screenshot caption = Usage of AWK in shell to check matching fields in two files
| name = AWK
| paradigm = [[scripting language|Scripting]], [[procedural programming|procedural]], [[data-driven programming|data-driven]]<ref name=developerworks>{{cite web|url=https://www6.software.ibm.com/developerworks/education/au-gawk/au-gawk-a4.pdf|title=Get started with GAWK: AWK language fundamentals|last=Stutz|first=Michael|date=September 19, 2006|work=developerWorks|publisher=[[IBM]]|access-date=2015-01-29|quote=[AWK is] often called a data-driven language -- the program statements describe the input data to match and process rather than a sequence of program steps|archive-date=2015-04-27|archive-url=https://web.archive.org/web/20150427143548/https://www6.software.ibm.com/developerworks/education/au-gawk/au-gawk-a4.pdf|url-status=live}}</ref>
| year = {{start date and age|1977}}
| latest_release_version = [http://pubs.opengroup.org/onlinepubs/9699919799/utilities/awk.html IEEE Std 1003.1-2008] (POSIX) / 1985
| designer = [[Alfred Aho]], [[Peter J. Weinberger|Peter Weinberger]], and [[Brian Kernighan]]
| typing = none; can handle strings, integers and floating-point numbers; regular expressions
| implementations = awk, GNU Awk, mawk, nawk, MKS AWK, Thompson AWK (compiler), Awka (compiler)
| dialects = ''old awk'' oawk 1977, ''new awk'' nawk 1985, ''GNU Awk'' gawk
| influenced_by = [[C (programming language)|C]], [[sed]], [[SNOBOL]]<ref>{{cite book |title=UNIX Workshop |publisher=Macmillan International Higher Education |author=Andreas J. Pilavakis |year=1989 |pages=196 }}</ref><ref>{{cite book |title=Effective Awk Programming: Universal Text Processing and Pattern Matching |edition=4th |publisher=O'Reilly Media |author=Arnold Robbins |year=2015 |pages=560}}</ref>
| influenced = [[Tcl]], [[AMPL]], [[Perl]]<!--1987-->, [[Korn Shell]] (''ksh93''<!--1993-->, ''dtksh'', ''tksh''), [[Lua]]<!--1993-->
| operating_system = [[Cross-platform]]
| website = 
}}

'''AWK''' ({{IPAc-en|ɔː|k}}<ref name=awkLC.DR/>) is a [[domain-specific language]] designed for text processing and typically used as a [[data extraction]] and reporting tool. Like [[sed]] and [[grep]], it is a [[filter (software)|filter]],<ref name=awkLC.DR>{{cite magazine |magazine=Digital Review |date=May 2, 1988 |page=91 |author=James W. Livingston |title=The Great awk Program is No Birdbrain}}</ref> and it is a standard feature of most [[Unix-like|Unix-like operating systems]].

The AWK language is a [[data-driven programming|data-driven]] [[scripting language]] consisting of a set of actions to be taken against [[Stream (computing)|streams]] of textual data – either run directly on files or used as part of a [[pipeline (Unix)|pipeline]] – for purposes of extracting or transforming text, such as producing formatted reports. The language extensively uses the [[string (computer science)|string]] [[datatype]], [[associative array]]s (that is, arrays indexed by key strings), and [[regular expression]]s. While AWK has a limited intended [[Domain (software engineering)|application domain]] and was especially designed to support [[one-liner program]]s, the language is [[Turing-complete]], and even the early Bell Labs users of AWK often wrote well-structured large AWK programs.<ref>{{cite web
| url         = http://www.faqs.org/docs/artu/ch08s02.html#awk
| title       = Applying Minilanguages
| first       = Eric S.
| last        = Raymond
| author-link  = Eric S. Raymond
| work        = The Art of Unix Programming
| at          = Case Study: awk
| archive-url  = https://web.archive.org/web/20080730063308/http://www.faqs.org/docs/artu/ch08s02.html#awk
| archive-date = July 30, 2008
| access-date  = May 11, 2010
| quote       = The awk action language is Turing-complete, and can read and write files.
}}</ref>

AWK was created at [[Bell Labs]] in the 1970s,<ref>{{cite tech report |url=https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.31.1299 |title=Awk — A Pattern Scanning and Processing Language (Second Edition) |last1=Aho |first1=Alfred V. |author-link1=Alfred Aho |last2=Kernighan |first2=Brian W. |author-link2=Brian Kernighan |last3=Weinberger |first3=Peter J. |author-link3=Peter J. Weinberger |date=September 1, 1978 |publisher=Bell Telephone Laboratories, Inc. |series=Unix Seventh Edition Manual, Volume 2 |access-date=February 1, 2020}}</ref> and its name is derived from the surnames of its authors: [[Alfred Aho]] (author of [[egrep]]), [[Peter J. Weinberger|Peter Weinberger]] (who worked on tiny relational databases), and [[Brian Kernighan]]. The acronym is pronounced the same as the name of the bird species [[auk]], which is illustrated on the cover of ''[[The AWK Programming Language]]''.<ref name="AWK1" />  When written in all lowercase letters, as <code>awk</code>, it refers to the [[Unix]] or [[Plan 9 from Bell Labs|Plan 9]] program that runs scripts written in the AWK programming language.