Search for: "pattern"

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action
== Default action == If a [[rule]] does not include an [[action]], then the default action is used. . . . is to output all [[line]]s that matches the [[pattern]]: . . .
1K - last updated 2011-05-09 22:08 UTC by markhobley

AllAboutGetline
//Editor's notes: The article was originally posted on the comp.lang.awk newsgroup, and can still be . . . is non-zero: i) Print the Nth record after some pattern: {{{ sh awk 'c&&!--c;/pattern/{c=N}' . . . every record except the Nth record after some pattern: {{{ sh awk 'c&&!--c{next}/pattern/{c=N}' . . . file }}} iii) Print the N records after some pattern: {{{ sh awk 'c&&c--;/pattern/{c=N}' . . . every record except the N records after some pattern: {{{ sh awk 'c&&c--{next}/pattern/{c=N}' . . .
16K - last updated 2009-02-15 22:14 UTC by waldner

awk1page
an awk program is a series of //pattern { actions }// statements;\\ ie if the input line matchs pattern . . . field. $1 ~ /awk/ { print $0; } }}} An omited pattern matchs every line and an omitted action just . . . prints the line.\\ The special pattern ''END'' is done after all data is read; so . . .
2K - last updated 2012-03-18 22:22 UTC by g0pher

AwkGuide
** Work in Progress ** {{{ import from Mark Hobley's wiki }}} <toc> ---- == Overview * [[Overview]] . . . [[operator]]s * [[output]] * [[parentheses]] * [[pattern]]s * [[precedence]] * [[print]] * [[printf]] . . . * [[return]] * [[RS]] * [[rule]]s * [[search pattern]]s * [[special variable]]s * [[statement]]s . . .
4K - last updated 2011-08-14 15:57 UTC by markhobley

AwkTips
<toc> ---- == Be idiomatic! In this paragraph, we give some hints on how to write more idiomatic . . . to print all the lines in a file that match some pattern (a kind of awk-grep, if you like). A reasonable . . . is usually something like {{{ awk '{if ($0 ~ /pattern/) print $0}' }}} That works, but there are . . . the action are very clear here: {{{ awk '$0 ~ /pattern/ {print $0}' }}} Our next step in the perfect . . . awk-ification of this program is to note that **/pattern/** is the same as **$0 ~ /pattern/**. That . . .
31K - last updated 2009-03-24 16:54 UTC by waldner

Backref2
The usual (and correct) answer for backreferences in awk (for example, the answer you can get on #awk . . . only partly true. If you need to //**match**// a pattern using a regular expression with backreferences, . . .
2K - last updated 2009-03-26 20:24 UTC by waldner

Backreferences
The usual (and correct) answer for backreferences in awk (for example, the answer you can get on #awk . . . only partly true. If you need to //**match**// a pattern using a regular expression with backreferences, . . . like sed's match number specification in the s/pattern/replacement/ command: it can either be a number, . . .
3K - last updated 2010-12-30 06:53 UTC by ppp089210039107.dsl.hol.gr

BeforeAfterMatch
Problem: print the Nth record before or after a certain regular expression matches or, alternativley, . . . match" part: i) Print the Nth record after some pattern: {{{ sh awk 'c&&!--c;/pattern/{c=N}' . . . every record except the Nth record after some pattern: {{{ sh awk 'c&&!--c{next}/pattern/{c=N}' . . . file }}} iii) Print the N records after some pattern: {{{ sh awk 'c&&c--;/pattern/{c=N}' . . . every record except the N records after some pattern: {{{ sh awk 'c&&c--{next}/pattern/{c=N}' . . .
3K - last updated 2009-02-28 20:38 UTC by waldner

brace
== Enclosure of actions == In [[awk]], squiggly braces are used as [[enclosure]]s around [[action]]s . . . to separate them from the [[pattern]]s within the [[rule]]s: == Grouping of statements . . .
1K - last updated 2010-11-10 22:41 UTC by markhobley

case sensitivity
== Indentifier names == The [[awk]] interpreter is lettercase sensitive. This means that [[variable name]]s . . . named %s, %s and %s.\n", dog, Dog, DOG } }}} == Pattern matching == Because [[awk]] is lettercase sensitive, . . . [[pattern]] matching will only occur if the lettercase . . . of the text matches that used in the [[pattern]]. === Performing case insensitive matching . . .
1K - last updated 2011-06-25 05:14 UTC by pgas

ContextGrep
The following snippets print matching lines with surrounding context lines, like GNU grep's **grep -A . . . The following expects two variables to be set: **Pattern** (a regex to match), and **After** (the number . . . lines to print after each match). {{{ awk $0 ~ Pattern { # if we found the pattern ... if (seen++ . . . a oneliner (3 lines of context, with "Regex" as pattern): {{{ awk awk -v N=3 '/Regex/{if (seen++ && . . . (this time, the script expects the variables **Pattern** and **Before** (number of lines before) to . . .
3K - last updated 2011-07-01 08:32 UTC by pgas

FindAllMatches
This bit of code will match all non-overlapping instances of a given pattern in a string and will store . . . in the given array. It returns the number of patterns found. This duplicates some of the functionality . . .
2K - last updated 2009-03-24 09:46 UTC by waldner

GeneralizedTextReplacement
Some times people need to recode in awk something they were previously doing with sed or another tool. . . . how to emulate sed with awk (specifically, the s/pattern/replacement/ command), establishing a basic . . . So, the only sed command worth discussing is s/pattern/replacement/, because everything else you can . . . only, say, the 3rd and 7th occurrence of a pattern, or do some complex operations - including . . . in the original text (the lhs of the s/pattern/replacement/ command in sed), loop over them . . .
6K - last updated 2009-03-26 20:38 UTC by waldner

HomePage
This wiki is maintained by regulars from the **#awk** channel on **[[https://libera.chat/|irc.libera.chat]]** . . . in a string * FindAllMatches of a particular pattern in a string * RepeatAString n times * FormatFileSizes . . .
5K - last updated 2023-06-26 04:15 UTC by HappMacDonald

HomePageJapanese
Here is the Japanese page for [[HomePage]]. 英語のページは[[HomePage|こちら]]です。 この wiki は **[[http://www.freenode.net|irc.freenode.net]]** . . . the history and continuing popularity of his pattern matching language." (「AWK の権威である Alfred V. . . . の "awk: pattern scanning and processing language - Commands . . .
5K - last updated 2008-10-19 07:34 UTC by hi saito

Inicio
Este wiki es mantenido por los usuarios del cenal **#awk** en **[[http://www.freenode.net|irc.freenode.net]]**. . . . the history and continuing popularity of his pattern matching language." (Naomi Hamilton, in Computerworld; . . . - "awk: pattern scanning and processing language - Commands . . . in a string * FindAllMatches of a particular pattern in a string * RepeatAString n times * FormatFileSizes . . .
7K - last updated 2009-02-12 23:31 UTC by fcr

input
The [[awk]] utility can take its input from [[standard input]] or from [[file]]s. If no input files are . . . in the order provided and performs its [[pattern matching]] cycle until all lines of input have . . .
2K - last updated 2011-05-19 22:40 UTC by markhobley

line orientated
== The awk extraction and reporting language is line orientated == The [[awk]] extraction and reporting . . . [[rule]] must begin on the same line as the [[pattern]]. However, it is possible to have the [[pattern]] . . .
1K - last updated 2011-05-17 23:24 UTC by markhobley

LinksPage
<toc> ---- == websites dedicated to awk == * [[http://awk.info/|awk.info]] news and articles about . . . - "awk: pattern scanning and processing language - Commands . . . the history and continuing popularity of his pattern matching language." (Naomi Hamilton, in Computerworld; . . .
4K - last updated 2015-02-24 14:45 UTC by pgas

Overview
= Overview of awk = == The primarily purpose of awk is to processing textual data to produce formatted . . . == The awk utility performs a cycle of pattern matching and performing associated actions . . . [[line]] of [[input]] and compares with each [[pattern]] in the [[script]]. If a [[pattern]] matches . . . takes the [[action]] associated with the [[pattern]]. If the line does not match the [[pattern]], . . . utility takes no action. If more than one [[pattern]] matches the [[input file]], then the [[action]] . . .
4K - last updated 2011-05-23 23:09 UTC by markhobley

Overview of regular expressions
== What is a regular expression? == A regular expression is a method of representing a string matching . . . pattern. Regular expressions enable strings that match . . . a particular pattern within textual data records to be located and . . . [[anchor]]s used to specify the position of the pattern in relation to a line of text. * [[character . . .
2K - last updated 2011-05-17 20:32 UTC by markhobley

PassingAShellVariable
The common solution is to use the -v option to define an awk variable giving it the value of the shell . . . 'BEGIN{print awkvar}' }}} If you want to pass a pattern as a variable take care that the pattern is . . . awk '/foo\./{print}' #version with a variable pattern='foo\\.' awk -v pattern="$pattern" '$0 ~ pattern{print}' . . .
1K - last updated 2009-01-30 08:36 UTC by pgas

pattern
In [[awk]], patterns are used to select lines of input for processing. The pattern within each [[rule]] . . . The [[action]] only executes if its relevant pattern was matched or the pattern was omitted from . . . the [[rule]]. === Regular Expression Patterns === A pattern may contain [[regular expression]]s . . . for [[regular expression]]s used in the pattern. In the following example, the [[action]] (to . . . {{{ /foobar/ {print $0} }}} === Start and End Patterns === It is possible to create a pattern consisting . . .
2K - last updated 2011-05-19 18:18 UTC by markhobley

print
== Usage == === print [ LIST ] === The [[variadic]] **print** function is used to produce simple standardized . . . is to print all [[line]]s that match the [[pattern]]. This means that an [[action]] to just print . . .
1K - last updated 2011-05-11 15:10 UTC by markhobley

qse
Not a standalone awk, but an interesting library embedding an awk interpreter, from [[https://groups.google.com/group/comp.lang.awk/browse_thread/thread/b02c0d75e49eab75/54fc2c6316d657bc?lnk=gst&q=c%2B%2B+embed#54fc2c6316d657bc| . . . script * open a new runtime context * execute pattern-action blocks or call a function * close the . . . retv = qse_awk_rtx_loop (rtx); /* exeucte pattern-action blocks */ if (!retv) FAIL (qse_awk_rtx_geterrmsg(rtx)); . . . == QSE_NULL) FAIL (awk); // execute the BEGIN, pattern-action, END blocks. MyAwk::Value r; if (awk.loop . . .
4K - last updated 2011-10-27 06:25 UTC by pgas

regular expression operator
The [[awk]] programming language provides a set of *regular expression operators* that have special meanings . . . required when a regular expression is used as a pattern within a rule_ A binding operator is not required . . . if a regular expression is being used as a pattern within a rule: {{{ # There is no binding operator . . . when a regular expression is used as a pattern /rhubarb/ {print $0} }}} === _Substitution . . .
2K - last updated 2013-02-19 14:06 UTC by markhobley

rule
Scripts in [[awk]] may contain one or more rules. == Rules consist of patterns and actions == Each rule . . . within an [[awk]] script consists of a [[pattern]] and an associated [[action]]. The [[pattern]] . . . in squiggly [[brace]]s to separate it from the pattern: == Patterns or actions can be omitted from . . . a rule == The [[pattern]] or the [[action]] can be omitted from an . . . rule, but it is not possible for both the [[pattern]] and the [[action]] to omitted. === Omission . . .
1K - last updated 2011-05-11 15:07 UTC by markhobley

SedFAQ
<toc> ---- == I have a line like "abdcgfjeuPATTERNfjfhghj", I want to get the PATTERN part, why . . . isn't sed 's/\(PATTERN\)/\1/' working? I get the input line unchanged! . . . only the 123? No, right? Now, to extract your PATTERN, you are using code that produces an equivalent . . . not work. It just replaces, within the line, PATTERN with itself. Then, sed prints what's in the . . . pattern space, which is still the whole line. See the . . .
34K - last updated 2010-02-14 17:56 UTC by waldner

slash
== Division Operator == The slash symbol is used as the division operator to produce the [[result]]s . . . that marks a [[regular expression]] as a [[pattern]]: {{{ # foobar is a regular expression used . . . as a pattern /foobar/ { print $0 } }}} . . .
1K - last updated 2011-05-11 15:00 UTC by markhobley

tilde
== Substring containment operator == The tilde [[symbol]] can be used as a containment operator providing . . . a [[pattern]] match if a string matches a [[regular expression]]: . . .
1K - last updated 2011-05-19 19:04 UTC by markhobley

VariablesInRegex
The patterns between slashes like /pattern/ are called **ERE constants**, or **regular expressions literals**. . . .
2K - last updated 2010-11-26 08:49 UTC by 195.97.26.99

WartAndWishList
Awk is a wonderful language! That said, there are a few annoying bits... == The Good * well-documented . . . ordering of arguments to the {{{match(string, pattern)}}} built-in function is jarring. The gawk . . . remember if one thinks of it as the {{{string ~ pattern}}} matching operator, but it is backward from . . .
7K - last updated 2009-04-13 18:39 UTC by goedel

32 pages found.