AwkChannelWiki: Search for: "character"

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Adler32Checksum
As documented in the [[http://en.wikipedia.org/wiki/Adler-32 | Adler-32 Wikipedia article]]. {{{ awk . . . 'ord' array. If we query for some # random character and it's not in the array, we reinitialize . . . on null strings? Strings with international characters? Strings with binary data? Strings with . . . embedded NUL characters?), and no testing has been done to compare . . .
4K - last updated 2008-12-31 12:05 UTC by pgas

awk nawk oawk
in 1977 there was awk.\\ this page attempts to explain the history of awk.\\ the 1978 7th Edition awk(1) . . . line: -v x=1 -v y=2\\ CONVFMT\\ nextfile\\ posix character class names like [:digit:]\\ length(arrayname) . . .
2K - last updated 2012-03-18 23:21 UTC by g0pher

AwkFeatureComparison
This page lists which awk implementations support which features. Additions and corrections are very . . . |=Special characters in RE (\w etc.)|no|yes (but not in POSIX . . . |=using empty FS to split characters|no (undefined)|yes, but not in POSIX mode|yes|yes|no|no|unknown|no|no|yes| . . . RE|{{{echo aaa|awk '/a{3}/' # aaa}}}| |=Special characters in RE (\w etc.)|{{{echo 'a,b'|awk '/\<\w\W\w\>/' . . . # a,b}}}| |=using empty FS to split characters|{{{echo abc|awk -F '' '{print NF}' # 3}}}| . . .
4K - last updated 2015-04-27 13:23 UTC by pgas

AwkGuide
** Work in Progress ** {{{ import from Mark Hobley's wiki }}} <toc> ---- == Overview * [[Overview]] . . . * [[context]] * [[continuation]] character * [[control structure]]s * [[conversion qualifier]]s . . . * line [[continuation]] * [[list]]s * [[literal character]]s * [[locale]] * [[loop]]s * [[loop modifier]]s . . .
4K - last updated 2011-08-14 15:57 UTC by markhobley

AwkOnWindowsHowto
AwkOnWindowsHowto\\ rough cut - needs edit {{{ 3) awk command line switches/usage from a win32 cmd.exe . . . when n=-1 then message #: regular expression metacharacters: \ . ^ $ [ ] | + * ? ( ) #: filenames may . . .
3K - last updated 2010-10-24 07:44 UTC by g0pher

AwkTips
<toc> ---- == Be idiomatic! In this paragraph, we give some hints on how to write more idiomatic . . . to RS (the standard only allows a single literal character or an empty RS). That way, awk reads a series . . . course also use {{{FS=','}}}, and remove extra characters by hand: {{{ # FS=',' for(i=1;i<=NF;i++){ . . . separated by '=' (instead of the default newline character). If we look at the file as a series of records . . . parts of the input are delimited by different characters or string, like for example when we want . . .
31K - last updated 2009-03-24 16:54 UTC by waldner

backslash
In [[awk]], the backslash symbol can be used: * as a line [[continuation]] character * for suppression . . . within a regular expression]] * insert [[literal character]]s into a string . . .
1K - last updated 2011-05-09 22:34 UTC by markhobley

BackslashInRegexp
Because {{{"\\$"}}} is a string and {{{/\\$/}}} is not; in strings, some of the escape characters get . . . {{{"\\\\$"}}} . There are other, less obvious characters which need the same attention; under-quoting . . . special for alternation: {{{ /$test$/ => 6 characters `(test)' "$test$" => /(test)/ => . . . 4 characters `test' (with unused grouping) }}} An example . . . confusion regarding different forms of special characters; POSIX requires that {{{`\052'}}} be treated . . .
2K - last updated 2008-11-26 12:27 UTC by pgas

BeforeAfterMatch
Problem: print the Nth record before or after a certain regular expression matches or, alternativley, . . . if the pattern contains regular expression metacharacters, so in that case index() can be used instead . . .
3K - last updated 2009-02-28 20:38 UTC by waldner

case sensitivity
== Indentifier names == The [[awk]] interpreter is lettercase sensitive. This means that [[variable name]]s . . . case insensitive letter matching: ==== Using a character list ==== ==== Converting the data to lowercase . . .
1K - last updated 2011-06-25 05:14 UTC by pgas

CAWKLib
=CAWKLib CAWKlib is a library of functions for for awk intended to be used with preprocessors/wrappers . . . -- returns a string with the first character capitalized and the rest lowercase. If a . . . it is used as a separator and every first character after that separator character is capitalized. . . . -- reduce successive occurrences of a characters to one instance each *str_center() -- center . . . device *file_ischar() -- returns 1 if file is a character device *file_isdir() -- return 1 if file . . .
5K - last updated 2015-01-29 10:14 UTC by 108-243-116-77.lightspeed.cicril.sbcglobal.net

comment
Comments are pieces of text or [[whitespace]] that can be included in a program to make the code more . . . will ignore the [[hash]] symbol and any other characters that follow it until the end of the line: . . .
1K - last updated 2009-07-15 17:07 UTC by MarkHobley

comp.lang.awk FAQ
This material of this faq originates from the comp.lang.awk FAQ that you can find there: * http://www.faqs.org/faqs/computer-lang/awk/faq/ . . . answer]] ---- == How can I split a string into characters? <include "SplitIntoChars"> [[http://awk.freeshell.org/?action=edit;id=SplitIntoChars| . . .
8K - last updated 2009-03-04 12:42 UTC by pgas

comp.lang.awk FAQJapanese
This material of this faq originates from the comp.lang.awk FAQ that you can find there: * http://www.faqs.org/faqs/computer-lang/awk/faq/ . . . answer]] ---- == How can I split a string into characters? <include "SplitIntoCharsJapanese"> . . .
4K - last updated 2008-11-24 09:01 UTC by pgas

comparative operator
The comparative operators are used to determine equality or inequality or otherwise make comparisons . . . enclosures will be treated as strings of characters and compared lexically. The behaviour of . . .
3K - last updated 2013-02-24 17:38 UTC by markhobley

continuation
Line continuation enables long lines of code to split across several lines for the purpose of making . . . read. == The backslash symbol as a continuation character == In [[awk]], the [[backslash]] symbol can . . . be used as a continuation character, enabling a [[statement]] to be split across . . . \ "Hello World!" exit } }}} === Continuation characters must be appropriately placed within a statement . . . === In awk, a continuation character should not be placed in the middle of a [[keyword]], . . .
1K - last updated 2011-05-09 22:48 UTC by markhobley

ConvertHexToFloatingPoint
This code uses [[gawkism|gawk specific features]], such as the [[http://www.gnu.org/manual/gawk/html_node/Strtonum-Function.html][strtonum]] . . . { fval = 0 bias=127 # convert the character bytes into numbers i3=strtonum("0x" b3) i2=strtonum("0x" . . .
3K - last updated 2010-06-23 19:49 UTC by john b

dot
== The dot symbol == === The dot symbol as a regular expression operator === The [[dot]] symbol can be . . . expression operator]] to match any single character. A [[newline]] character can also be matched . . .
1K - last updated 2010-11-11 23:41 UTC by markhobley

escape sequence
Some characters cannot be included in [[literal string]]s, because they are [[nonprintable]] or [[control . . . character]]s, or characters that affect [[delimit]]ation . . . the strings, such as [[quotation mark]]s. These characters can be inserted by using an *escape sequence* . . . (known as *literal character notation*). == The backslash symbol can be . . . used to insert literal characters into a string An *escape sequence* consists . . .
3K - last updated 2008-12-30 13:07 UTC by Mark Hobley

FindAllIndices
Sometimes it is useful to find the index of every occurrence of a given character in a string. Let's . . . which may contain backslash-escaped quote characters. An easy way of doing this is..: # find . . . the index of every doublequote character; # perform a values-to-keys inversion on . . . numbers; # find the index of every backslash character; # for each backslash, if the index + 1 of . . . that it can be filled with indices of different characters by repeated invocation. The escaped-doublequote . . .
2K - last updated 2011-07-05 10:53 UTC by pgas

FIXES
[[FIXES]]        revised:   . . . with each character a single element.\\     made . . . (Mar 12, 1998)\\ \\ permit \n explicitly in character classes (Sep 24, 2000)\\ close() is now a . . . that wasn't opened.\\ added support for posix character class names like [:digit:] (Nov 16, 2001)\\ . . .
6K - last updated 2014-01-15 23:17 UTC by g0ph3r

Frequently Asked Questions
Some entries of this page have been copied from the [[comp.lang.awk_FAQ]]([[http://awk.freeshell.org/comp.lang.awk_FAQ#toc29|Credits]]) . . . this answer]] ---- == How do I PrintASingleQuote character? <include "PrintASingleQuote"> [[http://awk.freeshell.org/?action=edit;id=PrintASingleQuote| . . .
3K - last updated 2015-09-08 08:46 UTC by pgas

FS
= Field Separator = The [[special variable]] FS is a field separator that is used to determine how [[awk]] . . . value for the field separator is a single space character. In data files, fields are often separated . . . by multiple whitespace characters, rather than a single space. The awk interpreter . . . a special case in this manner. Any other single characters would be treated as delimiters for an empty . . . Note that the field separator can be a single character or a regular expression: {{{ # Change the . . .
5K - last updated 2013-02-19 21:45 UTC by markhobley

gawkism
Gawkisms are non portable syntax components that do not work with some awk implementations. The use of . . . [[mktime]] function * [[nextfile]] * [[newline]] characters after certain [[symbol]]s and [[keyword]]s . . .
2K - last updated 2011-05-19 22:29 UTC by markhobley

Glossary
[[Glossary| Glossary]]\\ see also [[AwkOnWindows| AwkOnWindows]] and [[FIXES| FIXES]] and [[AwkOnWindowsHowto| . . . function is entered.' B1.3 p.245 'White space characters are blank, tab, newline, carriage return, . . .
2K - last updated 2010-10-24 08:14 UTC by g0pher

Hello World in awk
This example program outputs the words "hello world" to the terminal: {{{ awk # Hello World BEGIN { print . . . which ignores the [[hash]] symbol and any other characters that follow it until the end of the line: . . . the [[print]] statement with a [[string]] of [[character]]s, which are output to the screen. . . .
2K - last updated 2010-11-11 19:16 UTC by markhobley

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

Inicio
Este wiki es mantenido por los usuarios del cenal **#awk** en **[[http://www.freenode.net|irc.freenode.net]]**. . . . código útiles * FindAllIndices of a particular character in a string * FindAllMatches of a particular . . .
7K - last updated 2009-02-12 23:31 UTC by fcr

length
== Usage == === length ([ STRING ]) === The **length** function returns the number of characters within . . .
1K - last updated 2011-06-25 05:11 UTC by pgas

line orientated
== The awk extraction and reporting language is line orientated == The [[awk]] extraction and reporting . . . \ { print $1 } }}} Note that line continuation characters must be appropriately placed within a [[rule]]. . . .
1K - last updated 2011-05-17 23:24 UTC by markhobley

literal characters
== Special characters cannot be directly included in a literal string == Special characters, such as . . . [[control character]]s or [[metacharacter]]s cannot be included . . . in a [[string]] value. This is because these [[character]]s have a special meaning to the [[awk]] . . . [[misbehaviour]] of the [[script]]. These [[character]]s can be inserted as literal characters . . . by using literal character notation. == Literal Character Notation == . . .
2K - last updated 2010-11-28 19:14 UTC by markhobley

mawk wish list
[[mawk_wish_list]]\\ mawk 1.3.4 from Thomas Dickey http://invisible-island.net/mawk/\\ his mawk is even . . . of changes since 1.3.3\\ eg he has added POSIX character classes;\\ WHINY_USERS sorted-array feature;\\ . . .
2K - last updated 2013-05-28 04:04 UTC by g0ph3r

MostrarApostrofos-español
Esta pregunta es tan frecuente que merece su propia respuesta. Y aunque pareciera que esto es una limitación . . . also the old fallback of putting a single quote character in its own variable and then using explicit . . .
4K - last updated 2009-01-15 20:03 UTC by fcr

Newline
"print" prints a newline by default. If you don't want a newline, you can use printf instead it is straightforward, . . . }}} If you want to join the lines with another characters you can do something like: {{{ sh awk '{printf . . . not the whole truth, in fact print adds the character in ORS, so you can also change ORS to "remove" . . .
1K - last updated 2011-07-05 10:53 UTC by pgas

numeric strings
Numeric strings obtained from the input source, will be treated as numeric values, when compared with . . . enclosures will be treated as strings of characters and compared lexically. The behaviour of . . .
5K - last updated 2013-02-24 17:40 UTC by markhobley

Overview of regular expressions
== What is a regular expression? == A regular expression is a method of representing a string matching . . . the pattern in relation to a line of text. * [[character set]]s used to match one or more characters . . . * [[modifier]]s used to specify how many times a character set is repeated. === Extended regular expression . . .
2K - last updated 2011-05-17 20:32 UTC by markhobley

PrimeNumberSieve
This is the standard sieve of Eratosthenes implemented in portable awk. The running time of the bare . . . record, and some very interesting performance characteristics when field accesses increase. |=algorithm|=10,000|=20,000|=30,000|=32,767|=1,000,000| . . .
4K - last updated 2008-06-19 05:56 UTC by gnomon

PrintASingleQuote
This question gets asked often enough that it deserves its own answer. This common question doesn't actually . . . shell quoting interacts with the singlequote character. === The Short Story Use octal [[escape sequence]]s . . . next most obvious solution - using hex-escaped characters - seems to work at first: {{{ awk 'BEGIN{print . . . but that [[gawk]] returns a [[multibyte]] character. As mentioned in paragraph 3 of the Rationale . . . also the old fallback of putting a single quote character in its own variable and then using explicit . . .
5K - last updated 2015-07-05 09:45 UTC by pitman

printf
== Usage == === printf [ FORMAT, LIST ] === The **printf** [[variadic]] function provides generic [[string . . . an [[output record separator]] or [[newline]] character to its output. The printf function provides . . . $i); print $i }' filename }}} Delete all newline characters in a file: {{{ awk '{printf "%s ",$O}' filename . . .
2K - last updated 2011-06-09 20:34 UTC by markhobley

RangeOfFields
Printing a range of fields - all fields but the first, for examples, or fields 3 through 8 - is a surprisingly . . . FS is not the default, but it's still a single character (for example, "#"), it is simpler and you . . . Using cut If the field separator is a single character, the {{{cut}}} utility may be used to select . . . field delimiters that are longer than a single character. By default, the delimiter is the tab character. . . . equivalent to the previous example. If a single-character delimiter limitation is not a restriction, . . .
10K - last updated 2015-09-08 09:52 UTC by pgas

ReadDirectory
Getting a list of files in a directory is a tricky process. One might be tempted to try use ls and getline, . . . ls is a bad idea]]. A file name can contain any character other than "/"(slash) and "\0"(null). Posix . . . (undefined behavior) and RS can only be a single character. This leaves us with "/" as the only reasonable . . .
2K - last updated 2013-10-03 22:35 UTC by emg

record
The awk utility divides its [[input]] into records and [[field]]s. == By default, each line of input . . . == Records are separated by a record separator character == Records are actually separated according . . . to the [[RS|record separator]] character. This has a default value of [[newline]], . . .
1K - last updated 2011-05-17 23:52 UTC by markhobley

regular expression operator
The [[awk]] programming language provides a set of *regular expression operators* that have special meanings . . . of a string | . | [[dot]] | Matches any single character including a newline == _Extended Regular . . . | The [[plus]] operator matches an operator or character at least once | ? | [[hook]] | The [[hook]] . . . operator matches an operator or character either once or not at all . . .
2K - last updated 2013-02-19 14:06 UTC by markhobley

RS
= Record Separator = The [[special variable]] RS is a record separator that is used to determine how . . . == The default record separator is a newline character == The default record separator is a newline . . . character, so by default each new line of data is treated . . . the final newline will be discarded. The newline character will always act as a field separator when . . . == Setting the record separator as a nul character == Note that in some implementations of [[awk]], . . .
3K - last updated 2013-02-19 23:11 UTC by markhobley

SedFAQ
<toc> ---- == I have a line like "abdcgfjeuPATTERNfjfhghj", I want to get the PATTERN part, why . . . the end of the string, and between any two characters in the string (if it cannot match a longer . . . occur multiple times, but PATTERN is a single character (assuming that makes sense for your problem), . . . like {{{sed sed 's/[^c]//g' }}} where "c" is the character, and remove all non-c characters, resulting . . . only, you need to do the following: ~* choose a character that does NOT appear in your input, let's . . .
34K - last updated 2010-02-14 17:56 UTC by waldner

SplitIntoChars
In portable POSIX awk, the only way to do this is to use substr to pull out each character, one by one. . . . anarray, "\001") for (i=1;i<=n;i++) print "character " i "is '" anarray[i] "'"; }}} . . .
1K - last updated 2008-11-24 08:20 UTC by pgas

SplitIntoCharsJapanese
In portable POSIX awk, the only way to do this is to use substr to pull out each character, one by one. . . . anarray, "\001") for (i=1;i<=n;i++) print "character " i "is '" anarray[i] "'"; }}} . . .
1K - last updated 2008-11-24 08:35 UTC by pgas

statement
The [[awk]] extraction and reporting language is not [[imperative]]. However, [[action]]s within the . . . statement in awk == In [[awk]], a newline character is considered the end of the statement, unless . . . a continuation character has been used at the end of the line. Each . . . across several lines by using a continuation character == The [[awk]] programming language allows . . . lines, by using a backslash [[continuation character]] at the end of the line to be continued: . . .
2K - last updated 2011-05-21 16:43 UTC by markhobley

string
== _Literal strings are delimited using doublequotes_ In [[awk]], literal strings are delimited using . . . notation can be used to include special characters_ It is possible to include [[special character]]s . . .
1K - last updated 2010-10-19 21:58 UTC by markhobley

string manipulation
* [[case conversion]] * [[length|Determine the length of a string]] * [[index|Determine the position . . . string]] * [[substr|Removing the first and last characters from a string]] * [[reverse|Reverse a string]] . . . from a string * Strip control codes and extended characters from a string * Test for an [[empty string]] . . .
1K - last updated 2011-07-04 22:12 UTC by markhobley

substr
=== Removing the first and last characters from a string === The following [[script]] demonstrates how . . . can be combined to remove the first and last [[character]]s from a [[string]]: {{{ awk BEGIN { mystring="knights" . . . # remove the last character print substr(mystring,2,length(mystring)-2) . . . # remove both the first and last character } }}} . . .
1K - last updated 2011-06-25 05:10 UTC by pgas

suppression of interpolation within a regular expression
The [[backslash]] symbol is be used to prevent [[interpolation]] of [[metacharacter]]s within the program. . . . By prefixing the special character with a backslash metacharacter, we prevent . . .
1K - last updated 2010-02-01 20:54 UTC by MarkHobley

text.2.wiki.awk
#:       C:\#\awk\lib\text.2.wiki.awk\\ . . . Converts literal \240 to the character \240 == \xa0 - non breaking . . . w..z reals\\ {{{ #: regular expression metacharacters: \ ^ $ . [ ] | ( ) * + ? escape with \ }}} . . .
11K - last updated 2012-09-24 14:55 UTC by g0ph3r

text 2 wiki.awk
{{{ #: C:\#\lib\awk\utl\text_2_wiki.awk #: 2012-09-15 23:40:11 #:rod.t_2012 #: This file is http://awk.freeshell.org/text_2_wiki.awk . . . to make bold; [[...| the \xa0=\240 nbsp; character #: %awk% -f C:\#\lib\awk\utl\text_2_wiki.awk . . . integers; w..z reals #: regular expression metacharacters: \ ^ $ . [ ] | ( ) * + ? escape with \ #: . . .
2K - last updated 2012-09-16 09:12 UTC by g0ph3r

WartAndWishList
Awk is a wonderful language! That said, there are a few annoying bits... == The Good * well-documented . . . of interpretation. A string can contain escaped characters which must be interpreted ({{{"A string . . . with an embedded \t tab character \n And a newline}}}); if a string is used . . .
7K - last updated 2009-04-13 18:39 UTC by goedel

whitespace
== _Line breaks are best placed at whitespace points_ The [[awk]] extraction and reporting language is . . . [[line orientated]]. This means that [[newline]] characters cannot be used to create a line break at . . . In traditional awk implementations a [[newline]] character can be inserted at the end of a [[command]] . . .
1K - last updated 2011-03-20 22:07 UTC by markhobley

56 pages found.