Editing Cut (Unix)

{{Short description|Command line utility}}{{lowercase title}}
{{For|the more common operation related to copying and pasting|Cut, copy, and paste}}
{{Infobox software
| name                   = cut
| logo                   = 
| screenshot             = 
| screenshot size        = 
| caption                = 
| author                 = [[AT&T Bell Laboratories]]
| developer              = Various [[open-source software|open-source]] and [[commercial software|commercial]] developers
| released               = {{Start date and age|1985|2}}
| latest release version = 
| latest release date    = 
| operating system       = [[Unix]], [[Unix-like]], [[IBM i]]
| platform               = [[Cross-platform]]
| genre                  = [[Command (computing)|Command]]
| license                = [[coreutils]]: [[GPLv3+]]
| website                = 
}}
In [[computing]], <code>'''cut'''</code> is a [[Command-line interface|command line]] utility on [[Unix]] and [[Unix-like]] [[operating system]]s which is used to extract sections from each line of input — usually from a [[computer file|file]]. It is currently part of the [[GNU Core Utilities|GNU coreutils]] package and the [[Berkeley Software Distribution|BSD]] Base System.

Extraction of line segments can typically be done by [[byte]]s (<code>-b</code>), [[character (computing)|character]]s (<code>-c</code>), or fields (<code>-f</code>) separated by a delimiter (<code>-d</code> &mdash; the [[tab character]] by default). A range must be provided in each case which consists of one of <code>N</code>, <code>N-M,</code> <code>N-</code> (<code>N</code> to the end of the line), or <code>-M</code> (beginning of the line to <code>M</code>), where N and M are counted from 1 (there is no zeroth value). Since version 6, an error is thrown if you include a zeroth value. Prior to this the value was ignored and assumed to be 1.

==History==
The original [[Bell Labs]] version was written by [[Gottfried W. R. Luderer]].<ref>{{Cite web|url=https://man.openbsd.org/cut.1|title=cut(1) - OpenBSD manual pages}}</ref><ref>{{Cite web|url=https://www.tuhs.org/pipermail/tuhs/2020-January/019955.html|title=[TUHS] A portrait of cut(1)|date=15 January 2020 }}</ref> {{code|cut}} is part of the [[X/Open]] Portability Guide since issue 2 of 1987. It was inherited into the first version of POSIX.1 and the [[Single Unix Specification]].<ref>{{man|cu|cut|SUS}}</ref> It first appeared in [[UNIX System III|AT&T System III UNIX]] in 1982.<ref>{{man|1|cut|FreeBSD}}</ref>

The version of <code>cut</code> bundled in [[GNU]] [[coreutils]] was written by David M. Ihnat, David MacKenzie, and Jim Meyering.<ref>{{man|1|cut|ManKier}}</ref> The command is available as a separate package for [[Microsoft Windows]] as part of the [[UnxUtils]] collection of [[Native (computing)|native]] [[Windows API|Win32]] [[porting|ports]] of common GNU Unix-like utilities.<ref>{{Cite web|url=http://unxutils.sourceforge.net/|title=Native Win32 ports of some GNU utilities|website=unxutils.sourceforge.net}}</ref> The {{Mono|cut}} command has also been ported to the [[IBM i]] operating system.<ref>{{cite web |title=IBM System i Version 7.2 Programming Qshell |language=en |author=IBM |website=[[IBM]] |author-link=IBM |url=https://www.ibm.com/support/knowledgecenter/ssw_ibm_i_74/rzahz/rzahzpdf.pdf?view=kc |access-date=2020-09-05 |url-status=live|archive-url=https://web.archive.org/web/20200918130823/https://www.ibm.com/support/knowledgecenter/ssw_ibm_i_74/rzahz/rzahzpdf.pdf?view=kc |archive-date=2020-09-18 }}</ref>

==Examples==
Assuming a file named "<code>file</code>" containing the lines:
 foo:bar:baz:qux:quux
 one:two:three:four:five:six:seven
 alpha:beta:gamma:delta:epsilon:zeta:eta:theta:iota:kappa:lambda:mu
 the quick brown fox jumps over the lazy dog

To output the fourth through tenth characters of each line:
<syntaxhighlight lang="console">
$ cut -c 4-10 file
:bar:ba
:two:th
ha:beta
 quick 
</syntaxhighlight>
To output the fifth field through the end of the line of each line using the [[colon (punctuation)|colon character]] as the field delimiter:
<syntaxhighlight lang="console">
$ cut -d ":" -f 5- file
quux
five:six:seven
epsilon:zeta:eta:theta:iota:kappa:lambda:mu
the quick brown fox jumps over the lazy dog
</syntaxhighlight>

(note that because the [[colon (punctuation)|colon character]] is not found in the last line the entire line is shown)

Option <code>-d</code> specifies a single character delimiter (in the example above it is a colon) which serves as field separator. Option <code>-f</code> which specifies range of fields included in the output (here fields range from five till the end). Option <code>-d</code> presupposes usage of option <code>-f</code>.

To output the third field of each line using space as the field delimiter:
<syntaxhighlight lang="console">
$ cut -d " " -f 3 file
foo:bar:baz:qux:quux
one:two:three:four:five:six:seven
alpha:beta:gamma:delta:epsilon:zeta:eta:theta:iota:kappa:lambda:mu
brown
</syntaxhighlight>
(Note that because the space character is not found in the first three lines these entire lines are shown.)

To separate two words having any delimiter:
<syntaxhighlight lang="console">
$ line=process.processid
$ cut -d "." -f1 <<< $line
process
$ cut -d "." -f2 <<< $line
processid
</syntaxhighlight>

==Syntax==
 cut [-b list] [-c list] [-f list] [-n] [-d delim] [-s] [file]

Flags which may be used include:
; {{mono|-b}} : Bytes; a list following {{mono|-b}} specifies a range of [[byte]]s which will be returned, e.g. {{code|cut -b1-66}} would return the first 66 bytes of a line. NB If used in conjunction with {{mono|-n}}, no [[multi-byte]] characters will be split. NNB. {{mono|-b}} will only work on input lines of less than 1023 bytes
; {{mono|-c}} : Characters; a list following {{mono|-c}} specifies a range of characters which will be returned, e.g. {{code|cut -c1-66}} would return the first 66 characters of a line
; {{mono|-f}} : Specifies a field list, separated by a [[delimiter]]
; list : A comma separated or blank separated list of integer denoted fields, incrementally ordered. The {{mono|-}} indicator may be supplied as shorthand to allow inclusion of ranges of fields e.g. {{mono|4-6}} for ranges 4–6 or {{mono|5-}} as shorthand for field 5 to the end, etc.
; {{mono|-n}} : Used in combination with -b suppresses splits of [[multi-byte character]]s
; {{mono|-d}} : Delimiter; the character immediately following the {{mono|-d}} option is the field delimiter for use in conjunction with the {{mono|-f}} option; the default delimiter is ''tab''. Space and other characters with special meanings within the context of the [[Unix shell|shell]] in use must be enquoted or escaped as necessary.
; {{mono|-s}} : Bypasses lines which contain no field delimiters when {{mono|-f}} is specified, unless otherwise indicated.
; file : The file (and accompanying path if necessary) to process as input. If no file is specified then [[standard input]] will be used.

==See also==
* [[List of Unix commands]]
* [[grep]]
* [[paste (Unix)]]
* [[sed]]
* [[awk]]

==References==
{{Reflist}}

==External links==
{{Wikibooks|Guide to Unix|Commands}}
* {{man|cu|cut|SUS}}
* [http://www.softpanorama.org/Tools/cut.shtml Softpanorama cut page].
* [http://marmaro.de/docs/freiesmagazin/cut/cut.en.pdf Cut out selected fields of each line of a file] A portrait of cut(1) and its historical background.

{{Unix commands}}
{{Core Utilities commands}}

[[Category:Unix text processing utilities]]
[[Category:Standard Unix programs]]
[[Category:Unix SUS2008 utilities]]
[[Category:IBM i Qshell commands]]