xref: /freebsd/usr.bin/cut/cut.1 (revision bdcbfde31e8e9b343f113a1956384bdf30d1ed62)

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.Dd November 6, 2022
.Dt CUT 1
.Os
.Sh NAME
.Nm cut
.Nd cut out selected portions of each line of a file
.Sh SYNOPSIS
.Nm
.Fl b Ar list
.Op Fl n
.Op Ar
.Nm
.Fl c Ar list
.Op Ar
.Nm
.Fl f Ar list
.Op Fl w | Fl d Ar delim
.Op Fl s
.Op Ar
.Sh DESCRIPTION
The
.Nm
utility cuts out selected portions of each line (as specified by
.Ar list )
from each
.Ar file
and writes them to the standard output.
If no
.Ar file
arguments are specified, or a file argument is a single dash
.Pq Sq Fl ,
.Nm
reads from the standard input.
The items specified by
.Ar list
can be in terms of column position or in terms of fields delimited
by a special character.
Column and field numbering start from 1.
.Pp
The
.Ar list
option argument
is a comma or whitespace separated set of increasing numbers and/or
number ranges.
Number ranges consist of a number, a dash
.Pq Sq \- ,
and a second number
and select the columns or fields from the first number to the second,
inclusive.
Numbers or number ranges may be preceded by a dash, which selects all
columns or fields from 1 to the last number.
Numbers or number ranges may be followed by a dash, which selects all
columns or fields from the last number to the end of the line.
Numbers and number ranges may be repeated, overlapping, and in any order.
It is not an error to select columns or fields not present in the
input line.
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl b Ar list
The
.Ar list
specifies byte positions.
.It Fl c Ar list
The
.Ar list
specifies character positions.
.It Fl d Ar delim
Use
.Ar delim
as the field delimiter character instead of the tab character.
.It Fl f Ar list
The
.Ar list
specifies fields, separated in the input by the field delimiter character
(see the
.Fl d
option).
Output fields are separated by a single occurrence of the field delimiter
character.
.It Fl n
Do not split multi-byte characters.
Characters will only be output if at least one byte is selected, and,
after a prefix of zero or more unselected bytes, the rest of the bytes
that form the character are selected.
.It Fl s
Suppress lines with no field delimiter characters.
Unless specified, lines with no delimiters are passed through unmodified.
.It Fl w
Use whitespace (spaces and tabs) as the delimiter.
Consecutive spaces and tabs count as one single field separator.
.El
.Sh ENVIRONMENT
The
.Ev LANG , LC_ALL
and
.Ev LC_CTYPE
environment variables affect the execution of
.Nm
as described in
.Xr environ 7 .
.Sh EXIT STATUS
.Ex -std
.Sh EXAMPLES
Extract users' login names and shells from the system
.Xr passwd 5
file as
.Dq name:shell
pairs:
.Pp
.Dl "cut -d : -f 1,7 /etc/passwd"
.Pp
Show the names and login times of the currently logged in users:
.Pp
.Dl "who | cut -c 1-16,26-38"
.Sh SEE ALSO
.Xr colrm 1 ,
.Xr paste 1
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.2-92 .
.Pp
The
.Fl w
flag is an extension to the specification.
.Sh HISTORY
A
.Nm
command first appeared in
.Bx 4.3 Reno .
.Sh AUTHORS
.An -nosplit
The original Bell Labs version was written by
.An Gottfried W. R. Luderer
and the
.Bx
version by
.An Adam S. Moskowitz .