cut(1)cut(1)NAMEcut - cut out (extract) selected fields of each line of a file
SYNOPSIS
list [file]...
list [file]...
list char] [file]...
DESCRIPTION
cuts out (extracts) columns from a table or fields from each line in a
file; in data base parlance, it implements the projection of a rela‐
tion. Fields as specified by list can be fixed length (defined in
terms of character or byte position in a line when using the or
option), or the length can vary from line to line and be marked with a
field delimiter character such as the tab character (when using the
option). The input files must be text files, except that line lengths
are not limited to LINE_MAX characters. can be used as a filter; if no
files are given, the standard input is used.
When processing single-byte character sets, the and options are equiva‐
lent and produce identical results. When processing multi-byte charac‐
ter sets, when the and options are used together, their combined behav‐
ior is very similar, but not identical to the option.
Options
Options are interpreted as follows:
list A comma-separated list of integer byte option),
character option), or field option) numbers, in
increasing order, with optional to indicate
ranges. For example:
Positions 1, 4, and 7.
Positions 1 through 3 and 8.
Positions 1 through 5 and 10.
Position 3 through last position.
Cut based on a list of bytes.
Each selected byte is output unless the option is
also specified.
Cut based on character positions specified by
list extracts the first 72 characters of each
line).
Where list is a list of fields assumed to be separated
in the file by a delimiter character (see for
example, copies the first and seventh field only.
Lines with no field delimiters will be passed
through intact (useful for table subheadings),
unless is specified.
The character following
is the field delimiter option only). Default is
tab. Space or other characters with special
meaning to the shell must be quoted. Adjacent
field delimiters delimit null fields. char may
be an international code set character.
Do not split characters.
If the high end of a range within a list is not
the last byte of a character, that character is
not included in the output. However, if the low
end of a range within a list is not the first
byte of a character, the entire character is
included in the output."
Suppresses lines with no delimiter characters when using
option. Unless is specified, lines with no
delimiters appear in the output without alter‐
ation.
Hints
Use to extract text from a file based on text pattern recognition
(using regular expressions). Use to merge files line-by-line in colum‐
nar format. To rearrange columns in a table in a different sequence,
use and See grep(1) and paste(1) for more information.
EXTERNAL INFLUENCES
Environment Variables
determines the interpretation of text as single and/or multi-byte char‐
acters.
If is not specified in the environment or is set to the empty string,
the value of is used as a default for each unspecified or empty vari‐
able. If is not specified or is set to the empty string, a default of
"C" (see lang(5)) is used instead of If any internationalization vari‐
able contains an invalid setting, behaves as if all internationaliza‐
tion variables are set to "C". See environ(5).
International Code Set Support
supports both single- and multi-byte character code sets. Interna‐
tional code set characters may be specified in the char given to the
option. recognizes the international code set characters according to
the locale specified in the environment variable.
EXAMPLES
Password file mapping of user ID to user names:
Set environment variable to current login name:
Convert file containing lines of arbitrary length into two files where
contains the first 500 bytes (unless the 500th byte is within a multi-
byte character), and contains the remainder of each line:
DIAGNOSTICS
Missing or option or incorrectly specified list. No error
occurs if a line has fewer fields than the list calls
for.
list is empty.
WARNINGS
does not expand tabs. Pipe text through expand(1) if tab expansion is
required.
Backspace characters are treated the same as any other character. To
eliminate backspace characters before processing by use the or command
(see fold(1) and col(1)).
AUTHOR
was developed by OSF and HP.
SEE ALSOgrep(1), paste(1).
STANDARDS CONFORMANCEcut(1)