cut.md

cut

cut is a command-line tool for selecting specific fields and characters from input.

Selecting fields

By default, cut splits input on the tab character. The -f option can be used to specify which fields to select in each line.

$ printf "mat\tcat\that\ntore\tbore\tfore" | cut -f 2
cat
bore

The -f option also accepts comma-separated values, in which duplicate field numbers will be ignored, and ranges using the - character. Range values can emit either the start or end value, but not both.

# comma-separated values for fields
$ printf "mat\tcat\that\ntore\tbore\tfore" | cut -f 1,3
mat     hat
tore    fore

# range value with both start and end
$ printf "mat\tcat\that\ntore\tbore\tfore" | cut -f 1-2
mat     cat
tore    bore

# range value with end omitted
$ printf "mat\tcat\that\ntore\tbore\tfore" | cut -f 2- 
cat     hat
bore    fore

# range value with start omitted
$ printf "mat\tcat\that\ntore\tbore\tfore" | cut -f -2
mat     cat
tore    bore

# range value with start and end omitted
$ printf "mat\tcat\that\ntore\tbore\tfore" | cut -f -
cut: [-bcf] list: values may not include zero

If a line does not have the specified field, a blank line will be output.

$ printf "mat\tcat\that\ntore\tbore\tfore" | cut -f 4

Delimiters

The -d option can be used to change the input delimiter, however, only a single byte character is allowed.

$ printf "mat,cat,hat\ntore,bore,fore" | cut -d , -f 2
cat
bore

$ printf "mat,cat,hat\ntore,bore,fore" | cut -d ',,' -f 2
cut: bad delimiter

By default, the input delimiter is also used at the output delimiter, but that can be changed via the --output-delimiter option, which can be set to any string.

Complements

The --complement option allows for selecting the inverse of the specified selection.

$ printf "mat,cat,hat\ntore,bore,fore" | cut -d , -f 1,3 --complement
cat
bore

Suppression

By default, input lines that do not contain the input delimiter will be included in the output. The -s option suppresses the emission of these lines in the output.

# first line does not have any tabs
$ printf "mat,cat,hat\ntore\tbore\tfore" | cut -f 1,3 -s
tore    fore

Character selection

The -b or -c option can be used to select specific bytes of characters from input.

$ printf "mat\tcat\that\ntore\tbore\tfore" | cut -c 3,6,9,12
tah
rbeo

$ printf "mat\tcat\that\ntore\tbore\tfore" | gcut -c 3,6,9,12 --complement
ma      ct      at
toe     or      fre