cut

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cut extracts columns from text. For each line of input it prints only the parts you select, dropping the rest.

cut option... [file...]

$ cut -d , -f 1,3 people.csv     # the 1st and 3rd comma-separated field
$ cut -c 1-8 log.txt             # the first 8 characters of each line

Every run of cut needs two decisions: what counts as a column, and which columns to keep.

What counts as a column #

Choose exactly one mode:

Option	A column is…
`-b`, `--bytes`	a single byte.
`-c`, `--characters`	a single character.
`-f`, `--fields`	a field — a stretch of text between delimiters.

-b and -c cut by position. -f cuts by field, which is what you want for tabular data — a CSV, a table, the columns of a report.

The mode option takes a sequence: numbers and inclusive ranges, separated by commas.

Sequence	Selects
`3`	column 3 only.
`2,5,9`	columns 2, 5, and 9.
`5-7`	columns 5 through 7.
`3-`	column 3 to the end of the line.
`-4`	the start of the line through column 4.
`1,4-6,9`	any mixture of the above.

Option	Effect
`--complement`	Invert the selection — keep every column except those named.

In field mode, cut needs to know what separates the fields.

Option	Effect
`-d`, `--delimiter=CHAR`	The character that separates fields. The default is a tab.
`-w`	Separate fields on runs of whitespace (spaces and tabs) instead of a single character. Cannot be combined with `-d`.
`-s`, `--only-delimited`	Print only lines that actually contain the delimiter; drop lines that have no fields to cut.
`--output-delimiter=STRING`	Put `STRING` between the kept fields in the output, instead of repeating the input delimiter — handy for converting one delimited format to another.

Option	Effect
`-z`, `--zero-terminated`	Treat the NUL character as the line delimiter, so a "line" may itself contain newlines.

Code	Meaning
`0`	Success.
`1`	A mode was missing or given twice, an option was misused, or a file could not be read.