8.1 cut: Print selected parts of lines ¶

cut writes to standard output selected parts of each line of each input file, or standard input if no files are given or for a file name of ‘-’. Synopsis:

cut option... [file]...

In the table which follows, the byte-list, character-list, and field-list are one or more numbers or ranges (two numbers separated by a dash) separated by commas. Bytes, characters, and fields are numbered starting at 1. Incomplete ranges may be given: -m means ‘1-m’; ‘n-’ means ‘n’ through end of line or last field. The list elements can be repeated, can overlap, and can be specified in any order; but the selected input is written in the same order that it is read, and is written exactly once.

The program accepts the following options. Also see Common options.

‘-b byte-list’ ¶

‘--bytes=byte-list’

Select for printing only the bytes in positions listed in byte-list. Tabs and backspaces are treated like any other character; they take up 1 byte. If an output delimiter is specified, (see the description of --output-delimiter), then output that string between ranges of selected bytes.

‘-c character-list’ ¶

‘--characters=character-list’

Select for printing only the characters in positions listed in character-list. Tabs and backspaces are treated like any other character; they take up 1 character. Combining characters are considered as separate characters. If an output delimiter is specified, (see the description of --output-delimiter), then output that string between ranges of selected characters.

‘--complement’ ¶

This option is a GNU extension. Select for printing the complement of the bytes, characters or fields selected with the -b, -c or -f options. In other words, do not print the bytes, characters or fields specified via those options. This option is useful when you have many fields and want to print all but a few of them.

‘-d character’ ¶

‘--delimiter=character’

With -f, use character as the input field separator (default is TAB). If an empty delimiter character is specified then the ASCII NUL character is used to delimit the fields. Note the delimiter character can be the same as the line terminator character, which can be used to select ranges of lines. In this case the last line terminator in the input is not treated as a field separator, which is significant with the -s option.

‘-f field-list’ ¶

‘--fields=field-list’

Select for printing only the fields listed in field-list. Fields are separated by a TAB character by default. Also print any line that contains no delimiter character, unless the --only-delimited (-s) option is specified.

The awk command supports more sophisticated field processing, like reordering fields, and handling fields aligned with blank characters. By default awk uses (and discards) runs of blank characters to separate fields, and ignores leading and trailing blanks.

awk '{print $2}'      # print the second field
awk '{print $(NF-1)}' # print the penultimate field
awk '{print $2,$1}'   # reorder the first two fields

While cut accepts field specifications in arbitrary order, output is always in the order encountered in the file.

In the unlikely event that awk is unavailable, one can use the join command, to process blank characters as awk does above.

join -a1 -o 1.2     - /dev/null # print the second field
join -a1 -o 1.2,1.1 - /dev/null # reorder the first two fields

‘-F’ ¶

Like the -f,--fields option, but also implies -w and --output-delimitor=' '. I.e., fields are separated by runs of blank characters, and output fields are separated by a single ASCII space.

‘-n’ ¶

‘--no-partial’

With --bytes, do not split multi-byte characters. A byte range must encompass the end of a multi-byte character for it to be selected.

‘-O string’ ¶

‘--output-delimiter=string’

With -f, output fields are separated by string. The default with -f is to use the input delimiter, or with -w the TAB character. When using -b or -c to select ranges of byte or character offsets (as opposed to ranges of fields), output output_delim_string between non-overlapping ranges of selected bytes.

‘-s’ ¶

‘--only-delimited’

For -f, do not print lines that do not contain field separators. Normally, any line without a field separator is printed verbatim. With --whitespace-delimited=trimmed, lines that contain only leading or trailing blanks will be suppressed.

‘-w’ ¶

‘--whitespace-delimited[=trimmed]’

With -f, separate fields with a run of blank characters (usually space or TAB). With ‘trimmed’ do not consider leading and trailing blanks as field separators. -w is implied with the -F option.

‘-z’ ¶

‘--zero-terminated’

Delimit items with a zero byte rather than a newline (ASCII LF). I.e., treat input as items separated by ASCII NUL and terminate output items with ASCII NUL. This option can be useful in conjunction with ‘perl -0’ or ‘find -print0’ and ‘xargs -0’ which do the same in order to reliably handle arbitrary file names (even those containing blanks or other special characters).

An exit status of zero indicates success, and a nonzero value indicates failure.