Cut

Cut is a Unix command-line tool used to extract fields and the like from lines of input, available on many platforms.

Options

Command-line options aka switches of cut:

-clist: Display selected characters of lines.
-flist: Display selected fields of lines, separated by tab by default.
-dchar: Switch field separator from tab to char.
-s: Do not display ("suppress") lines that contain no occurrence of the field separator.

Command-line options aka switches of some versions of cut:

Examples of cut use:

cut -f1 file.txt
- Displays the 1st field of each line, using tab as the field separator.
echo a:b | cut -d: -f2
- Displays the 2nd field of each line, using colon as the field separator.
echo a b c | cut -d" " -f1,3
echo a b c d e | cut -d" " -f1-3,5
echo a b c | cut -d" " -f3,2,1
- Outputs "a b c", disregarding the reversed order after -f.
echo a b c d | cut -d" " -f2-
- Outputs the 2nd and every later field, so "b c d".
echo abcd | cut -c3,4
- Instead of fields, treats characters. Thus, outputs "cd".
echo abcdefgh | cut -c1-3,6-8
- Outputs abcfgh

Examples of use of similar tools in cut's domain:

echo a b|awk '{print $2}'
- Displays "b", separating fields by any number of tabs or spaces. Thus, for awk, "b" is the 2nd field, while for cut -d" ", "b" is the 3rd field.
echo a b|awk '{print $2 $1}'
- Displays "ba", preserving the order of the fields as specified.
echo a b|sed "s/ */ /g" |cut -f2 -d" "
- Displays "b". Uses sed to first compact a sequence of spaces into a single space.

Cut is subject to the following limitations:

There is no way to specify "one or more spaces" or the like as the field delimiter.
There is no way to change the order of the fields on the output.

Note: Some people find that awk or gawk is able to meet needs where cut is too limited.

A version of GNU cut for MS Windows is available from GnuWin32 project, as well as from Cygwin.