Linux cut command

The Linux cut command is used to display the text from num1 to num2 counting from the beginning of each line.

cut  [-bn] [file]
cut [-c] [file]
cut [-df] [file]

Instructions:

The cut command cuts bytes, characters, and fields from each line of a file and writes these bytes, characters, and fields to standard output.

If the File parameter is not specified, the cut command reads standard input. One of the -b, -c, or -f flags must be specified.

Parameters:

-b: Split in bytes. These byte positions will ignore multi-byte character boundaries unless the -n flag is also specified.
-c: Split in characters.
-d: Custom delimiter, default is a tab.
-f: Used with -d to specify which region to display.
-n: Cancel splitting multi-byte characters. Only used with the -b flag. If the last byte of a character falls within the range indicated by the List parameter of the -b flag,
the character will be written out; otherwise, the character will be excluded.

When you execute the who command, it outputs something like the following:

$ who
rocrocket :0           2009-01-08 11:07
rocrocket pts/0        2009-01-08 11:23 (:0.0)
rocrocket pts/1        2009-01-08 14:15 (:0.0)

If we want to extract the 3rd byte of each line, do this:

$ who|cut -b 3
c
c

Other extensions

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