fmt

fmt [-WIDTH] [OPTION]... [FILE]...

Reformat paragraphs from input files (or stdin) to stdout.

Options

--crown-margin, -c

First and second line of paragraph may have different indentations, in which case the first line's indentation is preserved, and each subsequent line's indentation matches the second line.

--tagged-paragraph, -t

Like -c, except that the first and second line of a paragraph must have different indentation or they are treated as separate paragraphs.

--preserve-headers, -m

Attempt to detect and preserve mail headers in the input. Be careful when combining this flag with -p.

--split-only, -s

Split lines only, do not reflow.

--uniform-spacing, -u

Insert exactly one space between words, and two between sentences. Sentence breaks in the input are detected as [?!.] followed by two spaces or a newline; other punctuation is not interpreted as a sentence break.

--prefix=<PREFIX>, -p <PREFIX>

Reformat only lines beginning with PREFIX, reattaching PREFIX to reformatted lines. Unless -x is specified, leading whitespace will be ignored when matching PREFIX.

--skip-prefix=<PSKIP>, -P <PSKIP>

Do not reformat lines beginning with PSKIP. Unless -X is specified, leading whitespace will be ignored when matching PSKIP

--exact-prefix, -x

PREFIX must match at the beginning of the line with no preceding whitespace.

--exact-skip-prefix, -X

PSKIP must match at the beginning of the line with no preceding whitespace.

--width=<WIDTH>, -w <WIDTH>

Fill output lines up to a maximum of WIDTH columns, default 75. This can be specified as a negative number in the first argument.

--goal=<GOAL>, -g <GOAL>

Goal width, default of 93% of WIDTH. Must be less than or equal to WIDTH.

--quick, -q

Break lines more quickly at the expense of a potentially more ragged appearance.

--tab-width=<TABWIDTH>, -T <TABWIDTH>

Treat tabs as TABWIDTH spaces for determining line length, default 8. Note that this is used only for calculating line lengths; tabs are preserved in the output.

Examples

Reformat a file:

fmt {{path/to/file}}

Reformat a file producing output lines of (at most) n characters:

fmt -w {{n}} {{path/to/file}}

Reformat a file without joining lines shorter than the given width together:

fmt -s {{path/to/file}}

Reformat a file with uniform spacing (1 space between words and 2 spaces between paragraphs):

fmt -u {{path/to/file}}

The examples are provided by the tldr-pages project under the CC BY 4.0 License.

Please note that, as uutils is a work in progress, some examples might fail.