fmt

Reformat a text file by joining its paragraphs and limiting the line width to given number of characters (75 by default).

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}}