fold -- filter for folding lines


fold [ -bs ] [ -w width] [file ... ]


fold breaks lines by inserting a newline character, so that no output line exceeds a maximum width. fold reads the named files (or the standard output if no files are named) and writes to the standard output. It is usually used to send files to printers that truncate long lines.

If a carriage return, backspace or tab character is found in the input (and the -b option is not specified) then it is treated as follows:

The current line position is decremented by one. A newline character is not inserted immediately before or after a backspace character.

carriage return
The current line position is reset to zero. A newline character is not inserted immediately before or after a carriage return.

The current line position is advanced to the next tab stop. Tab stops are set every eighth column.
The following options are recognized by fold:

Turn off the special treatment of backspace, carriage return and tab characters (as described above).

If a line contains blank characters within the first width positions, break the line after the last such blank character. (If there is no such blank character, the -s has no effect.) This option is useful for readable text files; it ensures that lines are broken on word boundaries rather than in the middle of a word.

-w width
width is the column width in column positions. The default value is 80.

Exit values

An exit value of 0 indicates that the files were processed successfully. An exit value greater than 0 indicates that an error occurred.


fold -s -w72 <myfile.txt >myfile.txt.2

Filters myfile.txt to myfile.txt.2, breaking lines at the last blank character encountered within a width of 72 columns.


Input files must be text files with lines limited to {LINE_MAX} bytes in length, unless the -b option is given.

See also

cut(C), expand(C)

Standards conformance

fold is conformant with:

ISO/IEC DIS 9945-2:1992, Information technology - Portable Operating System Interface (POSIX) - Part 2: Shell and Utilities (IEEE Std 1003.2-1992);
X/Open CAE Specification, Commands and Utilities, Issue 4, 1992.

© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003