fold(1)								      fold(1)



NAME

  fold - Breaks or wraps lines in a file

SYNOPSIS

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

  The fold command wraps lines in the specified files.	If a file is not
  specified, standard input is the default.  All lines are wrapped to meet
  the maximum width specified.

FLAGS

  -b  Specifies that width be counted in bytes rather than in column posi-
      tions.  Using the -b flag does not limit lines to LINE_MAX bytes.

  -s  Breaks (or wraps) a line if a segment of the line contains a blank
      character in the first width column position (or bytes).	This enables
      the line to meet width constraints.  If a blank character is not in the
      correct width column position, the -s flag has no affect on that input
      line.

  -w width or -width
      Specifies the maximum width to use when lines are wrapped in column
      positions (or bytes if the -b flag is specified).	 Either -w width or
      -width is acceptable input where width is the number of column posi-
      tions (or bytes).	 The default value is 80.

      If the CMD_ENV environment variable is set to svr4 (System V Release
      4), you must use -width to specify the number of column positions (or
      bytes).

DESCRIPTION

  The fold command is a filter that wraps lines from the specified input
  files or standard input to a maximum of width (or bytes, if the -b flag is
  specified).  The fold command wraps lines by inserting a newline character
  into the output so that each output line is the maximum column positions or
  bytes specified.  A line cannot be broken in the middle of a character.

  The fold command is often used to send text files to line printers that
  truncate, rather than wrap, lines wider than the printer is able to print
  (usually 80 or 132 column positions).

  If the , , or  characters are encountered
  in the input, and the -b flag is not specified, these characters are
  treated specially:

  
      The current count of line width is decremented by one, although the
      count never becomes negative.  The fold command does not insert a new-
      line character immediately before or after any backspace character.

  
      Each tab character encountered advances the column position pointer to
      the position of the next tab stop.  Tab stops are at each column posi-
      tion number, such that number modulo 8 equals 1.

  
      The current count of the line width is set to zero (0).  The fold com-
      mand does not insert a newline immediately before or after any
      carriage-return.

  Note that the fold command possibly affects underlining in a file.

EXAMPLES

  The fold command can be used to prepare files to be joined side-by-side
  with the paste command.  For example, the contents of two files, az and AZ
  follows:

       aaaa bbbb cccc dddd eeee ffff gggg hhhh iiii jjjj kkkk llll mmmm
       nnnn oooo pppp qqqq rrrr ssss tttt uuuu vvvv wwww xxxx yyyy zzzz

       AAAA BBBB CCCC DDDD EEEE FFFF GGGG HHHH IIII JJJJ KKKK LLLL MMMM
       NNNN OOOO PPPP QQQQ RRRR SSSS TTTT UUUU VVVV WWWW XXXX YYYY ZZZZ


  To display the az and AZ files side-by-side, use the following command
  line:

       fold -w 32 az > az2; fold -w 32 AZ > AZ2; paste -d" " az2 AZ2


  Executing the previous command line results in the following output:

aaaa bbbb cccc dddd eeee ffff gg AAAA BBBB CCCC DDDD EEEE FFFF GG
gg hhhh iiii jjjj kkkk llll mmmm GG HHHH IIII JJJJ KKKK LLLL MMMM
nnnn oooo pppp qqqq rrrr ssss tt NNNN OOOO PPPP QQQQ RRRR SSSS TT
tt uuuu vvvv wwww xxxx yyyy zzzz TT UUUU VVVV WWWW XXXX YYYY ZZZZ


EXIT VALUES

  The fold command returns the following values:

  0   All input files were successfully processed.

  1   A usage error occurred.

  2   An input file cannot be opened.  The fold command continues processing
      the other input files specified on the command line.

RELATED INFORMATION

  Commands:  cut(1), expand(1), unexpand(1), paste(1).