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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.

STANDARDS

  Interfaces documented	on this	reference page conform to industry standards
  as follows:

  fold:	 XCU5.0

  Refer	to the standards(5) reference page for more information	about indus-
  try standards	and associated tags.

OPTIONS

  -b  Specifies	that width be counted in bytes rather than in column posi-
      tions.  Using the	-b option 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 option 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 option 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.

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 option
  is specified).  The fold command wraps lines by inserting a newline charac-
  ter into the output so that each output line is the maximum column posi-
  tions	or bytes specified.  A line cannot be broken in	the middle of a	char-
  acter.

  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 <&lt;backspace>&gt;, <&lt;tab>&gt;, or	<&lt;carriage return>&gt; characters are encountered
  in the input,	and the	-b option is not specified, these characters are
  treated specially:

  <&lt;backspace>&gt;
      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.

  <&lt;tab>&gt;
      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.

  <&lt;carriage-return>&gt;
      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.

  [Tru64 UNIX]	The fold command possibly affects underlining in a file.

EXIT STATUS

  The fold command returns the following values:

  0   All input	files were successfully	processed.

  1   [Tru64 UNIX]  A usage error occurred.

  2   [Tru64 UNIX]  An input file cannot be opened.  The fold command contin-
      ues processing the other input files specified on	the command line.

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 >&gt; az2; fold -w 32 AZ >&gt; 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

ENVIRONMENT VARIABLES

  The following	environment variables affect the execution of fold:

  LANG
      Provides a default value for the internationalization variables that
      are unset	or null. If LANG is unset or null, the corresponding value
      from the default locale is used.	If any of the internationalization
      variables	contain	an invalid setting, the	utility	behaves	as if none of
      the variables had	been defined.

  LC_ALL
      If set to	a non-empty string value, overrides the	values of all the
      other internationalization variables.

  LC_CTYPE
      Determines the locale for	the interpretation of sequences	of bytes of
      text data	as characters (for example, single-byte	as opposed to multi-
      byte characters in arguments) and	for the	determination of the width in
      column positions each character would occupy on a	constant-width font
      output device.

  LC_MESSAGES
      Determines the locale for	the format and contents	of diagnostic mes-
      sages written to standard	error.

  NLSPATH
      Determines the location of message catalogues for	the processing of
      LC_MESSAGES.

SEE ALSO

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

  Standards:  standards(5)