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fold(1)                          User Commands                         fold(1)



NAME
       fold - filter for folding lines

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

DESCRIPTION
       The fold utility is a filter that will fold lines from its input files,
       breaking the lines to have a maximum  of  width  column  positions  (or
       bytes,  if  the  -b  option  is specified). Lines will be broken by the
       insertion of a NEWLINE character such that each output  line  (referred
       to  later  in  this section as a segment) is the maximum width possible
       that does not exceed the  specified  number  of  column  positions  (or
       bytes).  A  line  will  not be broken in the middle of a character. The
       behavior is undefined if width is less than the number of  columns  any
       single character in the input would occupy.

       If the CARRIAGE-RETURN, BACKSPACE, or TAB characters are encountered in
       the input, and the -b option is not specified,  they  will  be  treated
       specially:

       BACKSPACE               The  current count of line width will be decre-
                               mented by one, although the  count  never  will
                               become negative. fold will not insert a NEWLINE
                               character  immediately  before  or  after   any
                               BACKSPACE character.



       CARRIAGE-RETURN         The  current count of line width will be set to
                               0. fold will not  insert  a  NEWLINE  character
                               immediately before or after any CARRIAGE-RETURN
                               character.



       TAB                     Each TAB character encountered will advance the
                               column  position  pointer to the next tab stop.
                               Tab stops will be at  each  column  position  n
                               such that n modulo 8 equals 1.



OPTIONS
       The following options are supported:

       -b              Counts width in bytes rather than column positions.



       -s              If  a  segment  of  a  line  contains a blank character
                       within the first width  column  positions  (or  bytes),
                       breaks  the  line  after  the last such blank character
                       meeting the width constraints. If  there  is  no  blank
                       character  meeting the requirements, the -s option will
                       have no effect for that output  segment  of  the  input
                       line.



       -w width|-width Specifies  the maximum line length, in column positions
                       (or bytes if -b is specified). If width is not a  posi-
                       tive  decimal number, an error is returned. The default
                       value is 80.



OPERANDS
       The following operand is supported:

       file     A path name of a text file to be folded. If no  file  operands
                are specified, the standard input will be used.



EXAMPLES
       Example 1: Submitting a file of possibly long lines to the line printer

       An example invocation that submits a file of possibly long lines to the
       line printer (under the assumption that the user knows the  line  width
       of the printer to be assigned by lp(1)):

       example% fold -w 132 bigfile | lp

ENVIRONMENT VARIABLES
       See  environ(5) for descriptions of the following environment variables
       that affect the execution of fold: LANG, LC_ALL, LC_CTYPE, LC_MESSAGES,
       and NLSPATH.

EXIT STATUS
       The following exit values are returned:

       0        All input files were processed successfully.



       >>0       An error occurred.



ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:


       tab()     allbox;     cw(2.750000i)|    cw(2.750000i)    lw(2.750000i)|
       lw(2.750000i).   ATTRIBUTE  TYPEATTRIBUTE   VALUE   AvailabilitySUNWcsu
       CSIenabled Interface StabilityStandard


SEE ALSO
       cut(1), pr(1), attributes(5), environ(5), standards(5)

NOTES
       fold  and  cut(1)  can  be  used to create text files out of files with
       arbitrary line lengths. fold should be used when the contents  of  long
       lines need to be kept contiguous. cut should be used when the number of
       lines (or records) needs to remain constant.

       fold is frequently used to send text files to line printers that  trun-
       cate,  rather  than fold, lines wider than the printer is able to print
       (usually 80 or 132 column positions).

       fold may not work correctly if underlining is present.



SunOS 5.10                        1 Feb 1995                           fold(1)