col(1)      UNIX System V(Directory and File Management Utilities)       col(1)


NAME
      col - filter reverse line-feeds

SYNOPSIS
      col [-b] [-f] [-x] [-p]

DESCRIPTION
      col reads from the standard input and writes onto the standard output.
      It performs the line overlays implied by reverse line feeds (ASCII code
      ESC-7), and by forward and reverse half-line-feeds (ESC-9 and ESC-8).
      col is particularly useful for filtering multicolumn output made with the
      .rt command of nroff and output resulting from use of the tbl(1)
      preprocessor.

      If the -b option is given, col assumes that the output device in use is
      not capable of backspacing.  In this case, if two or more characters are
      to appear in the same place, only the last one read will be output.

      Although col accepts half-line motions in its input, it normally does not
      emit them on output.  Instead, text that would appear between lines is
      moved to the next lower full-line boundary.  This treatment can be
      suppressed by the -f (fine) option; in this case, the output from col may
      contain forward half-line-feeds (ESC-9), but will still never contain
      either kind of reverse line motion.

      Unless the -x option is given, col will convert white space to tabs on
      output wherever possible to shorten printing time.

      The ASCII control characters SO (\017) and SI (\016) are assumed by col
      to start and end text in an alternate character set.  The character set
      to which each input character belongs is remembered, and on output SI and
      SO characters are generated as appropriate to ensure that each character
      is printed in the correct character set.

      On input, the only control characters accepted are space, backspace, tab,
      return, new-line, SI, SO, VT (\013), and ESC followed by 7, 8, or 9.  The
      VT character is an alternate form of full reverse line-feed, included for
      compatibility with some earlier programs of this type.  All other non-
      printing characters are ignored.

      Normally, col will ignore any escape sequences unknown to it that are
      found in its input; the -p option may be used to cause col to output
      these sequences as regular characters, subject to overprinting from
      reverse line motions.  The use of this option is highly discouraged
      unless the user is fully aware of the textual position of the escape
      sequences.

SEE ALSO
      ascii(5)
      nroff(1), tbl(1) in the DOCUMENTER'S WORKBENCH Software Technical
      Discussion and Reference Manual .



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col(1)      UNIX System V(Directory and File Management Utilities)       col(1)


NOTES
      The input format accepted by col matches the output produced by nroff
      with either the -T37 or -Tlp options.  Use -T37 (and the -f option of
      col) if the ultimate disposition of the output of col will be a device
      that can interpret half-line motions, and -Tlp otherwise.

      col cannot back up more than 128 lines or handle more than 800 characters
      per line.

      Local vertical motions that would result in backing up over the first
      line of the document are ignored.  As a result, the first line must not
      have any superscripts.










































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