col(1)           (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


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   col(1)           (Directory and File Management Utilities)           col(1)


         Discussion and Reference Manual .

   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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