32v 1m col

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COL(1) UNIX Programmer's Manual COL(1)


NAME

    col - filter reverse line feeds

SYNOPSIS

    col [-bfx]

DESCRIPTION

    _C_o_l reads the standard input and writes the standard output.
    It performs the line overlays implied by reverse line feeds
    (ESC-7 in ASCII) and by forward and reverse half line feeds
    (ESC-9 and ESC-8).  _C_o_l is particularly useful for filtering
    multicolumn output made with the `.rt' command of _n_r_o_f_f and
    output resulting from use of the _t_b_l(1) preprocessor.
    Although _c_o_l accepts half line motions in its input, it nor-
    mally 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 _c_o_l may contain
    forward half line feeds (ESC-9), but will still never con-
    tain either kind of reverse line motion.
    If the -b option is given, _c_o_l assumes that the output dev-
    ice in use is not capable of backspacing.  In this case, if
    several characters are to appear in the same place, only the
    last one read will be taken.
    The control characters SO (ASCII code 017), and SI (016) are
    assumed to start and end text in an alternate character set.
    The character set (primary or alternate) associated with
    each printing character read is remembered; on output, SO
    and SI characters are generated where necessary to maintain
    the correct treatment of each character.
    _C_o_l normally converts white space to tabs to shorten print-
    ing time.  If the -x option is given, this conversion is
    suppressed.
    All control characters are removed from the input except
    space, backspace, tab, return, newline, ESC (033) followed
    by one of 7, 8, 9, SI, SO, and VT (013).  This last charac-
    ter is an alternate form of full reverse line feed, for com-
    patibility with some other hardware conventions.  All other
    non-printing characters are ignored.

SEE ALSO

    troff(1), tbl(1), greek(1)

BUGS

    Can't back up more than 128 lines.
    No more than 800 characters, including backspaces, on a
    line.