1.\" Copyright (c) 1990, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" Michael Rendell. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. All advertising materials mentioning features or use of this software 16.\" must display the following acknowledgement: 17.\" This product includes software developed by the University of 18.\" California, Berkeley and its contributors. 19.\" 4. Neither the name of the University nor the names of its contributors 20.\" may be used to endorse or promote products derived from this software 21.\" without specific prior written permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" @(#)col.1 8.1 (Berkeley) 6/29/93 36.\" $FreeBSD$ 37.\" 38.Dd June 29, 1993 39.Dt COL 1 40.Os 41.Sh NAME 42.Nm col 43.Nd filter reverse line feeds from input 44.Sh SYNOPSIS 45.Nm 46.Op Fl bfhpx 47.Op Fl l Ar num 48.Sh DESCRIPTION 49.Nm Col 50filters out reverse (and half reverse) line feeds so that the output is 51in the correct order with only forward and half forward line 52feeds, and replaces white-space characters with tabs where possible. 53This can be useful in processing the output of 54.Xr nroff 1 55and 56.Xr tbl 1 . 57.Pp 58.Nm Col 59reads from the standard input and writes to the standard output. 60.Pp 61The options are as follows: 62.Bl -tag -width indent 63.It Fl b 64Do not output any backspaces, printing only the last character 65written to each column position. 66.It Fl f 67Forward half line feeds are permitted (``fine'' mode). 68Normally characters printed on a half line boundary are printed 69on the following line. 70.It Fl h 71Don't output multiple spaces instead of tabs (default). 72.It Fl p 73Force unknown control sequences to be passed through unchanged. 74Normally, 75.Nm 76will filter out any control sequences from the input other than those 77recognized and interpreted by itself, which are listed below. 78.It Fl x 79Output multiple spaces instead of tabs. 80.It Fl l Ar num 81Buffer at least 82.Ar num 83lines in memory. 84By default, 128 lines are buffered. 85.El 86.Pp 87The control sequences for carriage motion that 88.Nm 89understands and their decimal values are listed in the following 90table: 91.Pp 92.Bl -tag -width "carriage return" -compact 93.It ESC\-7 94reverse line feed (escape then 7) 95.It ESC\-8 96half reverse line feed (escape then 8) 97.It ESC\-9 98half forward line feed (escape then 9) 99.It backspace 100moves back one column (8); ignored in the first column 101.It carriage return 102(13) 103.It newline 104forward line feed (10); also does carriage return 105.It shift in 106shift to normal character set (15) 107.It shift out 108shift to alternate character set (14) 109.It space 110moves forward one column (32) 111.It tab 112moves forward to next tab stop (9) 113.It vertical tab 114reverse line feed (11) 115.El 116.Pp 117All unrecognized control characters and escape sequences are 118discarded. 119.Pp 120.Nm Col 121keeps track of the character set as characters are read and makes 122sure the character set is correct when they are output. 123.Pp 124If the input attempts to back up to the last flushed line, 125.Nm 126will display a warning message. 127.Sh SEE ALSO 128.Xr expand 1 , 129.Xr nroff 1 , 130.Xr tbl 1 131.Sh HISTORY 132A 133.Nm 134command 135appeared in 136.At v6 . 137