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. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)col.1 8.1 (Berkeley) 6/29/93 32.\" $FreeBSD: src/usr.bin/col/col.1,v 1.4.2.7 2002/07/15 04:32:27 keramida Exp $ 33.\" $DragonFly: src/usr.bin/col/col.1,v 1.2 2003/06/17 04:29:25 dillon Exp $ 34.\" 35.Dd June 29, 1993 36.Dt COL 1 37.Os 38.Sh NAME 39.Nm col 40.Nd filter reverse line feeds from input 41.Sh SYNOPSIS 42.Nm 43.Op Fl bfhpx 44.Op Fl l Ar num 45.Sh DESCRIPTION 46The 47.Nm 48utility filters out reverse (and half reverse) line feeds so that the output is 49in the correct order with only forward and half forward line 50feeds, and replaces white-space characters with tabs where possible. 51This can be useful in processing the output of 52.Xr nroff 1 53and 54.Xr tbl 1 . 55.Pp 56The 57.Nm 58utility reads from the standard input and writes to the standard output. 59.Pp 60The options are as follows: 61.Bl -tag -width indent 62.It Fl b 63Do not output any backspaces, printing only the last character 64written to each column position. 65.It Fl f 66Forward half line feeds are permitted (``fine'' mode). 67Normally characters printed on a half line boundary are printed 68on the following line. 69.It Fl h 70Don't output multiple spaces instead of tabs (default). 71.It Fl l Ar num 72Buffer at least 73.Ar num 74lines in memory. 75By default, 128 lines are buffered. 76.It Fl p 77Force unknown control sequences to be passed through unchanged. 78Normally, 79.Nm 80will filter out any control sequences from the input other than those 81recognized and interpreted by itself, which are listed below. 82.It Fl x 83Output multiple spaces instead of tabs. 84.El 85.Pp 86The control sequences for carriage motion that 87.Nm 88understands and their decimal values are listed in the following 89table: 90.Pp 91.Bl -tag -width "carriage return" -compact 92.It ESC\-7 93reverse line feed (escape then 7) 94.It ESC\-8 95half reverse line feed (escape then 8) 96.It ESC\-9 97half forward line feed (escape then 9) 98.It backspace 99moves back one column (8); ignored in the first column 100.It carriage return 101(13) 102.It newline 103forward line feed (10); also does carriage return 104.It shift in 105shift to normal character set (15) 106.It shift out 107shift to alternate character set (14) 108.It space 109moves forward one column (32) 110.It tab 111moves forward to next tab stop (9) 112.It vertical tab 113reverse line feed (11) 114.El 115.Pp 116All unrecognized control characters and escape sequences are 117discarded. 118.Pp 119The 120.Nm 121utility keeps 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 STANDARDS 132The 133.Nm 134utility conforms to 135.St -susv2 . 136.Sh HISTORY 137A 138.Nm 139command 140appeared in 141.At v6 . 142