.\" Copyright (c) 1980, 1990, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)colcrt.1 8.1 (Berkeley) 6/30/93 .\" $FreeBSD: src/usr.bin/colcrt/colcrt.1,v 1.13 2004/07/31 06:22:01 tjr Exp $ .\" .Dd July 31, 2004 .Dt COLCRT 1 .Os .Sh NAME .Nm colcrt .Nd filter nroff output for CRT previewing .Sh SYNOPSIS .Nm .Op Fl .Op Fl \&2 .Op Ar .Sh DESCRIPTION The .Nm utility provides virtual half-line and reverse line feed sequences for terminals without such capability, and on which overstriking is destructive. Half-line characters and underlining (changed to dashing `\-') are placed on new lines in between the normal output lines. .Pp The following options are available: .Bl -tag -width indent .It Fl Suppress all underlining. This option is especially useful for previewing .Em allboxed tables from .Xr tbl 1 . .It Fl 2 Cause all half-lines to be printed, effectively double spacing the output. Normally, a minimal space output format is used which will suppress empty lines. The program never suppresses two consecutive empty lines, however. The .Fl 2 option is useful for sending output to the line printer when the output contains superscripts and subscripts which would otherwise be invisible. .El .Sh ENVIRONMENT The .Ev LANG , LC_ALL and .Ev LC_CTYPE environment variables affect the execution of .Nm as described in .Xr environ 7 . .Sh EXAMPLES A typical use of .Nm would be .Bd -literal tbl exum2.n \&| nroff \-ms \&| colcrt \- \&| more .Ed .Sh DIAGNOSTICS .Ex -std .Sh SEE ALSO .Xr col 1 , .Xr more 1 , .Xr nroff 1 , .Xr troff 1 , .Xr ul 1 .Sh BUGS Should fold underlines onto blanks even with the .Sq Fl option so that a true underline character would show. .Pp Can't back up more than 102 lines. .Pp General overstriking is lost; as a special case .Ql \&| overstruck with .Ql \- or underline becomes .Ql \&+ . .Pp Lines are trimmed to 132 characters. .Pp Some provision should be made for processing superscripts and subscripts in documents which are already double-spaced. .Pp Characters that take up more than one column position may not be underlined correctly. .Sh HISTORY The .Nm command appeared in .Bx 3.0 .