1.\" Copyright (c) 1980, 1990 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)colcrt.1 6.7 (Berkeley) 03/14/91 7.\" 8.Dd 9.Dt COLCRT 1 10.Os BSD 3 11.Sh NAME 12.Nm colcrt 13.Nd filter nroff output for CRT previewing 14.Sh SYNOPSIS 15.Nm colcrt 16.Op Fl 17.Op Fl \&2 18.Op Ar 19.Sh DESCRIPTION 20.Nm Colcrt 21provides virtual half-line and reverse line feed sequences 22for terminals without such capability, and on which overstriking 23is destructive. 24Half-line characters and underlining (changed to dashing `\-') 25are placed on new lines in between the normal output lines. 26.Pp 27Available options: 28.Bl -tag -width Ds 29.It Fl 30Suppress all underlining. 31It is especially useful for previewing 32.Em allboxed 33tables from 34.Xr tbl 1 . 35.It Fl 2 36Causes all half-lines to be printed, effectively double spacing the output. 37Normally, a minimal space output format is used which will suppress empty 38lines. 39The program never suppresses two consecutive empty lines, however. 40The 41.Fl 2 42option is useful for sending output to the line printer when the output 43contains superscripts and subscripts which would otherwise be invisible. 44.El 45.Sh EXAMPLES 46A typical use of 47.Nm colcrt 48would be 49.Bd -literal 50tbl exum2.n \&| nroff \-ms \&| colcrt \- \&| more 51.Ed 52.Sh SEE ALSO 53.Xr nroff 1 , 54.Xr troff 1 , 55.Xr col 1 , 56.Xr more 1 , 57.Xr ul 1 58.Sh BUGS 59Should fold underlines onto blanks even with the 60.Ql Fl 61option so that 62a true underline character would show; if we did this, however, 63.Nm colcrt 64wouldn't get rid of 65.Ar cu Ns 'd 66underlining 67completely. 68.Pp 69Can't back up more than 102 lines. 70.Pp 71General overstriking is lost; 72as a special case 73.Ql \&| 74overstruck with 75.Ql \- 76or underline becomes 77.Ql \&+ . 78.Pp 79Lines are trimmed to 132 characters. 80.Pp 81Some provision should be made for processing superscripts and subscripts 82in documents which are already double-spaced. 83.Sh HISTORY 84The 85.Nm 86command appeared in 87.Bx 3.0 . 88