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 6.5 (Berkeley) 07/05/90 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.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 27.Tp Fl 28Suppress all underlining. 29It is especially useful for previewing 30.Ar allboxed 31tables from 32.Xr tbl 1 . 33.Pp 34.Tp Fl 2 35Causes all half-lines to be printed, effectively double spacing the output. 36Normally, a minimal space output format is used which will suppress empty 37lines. 38The program never suppresses two consecutive empty lines, however. 39The 40.Fl 2 41option is useful for sending output to the line printer when the output 42contains superscripts and subscripts which would otherwise be invisible. 43.Tp 44.Pp 45A typical use of 46.Nm colcrt 47would be 48.Pp 49.Dl tbl exum2.n \&| nroff \-ms \&| colcrt \- \&| more 50.Sh SEE ALSO 51.Xr nroff 1 , 52.Xr troff 1 , 53.Xr col 1 , 54.Xr more 1 , 55.Xr ul 1 56.Sh HISTORY 57Appeared in 3 BSD. 58.Sh BUGS 59Should fold underlines onto blanks even with the 60.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'd 66underlining 67completely. 68.Pp 69Can't back up more than 102 lines. 70.Pp 71General overstriking is lost; 72as a special case `\&|' overstruck with `\-' or underline becomes `+'. 73.Pp 74Lines are trimmed to 132 characters. 75.Pp 76Some provision should be made for processing superscripts and subscripts 77in documents which are already double-spaced. 78