| COLCRT(1) | General Commands Manual | COLCRT(1) | 
NAME
 colcrt — filter nroff output for CRT previewing
SYNOPSIS
| colcrt | [-] [-2] [file ...] | 
 
DESCRIPTION
 colcrt 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.
Available options:
- 
-
- 
Suppress all underlining. This option is especially useful for previewing allboxed tables from tbl(1).
- 
-2
- 
Causes 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 -2 option is useful for sending output to the line printer when the output contains superscripts and subscripts which would otherwise be invisible.
 
EXAMPLES
 A typical use of 
colcrt would be
tbl exum2.n | nroff -ms | colcrt - | more
 
HISTORY
 The colcrt command appeared in 3.0BSD.
BUGS
 Should fold underlines onto blanks even with the ‘
-' option so that a true underline character would show.
Can't back up more than 102 lines.
General overstriking is lost; as a special case ‘|' overstruck with ‘-' or underline becomes ‘+'.
Lines are trimmed to 132 characters.
Some provision should be made for processing superscripts and subscripts in documents which are already double-spaced.