|COLCRT(1)||FreeBSD General Commands Manual||COLCRT(1)|
NAMEcolcrt — filter nroff output for CRT previewing
|colcrt||[ -][ -2][ file ...]|
DESCRIPTIONThe colcrt 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.
The following options are available:
- Suppress all underlining. This option is especially useful for previewing allboxed tables from tbl(1).
- 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 -2 option is useful for sending output to the line printer when the output contains superscripts and subscripts which would otherwise be invisible.
ENVIRONMENTThe LANG, LC_ALL and LC_CTYPE environment variables affect the execution of colcrt as described in environ(7).
EXIT STATUSThe colcrt utility exits 0 on success, and >0 if an error occurs.
EXAMPLESA typical use of colcrt would be
tbl exum2.n | nroff -ms | colcrt - | more
HISTORYThe colcrt command appeared in 3.0BSD.
BUGSShould fold underlines onto blanks even with the ‘ -’ option so that a true underline character would show.
Cannot 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.
Characters that take up more than one column position may not be underlined correctly.
|July 31, 2004||FreeBSD|