NAME
colcrt —
filter nroff output for CRT
previewing
SYNOPSIS
colcrt |
[-] [-2]
[file ...] |
DESCRIPTION
Thecolcrt 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).
-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
-2option is useful for sending output to the line printer when the output contains superscripts and subscripts which would otherwise be invisible.
ENVIRONMENT
The LANG, LC_ALL
and LC_CTYPE environment variables affect the
execution of colcrt as described in
environ(7).
EXIT STATUS
The colcrt utility exits 0 on
success, and >0 if an error occurs.
EXAMPLES
A typical use of colcrt would be
tbl exum2.n | nroff -ms | colcrt - | more
SEE ALSO
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.
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.