nroff output for CRT previewing
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
The following options are available:
- Suppress all underlining. This option is especially useful
for previewing allboxed tables from
- 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.
environment variables affect the
execution of colcrt
as described in
utility exits 0 on success,
and >0 if an error occurs.
A typical use of colcrt
tbl exum2.n | nroff -ms | colcrt - | more
command appeared in
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