colcrt
COLCRT(1) User Commands COLCRT(1)
NAME
colcrt - filter nroff output for CRT previewing
SYNOPSIS
colcrt [options] [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.
OPTIONS
-, --no-underlining
Suppress all underlining. This option is especially useful for
previewing allboxed tables from tbl(1).
-2, --half-lines
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.
-V, --version
Display version information and exit.
-h, --help
Display help text and exit.
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.
EXAMPLES
A typical use of colcrt would be:
tbl exum2.n | nroff -ms | colcrt - | more
SEE ALSO
col(1), more(1), nroff(1), troff(1), ul(1)
REPORTING BUGS
For bug reports, use the issue tracker at
https://github.com/karelzak/util-linux/issues.
AVAILABILITY
The colcrt command is part of the util-linux package which can be
downloaded from Linux Kernel Archive
<https://www.kernel.org/pub/linux/utils/util-linux/>.
util-linux 2.37.2 2021-06-02 COLCRT(1)
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