filter nroff output for CRT previewing
colcrt [options] [file...]
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.
- -, --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.
The colcrt command appeared in 3.0BSD.
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.
A typical use of colcrt would be:
tbl exum2.n | nroff -ms | colcrt - | more
The colcrt command is part of the util-linux package and is available from Linux Kernel Archive.