– filter nroff output for CRT previewing
provides virtual half-line and reverse line feed sequences
for terminals without such capability, and on which overstriking
Half-line characters and underlining (changed to dashing `-‘)
are placed on new lines in between the normal output lines.
option is useful for sending output to the line printer when the output
contains superscripts and subscripts which would otherwise be invisible.
A typical use of
tbl exum2.n | nroff -ms | colcrt – | more
Should fold underlines onto blanks even with the
a true underline character would show.
Can’t back up more than 102 lines.
General overstriking is lost;
as a special case
or underline becomes
Lines are trimmed to 132 characters.
command appeared in
The colcrt command is part of the util-linux-ng package and is available from