filter nroff output for CRT previewing
see also :
col - more - nroff - troff - ul
[-2] [file ...]
add an example, a script, a trick and tips
A typical use of colcrt would be
tbl exum2.n | nroff -ms | colcrt - | more
splitting_command="man $manpage | colcrt - |
# - `colcrt` is a standard BSD utility
that strip out screen control
man 3 $1 2> /dev/null | colcrt \
| grep "#include
| sed -e 's,#include,,' -e 's,<,,'
-e 's,>,,' -e 's,[
| sort | uniq
The colcrt 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.
options are available:
underlining. This option is especially useful for previewing
allboxed tables from tbl(1).
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.
The LANG, LC_ALL and LC_CTYPE environment variables affect the
execution of colcrt as described in environ(7).
The colcrt utility exits 0 on success, and >0
if an error occurs.
Should fold underlines onto
blanks even with the ’-’ option so
that a true underline character would show.
Cannot back up
more than 102 lines.
overstriking is lost; as a special case ’|’
overstruck with ’-’ or underline becomes
trimmed to 132 characters.
should be made for processing superscripts and subscripts in
documents which are already double-spaced.
take up more than one column position may not be underlined
July 31, 2004 BSD
The colcrt command
appeared in 3.0BSD.
col , more , nroff ,
troff , ul