COLCRT(1)						    BSD General Commands Manual 						 COLCRT(1)

NAME

     colcrt -- filter nroff output for CRT previewing

SYNOPSIS

     colcrt [-] [-2] [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.

     Available options:

     -	     Suppress all underlining.	This option is especially useful for previewing allboxed tables from tbl(1).

     -2      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.

EXAMPLES

     A typical use of colcrt would be

     tbl exum2.n | nroff -ms | colcrt - | more

SEE ALSO

     nroff(1), troff(1), col(1), more(1), ul(1)

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.

HISTORY

     The colcrt command appeared in 3.0BSD.

3rd Berkeley Distribution					   June 30, 1993					 3rd Berkeley Distribution