COLCRT(1)                            BSD                             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 for which overstriking is
     destructive.  Half-line characters and underlines (changed to dashes `-')
     are placed on new lines between the normal output lines.

     Normally, colcrt uses a minimal space output format that suppresses empty
     lines.  However, the program never suppresses two consecutive empty
     lines.

OPTIONS
     -         Suppress all underlining.  This option is especially useful for
               previewing tables that use tbl's allbox option.

     -2        Print all half-lines, effectively double-spacing the output.
               The -2 option is useful for sending output that contains
               superscripts and subscripts to the line printer (these
               characters are otherwise invisible).

EXAMPLE
     The following example shows a  typical use of colcrt:

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

BUGS
     colcrt doesn't fold underlines onto blanks even with the - option; true
     underline characters don't show.

     colcrt can't back up more than 102 lines.

     General overstriking is lost. As a special case, | overstruck with a dash
     (-) or underline becomes a plus sign (+).

     Lines are trimmed to 132 characters.

     No provision is made for processing superscripts and subscripts in
     documents that are already double-spaced.

SEE ALSO
     col(1), more(1), nroff(1), troff(1), tbl(1), ul(1)