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. 

The optional − suppresses all underlining.  It is especially useful for previewing allboxed tables from tbl(1).

The option −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. 

A typical use of colcrt would be

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

SEE ALSO

nroff/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; if we did this, however, colcrt wouldn’t get rid of cu’d underlining completely. 

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. 

September 02, 1992