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

     colcrt -- filter nroff output for CRT previewing

     colcrt [-] [-2] [file ...]

     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.

     The following options are available:

     -       Suppress all underlining.  This option is especially useful for previewing allboxed tables from

     -2      Cause 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 invisi-ble. invisible.

     The LANG, LC_ALL and LC_CTYPE environment variables affect the execution of colcrt as described in

     A typical use of colcrt would be

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

     The colcrt utility exits 0 on success, and >0 if an error occurs.

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

     Should fold underlines onto blanks even with the `-' option so that a true underline character would

     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

     Characters that take up more than one column position may not be underlined correctly.

     The colcrt command appeared in 3.0BSD.

BSD                              July 31, 2004                             BSD

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