1COLCRT(1)                        User Commands                       COLCRT(1)
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NAME

6       colcrt - filter nroff output for CRT previewing
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SYNOPSIS

9       colcrt [options] [file...]
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DESCRIPTION

12       colcrt  provides  virtual half-line and reverse line feed sequences for
13       terminals  without  such  capability,  and  on  which  overstriking  is
14       destructive.   Half-line characters and underlining (changed to dashing
15       `-') are placed on new lines in between the normal output lines.
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OPTIONS

18       -, --no-underlining
19              Suppress all underlining.  This option is especially useful  for
20              previewing allboxed tables from tbl(1).
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22       -2, --half-lines
23              Causes  all half-lines to be printed, effectively double spacing
24              the output.  Normally, a minimal space  output  format  is  used
25              which  will  suppress empty lines.  The program never suppresses
26              two consecutive empty lines, however.  The -2 option  is  useful
27              for  sending output to the line printer when the output contains
28              superscripts and subscripts which would otherwise be invisible.
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30       -V, --version
31              Display version information and exit.
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33       -h, --help
34              Display help text and exit.
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HISTORY

37       The colcrt command appeared in 3.0BSD.
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BUGS

40       Should fold underlines onto blanks even with the '-' option so  that  a
41       true underline character would show.
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43       Can't back up more than 102 lines.
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45       General overstriking is lost; as a special case '|' overstruck with '-'
46       or underline becomes '+'.
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48       Lines are trimmed to 132 characters.
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50       Some provision should be made  for  processing  superscripts  and  sub‐
51       scripts in documents which are already double-spaced.
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EXAMPLES

54       A typical use of colcrt would be:
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56              tbl exum2.n | nroff -ms | colcrt - | more
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SEE ALSO

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

62       The  colcrt  command is part of the util-linux package and is available
63       from Linux Kernel Archive ⟨https://www.kernel.org/pub/linux/utils/util-
64       linux/⟩.
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68util-linux                      September 2011                       COLCRT(1)
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