{
    "mode": "man",
    "parameter": "colcrt",
    "section": "1",
    "url": "https://www.chedong.com/phpMan.php/man/colcrt/1/json",
    "generated": "2026-06-13T04:33:30Z",
    "synopsis": "colcrt [options] [file ...]",
    "sections": {
        "NAME": {
            "content": "colcrt - filter nroff output for CRT previewing\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "colcrt [options] [file ...]\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "colcrt provides virtual half-line and reverse line feed sequences for terminals without such\ncapability, and on which overstriking is destructive. Half-line characters and underlining\n(changed to dashing `-') are placed on new lines in between the normal output lines.\n",
            "subsections": []
        },
        "OPTIONS": {
            "content": "-, --no-underlining\nSuppress all underlining. This option is especially useful for previewing allboxed tables\nfrom tbl(1).\n",
            "subsections": [
                {
                    "name": "-2 --half-lines",
                    "content": "Causes all half-lines to be printed, effectively double spacing the output. Normally, a\nminimal space output format is used which will suppress empty lines. The program never\nsuppresses two consecutive empty lines, however. The -2 option is useful for sending\noutput to the line printer when the output contains superscripts and subscripts which\nwould otherwise be invisible.\n",
                    "flag": "-2",
                    "long": "--half-lines"
                },
                {
                    "name": "-V --version",
                    "content": "Display version information and exit.\n",
                    "flag": "-V",
                    "long": "--version"
                },
                {
                    "name": "-h --help",
                    "content": "Display help text and exit.\n",
                    "flag": "-h",
                    "long": "--help"
                }
            ]
        },
        "HISTORY": {
            "content": "The colcrt command appeared in 3.0BSD.\n",
            "subsections": []
        },
        "BUGS": {
            "content": "Should fold underlines onto blanks even with the '-' option so that a true underline\ncharacter would show.\n\nCan’t back up more than 102 lines.\n\nGeneral overstriking is lost; as a special case '|' overstruck with '-' or underline becomes\n'+'.\n\nLines are trimmed to 132 characters.\n\nSome provision should be made for processing superscripts and subscripts in documents which\nare already double-spaced.\n",
            "subsections": []
        },
        "EXAMPLES": {
            "content": "A typical use of colcrt would be:\n\ntbl exum2.n | nroff -ms | colcrt - | more\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "col(1), more(1), nroff(1), troff(1), ul(1)\n",
            "subsections": []
        },
        "REPORTING BUGS": {
            "content": "For bug reports, use the issue tracker at https://github.com/karelzak/util-linux/issues.\n",
            "subsections": []
        },
        "AVAILABILITY": {
            "content": "The colcrt command is part of the util-linux package which can be downloaded from Linux\nKernel Archive <https://www.kernel.org/pub/linux/utils/util-linux/>.\n\n\n\nutil-linux 2.37.2                            2021-06-02                                    COLCRT(1)",
            "subsections": []
        }
    },
    "summary": "colcrt - filter nroff output for CRT previewing",
    "flags": [
        {
            "flag": "-2",
            "long": "--half-lines",
            "arg": null,
            "description": "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."
        },
        {
            "flag": "-V",
            "long": "--version",
            "arg": null,
            "description": "Display version information and exit."
        },
        {
            "flag": "-h",
            "long": "--help",
            "arg": null,
            "description": "Display help text and exit."
        }
    ],
    "examples": [
        "A typical use of colcrt would be:",
        "tbl exum2.n | nroff -ms | colcrt - | more"
    ],
    "see_also": [
        {
            "name": "col",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/col/1/json"
        },
        {
            "name": "more",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/more/1/json"
        },
        {
            "name": "nroff",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/nroff/1/json"
        },
        {
            "name": "troff",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/troff/1/json"
        },
        {
            "name": "ul",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/ul/1/json"
        }
    ]
}