MAN2HTML(1)

NAME
man2html - convert UNIX nroff(1) manual pages to HTML format

SYNOPSIS

Typical Usage:

< infile > outfile

man topic | man2html > outfile

DESCRIPTION
The man2html filter reads formatted nroff text from standard input (stdin) and writes a HTML document to standard output (stdout).

The formatted nroff output is surrounded with <PRE> tags with the following exceptions/additions:
    Section heads are wrapped in HTML header tags. See the SECTION HEAD MAP FILE section below for additional information. The -noheads option can be used to disable this feature. Bold words designated by a "<char><bs><char>" sequences are wrapped in <B> tags (or the element specified via the -belem option). Underlined words designated by a "_<bs><char>" sequences are wrapped in <I> tags (or the element specified via the -uelem option). Italicized and bold section heads designated by a "_<bs><char><bs><char>" sequences are detected if the option -mixsecs is given.

OPTIONS

-aliases file
    Gives man2html a list of manpage aliases, i.e., alternate names for manual pages. The file contains one alias per line, followed by the actual manual page name. Man2html will link the reference for the alias to the actual manual page.

-bare
    This option will eliminate HTML <HEAD> and <BODY> tags from the output. This is useful when you wish to incorporate the output into another HTML document.

-belem name
    Use name as the name of the element to wrap overstriken characters. The default is B.

-botm lines
    The lines argument specifies the number of lines representing the bottom margin of the formatted nroff input. The line count includes any running footers. The default value is 7.

-cgiurl string
    The string argument specifies a template URL for creating links to other manpages. See the LINKING TO MANPAGES section below for additional information.

-cgiurlexp expr
    The expr argument specifies a Perl expression evaluting to a URL for creating links to other manpages. See the LINKING TO MANPAGES section below for additional information.

-compress
    Compress consecutive blank lines into a single line.

-externs file
    Tell man2html to not attempt to link to the manual pages listed in the file.

-headmap mapfile
    The mapfile argument is read to determine which HTML header tags are to be used for various section heading in the manpage. See the SECTION HEAD MAP FILE section below for information on the format of the map file.

-help
    Print out a short usage message and then exit immediately.

-index
    Write an un-numbered list of headers at the end of the output HTML, which can be used as-is, or post-processed to make that list an HTML “nav” area that can be manipulated with CSS.

-k  Process input resulting from a manpage keyword search (man -k). See the KEYWORD SEARCH section below for additional information.

-leftm chars
    The chars argument specifies the width of the number of characters making up the left margin of the formatted nroff input. The default value is 0.

-leftside file
    Man2html detects references to other manual pages by manpage name (a word, possibly with embedded “-”) in bold font, followed by a section number in parentheses. If the manpage name is split by nroff's hyphenation, man2html can be confused, because it cannot tell whether a “-” at the end of the line is part of a manpage name, or just the hyphenation marker.

    The -leftside option allows you to tell man2html about these special cases, using a file containing the left-side of hyphenated manpage names. If the option is not given, man2html uses a short fallback: "apt", "cvs", "git", "sccs' and "sysv".

-mixsecs
    enables checking for section heads which combine italics (underline) and bold (overstrike).

-nodepage
    By default, man2html merges multi-page formatted nroff into a single page. This option may be used to disable depagination, causing running headers and footers in the formatted nroff input to be carried over into the HTML output.

-noheads
    By default, man2html wraps section heads in HTML header tags. See the SECTION HEAD MAP FILE section below for additional information. This option may be specified to disabled this feature.

-pgsize lines
    The lines argument specifies the number of lines making up the page size (length) of the formatted nroff input. The default value is 66.

-seealso
    If the -cgiurl option has been specified, then this option restricts the creation of links to other manual pages to the SEE ALSO section only.

-solaris
    If the -k option has been specified, then this option modifies its operation to process the alternate manual page keyword search format produced by the man(1) utility on systems running Solaris. See the KEYWORD SEARCH section below for additional information.

-sun
    Do not require a section head to have bold overstriking in the formatted nroff input. The option is called sun because it was on a Sun workstation that section heads in manpages were found to not be overstruck.

-title string
    By default, man2html does not generate a HTML title (<TITLE>). This option sets the title of the HTML output to the specified string.

-toc
    Generate IDs compatible with HTML::Toc, which is used to produce a separate table of contents file. The IDs embedded in HTML header-tags, e.g., “<h3>” will have a “-toc” suffix.

-topm lines
    The lines argument specifies number number of lines representing the top margin of the formatted nroff input. The line count includes any running headers. The default value is 7.

-uelem name
    Use name as the name of the element to wrap underscored characters. The default is I.

SECTION HEAD MAP FILE
The -headmap option may be used to customize which HTML header tags, <H1> ... <H6>, are used in manpage section headings. Normally, man2html treats lines that are flush to the left margin (-leftm), and contain overstriking (overstrike check is canceled with the -sun option), as section heads. However, you can augment/override what HTML header tags are used for any given section head.

In order to write a section head map file, you will need to know about perl(1) associative arrays. You do not need to be an expert in perl to write a map file, however, having knowledge of perl allows you to be more clever.

  Augmenting the Default Map
To add to the default mapping defined by man2html, your map file will contain lines with the following syntax:

$SectionHead{'<section head text>'} = '<html header tag>';

where

<section head text>
    is the text of the manpage section head. For example: SYNOPSIS or DESCRIPTION.

<html header tag>
    is the HTML header tag to wrap the section head in. Legal values are: <H1>, <H2>, <H3>, <H4>, <H5>, <H6>.

  Overriding the Default Map
To override the default mapping with your own, then your map file will have the following syntax:

    %SectionHead = (
             '<section head text>', '<html header tag>',
             '<section head text>', '<html header tag>',
             # ... More section head/tag pairs
             '<section head text>', '<html header tag>',
    );

  The Default Map
As of this writing, this is the default map used by man2html:

    %SectionHead = (
        '\S.*OPTIONS.*'             => '<H2>',
        'AUTHORS?'                  => '<H2>',
        'BUGS'                      => '<H2>',
        'COMPATIBILITY'             => '<H2>',
        'DEPENDENCIES'              => '<H2>',
        'DESCRIPTION'               => '<H2>',
        'DIAGNOSTICS'               => '<H2>',
        'ENVIRONMENT'               => '<H2>',
        'ERRORS'                    => '<H2>',
        'EXAMPLES'                  => '<H2>',
        'EXTERNAL INFLUENCES'       => '<H2>',
        'FILES'                     => '<H2>',
        'LIMITATIONS'               => '<H2>',
        'NAME'                      => '<H2>',
        'NOTES?'                    => '<H2>',
        'OPTIONS'                   => '<H2>',
        'REFERENCES'                => '<H2>',
        'RETURN VALUE'              => '<H2>',
        'SECTION.*:'                => '<H2>',
        'SEE ALSO'                  => '<H2>',
        'STANDARDS CONFORMANCE'     => '<H2>',
        'STYLE CONVENTION'          => '<H2>',
        'SYNOPSIS'                  => '<H2>',
        'SYNTAX'                    => '<H2>',
        'WARNINGS'                  => '<H2>',
        '\s+Section.*:'             => '<H3>',
    );
    $HeadFallback = '<H2>';  # Fallback tag if above is not found.

Check the perl source code of man2html for the latest default mapping.

You can reassign the $HeadFallback variable to a different value if you choose. This value is used as the header tag of a section head if no matches are found in the %SectionHead map.

  Using Regular Expressions
You may have noticed unusual characters in the default map file, such as "\s" or "*". The man2html utility actual treats the <section head text> as a perl regular expression. If you are comfortable with perl regular expressions, then you have their full power to use in your map file.

Caution: The man2html utility already anchors the regular expression to the beginning of the line with left margin spacing specified by the -leftm option. Therefore, do not use the “^” character to anchor your regular expression to the beginning. However, you may end your expression with a “$” to anchor it to the end of the line.

Since the <section head text> is actually a regular expression, you will have to be careful of special characters if you want them to be treated literally. Any of the characters `[ ] ( ) . ^ { } $ * ? + \ |' should be escaped by prefixing them by the “\” character if you want perl to treat them "as is".

Caution: One should use single quotes instead of double quotes to delimit <section head text>. This will preserve any “\” characters for character escaping or when the “\” is used for special perl character matching sequences (e.g., \s, \w, \S).

  Other Tid-bits
Comments can be inserted in the map file by using the '#' character. Anything after, and including, the '#' character is ignored, up to the end of line.

You might be thinking that the above is quite-a-bit-of-stuff just for doing manpage section heads. However, you will be surprised how much better the HTML output looks with header tags, even though, everything else is in a <PRE> tag.

LINKING TO MANPAGES
The man2html utility allows the ability to link to other manpage references. If the -cgiurl option is specified, man2html will create anchors that link to other manpages.

The URL entered with the -cgiurl option is actually a template that determines the actual URL used to link to other manpages. The following variables are defined during run time that may be used in the template string:

    $title
        The title of the manual page referenced.

    $section
        The section number of the manual page referenced.

    $subsection
        The subsection of the manual page referenced.

Any other text in the template is preserved "as is".

Caution: The man2html utility evaluates the template string as a perl string expression. Therefore, one might need to surround the variable names with '{}' (e.g., ${title}) so that man2html properly recognizes the variable.

Note: If a CGI program calling man2html is actually a shell script or a perl program, make sure to properly escape the '$' character in the URL template to avoid variable interpolation by the CGI program.

Normally, the URL calls a CGI program (hence the option name), but the URL can easily link to statically converted documents.

NOTES
Different systems format manpages differently. Here is a list of recommended command-line options for certain systems:

    Convex:	<defaults should be okay>
    HP:	-leftm 1 -topm 8
    Sun:	-sun (and -solaris when using -k)

Some line spacing is lost in the formatted nroff since the spacing would occur in the middle of a page break. This can cause text to be merged that should not be merged when man2html depaginates the text. To avoid this problem, man2html keeps track of the margin indent right before and after a page break. If the margin width of the line after the page break is less than the line before the page break, then man2html inserts a blank line in the HTML output.

A manpage cross-reference is detected by the following pseudo expression: [A-z.-+_]+([0-9][A-z]?)

The man2html utility only recognizes lines with " - " (the normal separator between manpage references and summary text) while in keyword search mode.

The man2html utility can be hooked in a CGI script/program to convert manpages on the fly. This is the reason for the -cgiurl option.

BUGS
Text that is flush to the left margin, but is not actually a section head, can be mistaken for a section head. This mistake is more likely when the -sun option is in affect.

The order that section head mapping is searched is not defined. Therefore, if two or more <section head text> can match a give manpage section, there is no way to determine which map tag is chosen.

If -seealso is specified, all xrefs are detected after the SEE ALSO heading. In other words, sections after SEE ALSO may contain hyperlinked xrefs.

EXAMPLES

  Using CGI
The following template string is specified to call a CGI program to retrieve the appropriate manpage linked to:

/cgi-bin/man.cgi?section=${section}${subsection}&topic=${title}

If the ls(1) manpage is referenced in the SEE ALSO section, the above template will translate to the following URL:

/cgi-bin/man.cgi?section=1&topic=ls

The actual HTML markup will look like the following:

<A HREF="/cgi-bin/man.cgi?section=1&topic=ls">ls(1)</A>

  Preconverted Manpages
The following template string is specified to retrieve pre-converted manpages:

http://foo.org/man$section/$title.$section$subsection.html

If the mount(1M) manpage is referenced, the above template will translate to the following URL:

http://foo.org/man1/mount.1M.html

The actual HTML markup will look like the following:

<A HREF="http://foo.org/man1/mount.1M.html">mount(1M)</A>

  -cgiurlexp
The option -cgiurlexp is a more general form of the -cgiurl option. -cgiurlexp allows one to specify a general Perl expression. For example:

$title=~/^db_/i?"$title.html":"/cgi-bin/man?$title+$section"

A -cgiurl string can be expressed as follows with -cgiurlexp:

return "string"

  Keyword Search
The man2html utility has the ability to process keyword search output generated by the man -k or apropos commands, through the use of the -k option. The man2html utility will generate an HTML document of the keyword search input having the following format:
    All manpage references are listed by section. Within each section listing, the manpage references are sorted alphabetically (case-sensitive) in a <DL> tag. The manpage references are listed in the <DT> section, and the summary text is listed in the <DD> section. Each manpage reference listed is a hyperlink to the actual manpage as specified by the -cgiurl option.

This ability to process keyword searches gives nice added functionality to a WWW forms interface to man(1). Even if you have statically converted manpages to HTML via another man->HTML program, you can use man2html and "man -k" to provide keyword search capabilities easily for your HTML manpages.

  Processing Keyword Search Results
Unfortunately, there is no standard controlling the format of keyword search results. The man2html utility tries it best to handle all the variations. However, the keyword search results generated by the Solaris operating system are different enough from other systems that a special command-line option (-solaris) must be specified to handle its output.

  Solaris-type keyword search
strcpy        strcpy (9f)  - copy a string from one location to another.
strcpy        string (3c)  - string operations
strncpy       strcpy (9f)  - copy a string from one location to another.
strncpy       string (3c)  - string operations

If keyword search results on your systems appear in the following format:

    <topic> <actual_manpage> (#) - Description

then you need to specify the -solaris option in addition to the -k option.

AUTHORS
Earl Hood
Thomas E. Dickey

Troff version of this document initially created for version 2.1.0 by C. Jeffery Small (jeff@cjsa.com) by copying, reformatting, rearranging and partially rewriting the contents of the ascii text file doc/man2html.txt.

SEE ALSO
man(1), nroff(1), perl(1)

https://invisible-island.net/scripts/man2html.html