man.cgi — CGI
program to search and display manual pages
CGI program searches for manual pages on a
WWW server and displays them to HTTP clients, providing functionality
equivalent to the man(1)
utilities. It can use multiple
manual trees in parallel.
At the top of each generated HTML page,
man.cgi displays a search form containing these
- An input box for search queries, expecting either a name of a manual page
or an expression using the syntax described in the
apropos(1) manual; filling this in is
required for each search.
The expression is broken into words at whitespace. Whitespace
characters and backslashes can be escaped by prepending a backslash. The
effect of prepending a backslash to another character is undefined; in
the current implementation, it has no effect.
- A man(1) submit button. The string in the
input box is interpreted as the name of a manual page.
- An apropos(1) submit button. The
string in the input box is interpreted as a search
- A dropdown menu to optionally select a manual section. If one is provided,
it has the same effect as the man(1) and
option. Otherwise, pages from all sections are shown.
- A dropdown menu to optionally select an architecture. If one is provided,
it has the same effect as the man(1) and
option. By default, pages for all architectures are shown.
- A dropdown menu to select a manual tree. If the configuration file
/var/www/man/manpath.conf contains only one
manpath, the dropdown menu is not shown. By default, the first manpath
given in the file is used.
man.cgi program generates five kinds
of output pages:
- The index page.
- This is returned when calling
PATH_INFO and without a
QUERY_STRING. It serves as a starting point for
using the program and shows the search form only.
- A list page.
- Lists are returned when searches match more than one manual page. The
first column shows the names and section numbers of manuals as clickable
links. The second column shows the one-line descriptions of the manuals.
For man(1) style searches, the content of
the first manual page follows the list.
- A manual page.
- This output format is used when a search matches exactly one manual page,
or when a link on a list page or an
Xr link on
another manual page is followed.
- A no-result page.
- This is shown when a search request returns no results - either because it
violates the query syntax, or because the search does not match any manual
- An error page.
- This cannot happen by merely clicking the “Search” button,
but only by manually entering an invalid URI. It does not show the search
form, but only an error message and a link back to the index page.
For each manual tree, create one first-level subdirectory below
/var/www/man. The name of one of these directories
is called a “manpath” in the context of
man.cgi. Create a single ASCII text file
/var/www/man/manpath.conf containing the names of
these directories, one per line. The directory given first is used as the
Inside each of these directories, use the same directory and file
structure as found below /usr/share/man, that is,
second-level subdirectories /var/www/man/*/man1,
/var/www/man/*/man2 etc. containing source
man(7) manuals with file name extensions
matching the section numbers, second-level subdirectories
/var/www/man/*/cat2 etc. containing preformatted
manuals with the file name extension ‘0’, and optional
third-level subdirectories for architectures. Use
makewhatis(8) to create a
mandoc.db(5) database inside each
Configure your web server to execute CGI programs located in
/cgi-bin. When using OpenBSD
slowcgi(8) proxy daemon is needed to
translate FastCGI requests to plain old CGI.
man.cgi, first copy
cgi.h.example to cgi.h and
edit it according to your needs. It contains the following compile-time
- Only useful for running on www.openbsd.org to deal with old URIs
containing "manpath=OpenBSD " where the blank character has to
be translated to a hyphen. When compiling for other sites, this definition
can be deleted.
- An optional file system path to the directory containing the file
mandoc.css, to be specified relative to the
server's document root, and to be specified without a trailing slash. When
empty, the CSS file is assumed to be in the document root. Otherwise, a
leading slash is needed. This is used in generated HTML code.
- An ASCII string to be used for the HTML <TITLE> element.
- A file system path to the
man.cgi data directory
relative to the web server chroot(2)
directory, to be specified with a leading slash and without a trailing
slash. It needs to have at least one component; the root directory cannot
be used for this purpose. The files manpath.conf,
footer.html are looked up in this directory. It is
also prepended to the manpath when opening
mandoc.db(5) and manual page
- The initial component of URIs, to be specified without leading and
trailing slashes. It can be empty.
After editing cgi.h, run
and copy the resulting binary to the proper location, for example
using the command:
In addition to that, make sure the default manpath contains the
files man1/apropos.1 and
man8/man.cgi.8, or the documentation links at the
bottom of the index page will not work.
man.cgi uniform resource identifiers are
not needed for interactive use, but can be useful for deep linking. They
- The host name.
SCRIPT_NAME, preceded by a slash unless
- To show a single page, a slash, the manpath, another slash, and the name
of the requested file, for example
/OpenBSD-current/man1/mandoc.1. This can be
abbreviated according to the following syntax:
- For searches, a query string starting with a question mark and consisting
of key=value pairs, separated
by ampersands, for example
Supported keys are
arch, corresponding to
-S, respectively, and
apropos, which is a boolean parameter to select or
deselect the apropos(1) query mode.
For backward compatibility with the traditional
supported as an alias for
For security reasons, in particular to prevent cross site
scripting attacks, some strings used by
only contain the following characters:
- lower case and upper case ASCII letters
- the ten decimal digits
- the dash (‘-’)
- the dot (‘.’)
- the slash (‘/’)
- the underscore (‘_’)
In particular, this applies to all manpaths and architecture
The web server may pass the following CGI variables to
- The initial part of the URI passed from the client to the server, starting
after the server's host name and ending before
PATH_INFO. This is ignored by
man.cgi. When constructing URIs for links and
constant is used instead.
- The final part of the URI path passed from the client to the server,
starting after the
SCRIPT_NAME and ending before
QUERY_STRING. It is used by the
show page to acquire the manpath and filename it
- The HTTP query string passed from the client to the server. It is the
final part of the URI, after the question mark. It is used by the
search page to acquire the named parameters it
- Default web server chroot(2) directory.
All the following paths are specified relative to this directory.
- The usual file system path to the
inside the web server chroot(2)
directory. A different name can be chosen, but in any case, it needs to be
configured in httpd.conf(5).
- The file system path to the server document root directory relative to the
server chroot(2) directory. This is
part of the web server configuration and not specific to
- A style sheet for mandoc(1) HTML
styling, referenced from each generated HTML page.
man.cgi data directory containing all the
manual trees. Can be overridden by
- The list of available manpaths, one per line. If any of the lines in this
file contains a slash (‘/’) or any character not contained
in the Restricted character
man.cgi reports an internal server error
and exits without doing anything.
- An optional file containing static HTML code to be inserted right after
opening the <BODY> element.
- An optional file containing static HTML code to be inserted right before
closing the <BODY> element.
- An example mdoc(7) source file located
below the “OpenBSD-current” manpath.
man.cgi CGI program is call-compatible
with queries from the traditional man.cgi script by
Wolfram Schneider. However, the output looks quite different.
A version of
man.cgi based on
mandoc(1) first appeared in mdocml-1.12.1
(March 2012). The current mandoc.db(5)
database format first appeared in OpenBSD 6.1.
man.cgi program was written by
is maintained by Ingo Schwarze
who also designed and implemented the database format.