--- name: "manweb" section: "1" platform: "linux" package: "netpbm" version: "10.86.51-2" release: "Arch Linux 2026-11-01" platforms: ["linux"] url: "https://new.carta.tech/manweb" --- # manweb(1) .SH NAME manweb - browse netpbm (and other) documentation ## SYNOPSIS **manweb** **-help** **manweb** \[**-config=***configfile\]* *\[topic \[ subtopic ... \] \]* ## EXAMPLES ``` manweb ``` *This gets a master index of documentation.* ``` manweb netpbm ``` *This gets the main documentation page for the Netpbm package, with hyperlinks* *to the rest of the documentation.* ``` manweb netpbm pngtopam ``` *This goes directly to the documentation page for the Pngtopam program in* *the Netpbm package.* ``` manweb pngtopam ``` *This also goes directly to the documentation page for the Pngtopam program in* *the Netpbm package, if that's what would run in response to a* **pngtopam** *shell command (your* **PATH** *environment variable is involved).* ``` manweb 3 fopen ``` *This gets the traditional man page for the fopen() subroutine using* **man***.* ``` manweb cp ``` *This gets the GNU Info manual for the* **cp** *program, using* **info***.* ## DESCRIPTION **manweb** *displays reference documentation via quick shell* *commands. It is a replacement for the well-known* **man***.* ## Differences Between Man and Manweb **manweb***'s advantages over* **man** *are:* - • *You can access documentation that is on the worldwide web instead of*\ *having locally installed copies. This saves installation work and gets*\ *you more current documentation.* - • *Documentation can be in HTML, which is more widely known, more widely*\ *useful, and more expressive than the nroff/troff format used by*\ **man***.* - • **manweb** *puts your topics in a tree for multilevel documentation.*\ **man** *is intended for a single level of documentation. For*\ *example, you can have a man page for each shell command, but not for*\ *the subcommands of a shell command. And you cannot properly have*\ *man pages for the members of multiple subroutine libraries.* - • *Documentation can be hyperlinked.* *Web servers need not be involved -- the documentation can be in local* *files. Graphics need not be involved -- the* **lynx** *browser works fine* *in the same kind of terminals in which* **man** *works.* **manweb** *finds the documentation you specify and calls a web* *browser of your choice to display it. The documentation* **manweb** *finds can be either an HTML file on your system, in which case,* **manweb** *gives a* **file:** *URL to your browser, or an explicit* *URL. That explicit URL might be an* **http:** *URL referring to an* *HTML file on a web server somewhere, or anything else your browser* *understands.* *If* **manweb** *finds neither an HTML file nor a URL, but your parameters* *look like they could mean something to* **man***,* **manweb** *calls* **man***. Therefore, you can use a single command to access the vast* *body of traditional man pages, plus any newer* **manweb** *documentation.* *You can make "man" a shell alias of "manweb".* **manweb** *finds Info documentation as well. It looks for the* *topic you specify as an Info topic after looking for HTML and URL* *documentation and before running* **man***. If* **manweb** *finds a* *corresponding Info topic, it runs the program* **info** *on it. Info* *is the documentation system that the GNU project invented to, among* *other things, replace traditional Unix man pages. However, HTML and the* *Worldwide Web were invented shortly afterward, so Info fizzled. But there* *is still a lot of GNU software that is documented as Info topics.* ### How Manweb Finds Documentation **manweb** *passes a URL to a web browser. This section tells* *how your* **manweb** *invocation parameters turn into that URL.* **manweb***'s search starts in the "web directory" directory.* *That's either the value of the* **webdir** *keyword in your* **manweb** *configuration file, or the default* **/usr/man/web***.* *Your invocation parameters form a "topic chain." Going from left to right,* *the first parameter is the main topic, the 2nd is a subtopic of the main* *topic, and so on.* *Let's look at the simple case where you specify exactly one parameter --* *a main topic. We'll call it maintopic and look at 4 ways* **manweb** *might find it:* - • *If* **manweb** *finds a file named maintopic***.html**\ *in the web directory, the URL* **manweb** *passes to the*\ *browser is just a* **file:** *URL that specifies that .html*\ *file.* - • *If there's no .html file, but there is a file named*\ *maintopic***.url***, the contents of the first line of*\ *that .url file is what* **manweb** *passes to the browser. It*\ *doesn't interpret the contents at all. If it's garbage, the*\ *browser chokes on it.* - • *If there's neither a .html nor a .url file, but there is a*\ *directory named maintopic,* **manweb** *looks in the*\ *directory for a file named index.html. If there is one,*\ **manweb** *passes a* **file:** *URL specifying that*\ *index.html file to the browser. If there's no*\ *index.html,* **manweb** *uses a* **file:** *URL that*\ *specifies the directory itself.* - • *If* **manweb** *doesn't find documentation in any of the*\ *above ways, it searches your executable search path (as defined*\ *by your* **PATH** *environment variable) for a program named*\ *maintopic. If it finds one, it looks in the directory*\ *that contains the program for a file named* **doc.url***. If*\ *it finds one, it appends maintopic***.html** *to the*\ *first line of the file and passes that to the browser. Unless* \ *the first line does not end with a slash -- in that* \ *case,* **manweb** *passes the first line of the file unmodified*\ *to the browser.* *It gets a little more interesting when you have subtopics. Looking* *at each of the 4 cases above:* - • *Where maintopic***.html** *exists, subtopics are invalid.*\ *You get a warning message and the subtopics are ignored.* - • *Where there's no .html file but maintopic***.url** *exists,*\ **manweb** *appends the subtopic chain to the URL it gets from the*\ *.url file as in the following example: .url file contains*\ **http://acme.com/productxyz/** *and subtopics are*\ **create** *and*\ **database***. The URL* **manweb** *passes to the browser is*\ **http://acme.com/productxyz/create/database.html***.* **manweb** *doesn't check that this kind of appendage makes*\ *any sense for the URL in question, except that if the URL in the*\ *.url file doesn't end with a slash (***/***),* **manweb**\ *issues a warning and doesn't append anything (ignores the subtopics).* - • *Where there's neither a .html file nor a .url file, but there's a*\ *maintopic directory,* **manweb** *recurses into that*\ *directory and begins a whole new search using the first subtopic*\ *as the main topic and the rest of the subtopics as subtopics of that.* - • *When there are subtopics, the* **PATH** *thing doesn't make sense,*\ *so* **manweb** *doesn't do it.* *If you give subtopics, the* **PATH** *thing described above for one* *topic doesn't apply.* *If you give no parameters at all,* **manweb** *generates a URL for the* *web directory itself as described above for subdirectories.* *The above is simplified by the assumption of a single web* *directory. In reality, the* **webdir** *keyword in the configuration* *file can specify a chain of web directories.* **manweb** *searches* *each one in turn, doing all the kinds of searches in each web directory* *before moving on to the next one.* ### The Configuration File *The default location of the* **manweb** *configuration file is* **/etc/manweb.conf***. But you can override this with the environment* *variable* **MANWEB\_CONF\_FILE***, and override that with the* **-config** *invocation option.* *Lines starting with "#" are comments and are ignored, as are blank lines.* *All other lines have the format keyword=value. The* *keywords defined are:* - *webdir* *A colon-delimited sequence of directories to search for*\ *documentation as described above. If you*\ *don't specify this, the default is* **/usr/man/web** *alone.* - *browser* *The file specification* **manweb** *of the web browser* **manweb**\ *is to invoke*\ *to display documentation (except when it uses* **man** *to display*\ *a conventional man page).*\ *If the file specification does not include a slash,* **manweb**\ *searches for the file in the PATH search path.* *If you don't specify this, the default is the value of the*\ **BROWSER** *environment variable, and if that is not set,*\ **lynx***.* *Example:* ``` # Configuration file for Manweb webdir=/usr/share/manweb browser=netscape ``` ### How To Make HTML Documentation *Pages displayed by* **manweb** *don't have to have any particular*\ *format. You can write anything you want in HTML, using any web page*\ *generation tools or just by typing HTML in a text editor.* *Readers might appreciate something roughly in the format of classic Unix*\ *man pages (Name, Synopsis, etc.).* *You can convert legacy nroff/troff man pages to passable HTML with the*\ *program* **mandoc***. You don't have to do this just to access the*\ *information with* **manweb***, because* **manweb** *falls back to*\ *invoking* **man** *if it doesn't find HTML pages, but if you are*\ *maintaining documentation, you might use this as a starting point for*\ *maintaining it in HTML in the future.* *Example:* ``` $ mandoc -T html foo.1 >foo.html ``` *With a large number of pages, you could use* **find** *to do them all at*\ *once and* **parallel** *to do them more quickly.* *If you're converting a large collection of man pages, you'll have*\ *to deal with linked header files and linked manuals (where the troff*\ *man page refers to other pages) with something like this:* ``` $ mandoc -T html -O includes='./%N.html'; -O man='%N.%S.html' ... ``` *This creates similar HTML links to HTML file names, and you then make symbolic* *links for those names.* ## DOCUMENT SOURCE *This manual page was generated by the Netpbm tool 'makeman' from HTML* *source. The master documentation is at* - **http://netpbm.sourceforge.net/doc/manweb.html**