man page

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man pages—abbreviation for "manual pages"—are the form of documentation that is available on almost all UNIX-like operating systems, including Arch Linux. The command used to display them is man.

In spite of their scope, man pages are designed to be self-contained documents, consequentially limiting themselves to referring to other man pages when discussing related subjects. This is in sharp contrast with the hyperlink-aware Info documents, GNU's attempt at replacing the traditional man page format.

Installation

man-db implements man on Arch Linux, and less is the default pager used with man. mandoc can also be used.

man-pages provides the Linux man pages.

Some localized man pages are also available:

You can use some applications to view man pages:

  • GNOME Help — Help viewer for GNOME. It can show man pages via yelp man:<name> or the undocumented Ctrl+L keybinding from an existing window.
https://wiki.gnome.org/Apps/Yelp || yelp
  • KHelpCenter — Application to show KDE Applications' documentation. Man pages are in UNIX manual pages or by running khelpcenter man:<name>.
https://userbase.kde.org/KHelpCenter || khelpcenter
  • Konqueror — KDE file manager and web browser. It can show man pages via man:<name>.
https://konqueror.org/ || konqueror
  • xman — Provides a categorized look at man pages.
https://xorg.freedesktop.org/ || xorg-xman

Accessing man pages

To read a man page, simply enter: 

$ man page_name

Manuals are sorted into several sections. For a full listing see the section entitled "Sections of the manual pages" in man-pages(7).

Man pages are usually referred to by their name, followed by their section number in parentheses. Often there are multiple man pages of the same name, such as man(1) and man(7). In this case, give man the section number followed by the name of the man page, for example: 

$ man 5 passwd

to read the man page on /etc/passwd, rather than the passwd utility.

Or equivalently, the man page followed by the section number, separated by a period: 

$ man passwd.5

Searching manuals

Man pages can be searched when the exact name of a page is not known using any of the following equivalent commands: 

$ man -k expression
$ man --apropos expression
$ apropos expression

expression is interpreted as a regular expression by default.

To search for keywords in whole page texts, use the -K option instead.

Note: The search feature is provided by a dedicated cache. By default, maintenance of that cache is handled by man-db.service which gets periodically triggered by man-db.timer. If you are getting a "nothing appropriate" message for every search, try manually regenerating the cache by running mandb as root.

One-line descriptions of man pages can be displayed using the whatis command. For example, for a brief description of the man page sections about ls, type: 

$ whatis ls
ls (1p)              - list directory contents
ls (1)               - list directory contents

Page width

The man page width is controlled by the MANWIDTH environment variable.

If the number of columns in the terminal is too small (e.g. the window width is narrow), the line breaks will be wrong. This can be very disturbing for reading. You can fix this by setting the MANWIDTH on man invocation. With Bash, that would be: 

~/.bashrc
man() {
    local width=$(tput cols)
    [ $width -gt $MANWIDTH ] && width=$MANWIDTH
    env MANWIDTH=$width \
    man "$@"
}

Reading local man pages

Instead of the standard interface, using browsers such as lynx and Firefox to view man pages allows users to reap info pages' main benefit of hyperlinked text. Alternatives include the following:

Conversion to HTML

mandoc

Install the mandoc package. To convert a page, for example free(1): 

$ mandoc -Thtml -Ostyle=style.css /usr/share/man/man1/free.1.gz > free.html

Now open the file called free.html in your favourite browser.

man2html

First, install man2html from the official repositories.

Now, convert a man page: 

$ man free | man2html -compress -cgiurl man$section/$title.$section$subsection.html > ~/man/free.html

Another use for man2html is exporting to raw, printer-friendly text: 

$ man free | man2html -bare > ~/free.txt

man -H

The man-db implementation also has the ability to do this on its own: 

$ man -H free

This will read your BROWSER environment variable to determine the browser. You can override this by passing the binary to the -H option.

roffit

First install roffitAUR from AUR.

To convert a man page: 

$ gunzip -c /usr/share/man/man1/free.1.gz | roffit > free.html

Conversion to PDF

man pages have always been printable: they are written in troff(1), which is fundamentally a typesetting language. Therefore, you can easily convert man pages to any of the formats supported as output devices by groff, which is used by man-db. For a list of output devices, see the -T option in groff(1) (or mandoc(1) if you use the mandoc package).

This will produce a PDF file: 

$ man -Tpdf manpage > filename

Caveats: Fonts are generally limited to Times at hardcoded sizes. Some man pages were specifically designed for terminal viewing, and will not look right in PS or PDF form.

Online man pages

There are several online databases of man pages, including:

There is also a comparison table.

Warning: Some distributions provide patched or outdated man pages that differ from those provided by Arch. Exercise caution when using online man pages.

Noteworthy man pages

Here follows a non-exhaustive list of noteworthy pages that might help you understand a lot of things more in-depth. Some of them might serve as a good reference (like the ASCII table).

More generally, have a look at category 7 (miscellaneous) pages: 

$ man -s 7 -k ".*"

Arch Linux specific pages:

See also