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Most UBOs have manual pages.

MAN(1)                     OpenBSD Reference Manual                     MAN(1)
    man - display the on-line manual pages
    man [-achw] [-C file] [-M path] [-m path] [-S subsection] [-s section]
        [section] name [...]
    man -f command
    man -k keyword

The types of manpages have sections which they are grouped in. Here is the manual page layout of BSD:

Section 1
General commands (tools and utilities)
Section 2
System calls and error numbers
Section 3
Library functions, especially for C and Tk
Section 4
Special files and hardware support
Section 5
File formats, especially configuration files
Section 6
Section 7
Miscellaneous information pages
Section 8
System maintenance and operation commands
Section 9
Kernel internals

When someone tells you to run "man 6 tetris", that means that you should read the tetris manpage found in section 6 of the manpages. Sometimes the same manpage name exists, but in different sections. One example is the fstat manpage it exists in sections 1 and 2. The lower number sections take precedence over higher numbered sections. Thus, to see the manpage for fstat in section 2 you would type:

$ man 2 fstat

Similarely functions, syscalls or commands are sometimes mentioned with the section of manpages in brackets behind them like so: fstat(2), you'll see this mentioned a lot in this wiki.

Simple example to type at your shell prompt of most UBOs:

$ man 1 intro

This brings up the man page for intro(1). You can use your spacebar to go down a page, and "q" for quit.

Installing manpages

On Debian based GNU/Linux:

$ sudo apt-get install manpages

Creating windex

If you're looking for a man page and get the following:

# man -k snoop
/usr/share/man/windex: No such file or directory

It means you have yet to create your Index:

# /usr/bin/catman -w 

Searching for Manual Pages

It is possible to do a keyword search in the manpage system.

$ man -k filesystem
OpenBSD::Vstat (3p) - virtual filesystem for pkg_add(1) simulations
dump (8) - filesystem backup
fstab (5) - static information about the filesystems

Another command synonymous to man -k is apropos:

$ apropos archiver
tar (1) - tape archiver

Do notice that the section of the manpage is displayed in the keyword search, this is to ease viewing the particular manpage.

$MANPATH is used, unless something else is explicitly specified.

Location of Manual Pages

In BSD the default manual pages are located in /usr/share/man. This can be changed with the MANPATH environment variable:

$ export MANPATH=/usr/local/man
$ man ls
man: no entry for ls in the manual. 
$ unset MANPATH
$ man ls
LS(1)                      OpenBSD Reference Manual                      LS(1)

Another manpage section can be added on to the current MANPATH:

$ export MANPATH=/usr/share/man:/usr/local/man

Searching in a man page

Often you will want to search a man page you are viewing for a particular keyword. You can preceed this search word with a "/". If I wanted to see what mediaopt(ions) my sis NIC has I could do


while reading the sis(4) manpage I have on my system. If the first result is not what I want, I don't have to type the full search word after the first time, I can simply use


which is to "find another instance". This btw can also be achieved by typing "n" (lowercase) to search forward and "N" (uppercase) to search backwards, at least on FreeBSD.