Unix BasicsThe Online ManualThe most comprehensive documentation on FreeBSD is in the form of
man pages. Nearly every program on the system
comes with a short reference manual explaining the basic operation and
various arguments. These manuals can be view with the
man command. Use of the man
command is simple:&prompt.user; man commandcommand is the name of the command you
wish to learn about. For example, to learn more about
ls command type:&prompt.user; man lsThe online manual is divided up into numbered sections:User commandsSystem calls and error numbersFunctions in the C librariesDevice driversFile formatsGames and other diversionsMiscellaneous informationSystem maintenance and operation commandsKernel developersIn some cases, the same topic may appear in more than one section of
the on-line manual. For example, there is a chmod
user command and a chmod() system call. In this
case, you can tell the man command which one you want
by specifying the section:&prompt.user; man 1 chmodThis will display the manual page for the user command
chmod. References to a particular section of the
on-line manual are traditionally placed in parenthesis in written
documentation, so &man.chmod.1; refers to the
chmod user command and &man.chmod.2; refers to the
system call.This is fine if you know the name of the command and simply wish to
know how to use it, but what if you cannot recall the command name? You
can use man to search for keywords in the command
descriptions by using the
switch:&prompt.user; man -k mailWith this command you will be presented with a list of commands that
have the keyword “mail” in their descriptions. This is
actually functionally equivalent to using the apropos
command.So, you are looking at all those fancy commands in
/usr/bin but do not even have the faintest idea
what most of them actually do? Simply do a
&prompt.user; cd /usr/bin; man -f *
or
&prompt.user; cd /usr/bin; whatis *
which does the same thing.GNU Info FilesFreeBSD includes many applications and utilities produced by the
Free Software Foundation (FSF). In addition to man pages, these
programs come with more extensive hypertext documents called
“info” files which can be viewed with the
info command or, if you installed
emacs, the info mode of
emacs.To use the &man.info.1; command, simply type:&prompt.user; infoFor a brief introduction, type h. For a
quick command reference, type ?.