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 commandsIn 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 chmod1 refers to the
chmod
user command and chmod2 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 info1 command, simply type:&prompt.user; infoFor a brief introduction, type h. For a quick
command reference, type ?.