HELP(1)                    OpenBSD Reference Manual                    HELP(1)

NAME
     help - help for new users and administrators

DESCRIPTION
     This document is meant to familiarize new users and system administrators
     with OpenBSD and, if necessary, UNIX in general.

     Firstly, a wealth of information is contained within the system manual
     pages.  In UNIX, the man(1) command is used to view them.  Type man man
     for instructions on how to use it properly.  Pay especially close atten-
     tion to the -k option.

     Other OpenBSD references include the FAQ (Frequently Asked Questions) lo-
     cated at http://www.openbsd.org/faq, which is mostly intended for admin-
     istrators and assumes the reader possesses a working knowledge of UNIX.
     There are also mailing lists in place where questions are fielded by
     OpenBSD developers and other users; see http://www.openbsd.org/mail.html.

     System administrators should have already read the afterboot(8) man page
     which explains a variety of tasks that are typically performed after the
     first system boot.  When configuring any aspect of the system, first con-
     sider any possible security implications your changes may have.

   The Unix shell
     After logging in, some system messages are typically displayed, and then
     the user is able to enter commands to be processed by the shell program.
     The shell is a command-line interpreter that reads user input (normally
     from a terminal) and executes commands.  There are many different shells
     available; OpenBSD ships with csh(1), ksh(1), and sh(1).  Each user's
     shell is indicated by the last field of their corresponding entry in the
     system password file (/etc/passwd).

   Basic Unix commands

     man       Interface to the system manual pages.  For any of the commands
               listed below, type man <command> for detailed information on
               what it does and how to use it.

     pwd       Print working directory.  Files are organized in a hierarchy
               (see hier(7)) called a tree.  This command will indicate in
               which directory you are currently located.

     cd        Change working directory.  Use this command to navigate
               throughout the file hierarchy.  For example, type cd / to
               change the working directory to the root.

     ls        List directory contents.  Type ls -l for a detailed listing.

     cat       Although it has many more uses, cat filename will print the
               contents of a plain-text file to the screen.

     mkdir     Make a directory.  For example, mkdir foobar.

     rmdir     Remove a directory.

     rm        Remove files.  Files are generally only removable by their own-
               ers.  See the chmod(1) command for information on file permis-
               sions.

     chmod     Change file modes, including permissions.  It is not immediate-
               ly obvious how to use this command; please read its manual page
               carefully, as proper file permissions, especially on system
               files, are vital in maintaining security and integrity.

     cp        Copy files.

     mv        Move and rename files.

     ps        List active processes.  Most UNIX-based operating systems, in-
               cluding OpenBSD, are multitasking, meaning many programs share
               system resources at the same time.  A common usage is ps -auxw,
               which will display information about all active processes.

     kill      Kill processes.  Used mostly for terminating run-away/unrespon-
               sive programs, but also used to signal programs for requesting
               certain operations (e.g., re-read their configuration).

     date      Print the current system date and time.

     mail      Access mailbox.

     exit      Log out of the system.

     When a command is entered, it is first checked to see if it is built-in
     to the shell.  If not, the shell looks for the command in any directories
     contained within the PATH environment variable (see environ(7)).  If the
     command is not found, an error message is printed.  Otherwise, the shell
     runs the command, passing it any arguments specified on the command line.

     Shell built-in commands do not have their own manual page, so it's neces-
     sary to read the manual page for the user's shell.  Tools such as
     which(1) and ``whence'', a ksh(1) built-in command, can be used to see
     what commands are being executed.

SEE ALSO
     csh(1), ksh(1), man(1), whatis(1), whereis(1), which(1), afterboot(8)

HISTORY
     This manual page was written by Aaron Campbell <aaron@openbsd.org> and
     first appeared in OpenBSD 2.6.

OpenBSD 4.7                    January 11, 2008                              2
