tion is specified.

       SUDO_COMMAND     Set to the command run by sudo, including any args. The
                        args  are truncated at 4096 characters to prevent a po‐
                        tential execution error.

       SUDO_EDITOR      Default editor to use in -e (sudoedit) mode.

       SUDO_GID         Set to the group‐ID of the user who invoked sudo.

       SUDO_PROMPT      Used as the default password prompt unless the  -p  op‐
                        tion was specified.

       SUDO_PS1         If  set,  PS1  will be set to its value for the program
                        being run.

       SUDO_UID         Set to the user‐ID of the user who invoked sudo.

       SUDO_USER        Set to the login name of the user who invoked sudo.

       USER             Set to the same value as LOGNAME, described above.

       VISUAL           Default  editor  to  use  in  -e  (sudoedit)  mode   if
                        SUDO_EDITOR is not set.

FILES
       /etc/sudo.conf            sudo front‐end configuration

EXAMPLES
       The following examples assume a properly configured security policy.

       To get a file listing of an unreadable directory:

           $ sudo ls /usr/local/protected

       To  list the home directory of user yaz on a machine where the file sys‐
       tem holding ~yaz is not exported as root:

           $ sudo ‐u yaz ls ~yaz

       To edit the index.html file as user www:

           $ sudoedit ‐u www ~www/htdocs/index.html

       To view system logs only accessible to root and users in the adm group:

           $ sudo ‐g adm more /var/log/syslog

       To run an editor as jim with a different primary group:

           $ sudoedit ‐u jim ‐g audio ~jim/sound.txt

       To shut down a machine:

           $ sudo shutdown ‐r +15 "quick reboot"

       To make a usage listing of the directories in the /home partition.   The
       commands are run in a sub‐shell to allow the ‘cd’ command and file redi‐
       rection to work.

           $ sudo sh ‐c "cd /home ; du ‐s * | sort ‐rn > USAGE"

DIAGNOSTICS
       Error messages produced by sudo include:

       editing files in a writable directory is not permitted
             By  default,  sudoedit  does not permit editing a file when any of
             the parent directories are writable by the  invoking  user.   This
             avoids  a race condition that could allow the user to overwrite an
             arbitrary file.  See the sudoedit_checkdir  option  in  sudoers(5)
             for more information.

       editing symbolic links is not permitted
             By  default,  sudoedit does not follow symbolic links when opening
             files.  See the sudoedit_follow option in sudoers(5) for more  in‐
             formation.

       effective uid is not 0, is sudo installed setuid root?
             sudo  was  not  run with root privileges.  The sudo binary must be
             owned by the root user and have the set‐user‐ID bit set.  Also, it
             must not be located on a file system mounted with the ‘nosuid’ op‐
             tion or on an NFS file system that maps uid 0 to  an  unprivileged
             uid.

       effective  uid  is  not  0,  is  sudo on a file system with the ’nosuid’
             option set or an NFS file system without root privileges?
             sudo was not run with root privileges.  The sudo  binary  has  the
             proper  owner  and  permissions but it still did not run with root
             privileges.  The most common reason for this is that the file sys‐
             tem the sudo binary is located on is mounted with the ‘nosuid’ op‐
             tion or it is an NFS file system that maps uid 0  to  an  unprivi‐
             leged uid.

       fatal error, unable to load plugins
             An error occurred while loading or initializing the plugins speci‐
             fied in sudo.conf(5).

       invalid environment variable name
             One or more