Provided by: login_4.1.1-1ubuntu1_i386 bug

NOME

       su - change user ID or become superuser

SINOSSI

       su [opzioni] [LOGIN]

DESCRIZIONE

       The su command is used to become another user during a login session.
       Invoked without a username, su defaults to becoming the superuser. The
       optional argument - may be used to provide an environment similar to
       what the user would expect had the user logged in directly.

       Dopo il nome utente, è possibile specificare argomenti aggiuntivi da
       passare alla shell di login dell´utente. In particolare, molti
       interpreti di comando adottano la convenzione per cui l´opzione -c
       seguita da un argomento fa sì che quest´ultimo sia considerato un
       comando.Il comando viene eseguito dalla shell specificata in
       /etc/passwd per l´utente di destinazione.

       You can use the -- argument to separate su options from the arguments
       supplied to the shell.

       All´utente viene quindi chiesta la password, se necessario. Una
       password errata viene segnalata da un messaggio d´errore. Viene
       effettuato il log di tutti i tentativi, siano essi riusciti o meno, al
       fine di rilevare ogni abuso del sistema.

       The current environment is passed to the new shell. The value of $PATH
       is reset to /bin:/usr/bin for normal users, or
       /sbin:/bin:/usr/sbin:/usr/bin for the superuser. This may be changed
       with the ENV_PATH and ENV_SUPATH definitions in /etc/login.defs.

       A subsystem login is indicated by the presence of a "*" as the first
       character of the login shell. The given home directory will be used as
       the root of a new file system which the user is actually logged into.

OPZIONI

       Il comando su accetta le seguenti opzioni:

       -c, --command COMMAND
           Specify a command that will be invoked by the shell using its -c.

       -, -l, --login
           Provide an environment similar to what the user would expect had
           the user logged in directly.

           When - is used, it must be specified as the last su option. The
           other forms (-l and --login) do not have this restriction.

       -s, --shell SHELL
           The shell that will be invoked.

           The invoked shell is chosen from (highest priority first):

           ·   The shell specified with --shell.

           ·   If --preserve-environment is used, the shell specified by the
               $SHELL environment variable.

           ·   The shell indicated in the /etc/passwd entry for the target
               user.

           ·    /bin/sh if a shell could not be found by any above method.

               If the target user has a restricted shell (i.e. the shell field
               of this user´s entry in /etc/passwd is not listed in
               /etc/shell), then the --shell option or the $SHELL environment
               variable won´t be taken into account, unless su is called by
               root.

       -m, -p, --preserve-environment
           Preserve the current environment.

           If the target user has a restricted shell, this option has no
           effect (unless su is called by root).

AVVISI/CAVEAT

       Questa versione di su ha molte opzioni di compilazione; solo una parte
       di esse potrebbe essere in uso su un determinato sistema.

CONFIGURATION

       The following configuration variables in /etc/login.defs change the
       behavior of this tool:

       CONSOLE_GROUPS (string)
           List of groups to add to the user´s supplementary group set when
           logging in on the console (as determined by the CONSOLE setting).
           Default is none.

           Use with caution - it is possible for users to gain permanent
           access to these groups, even when not logged in on the console.

       DEFAULT_HOME (boolean)
           Indicate if login is allowed if we can´t cd to the home directory.
           Default in no.

           If set to yes, the user will login in the root (/) directory if it
           is not possible to cd to her home directory.

       ENV_PATH (string)
           If set, it will be used to define the PATH environment variable
           when a regular user login. The value can be preceded by PATH=, or a
           colon separated list of paths (for example /bin:/usr/bin). The
           default value is PATH=/bin:/usr/bin.

       ENV_SUPATH (string)
           If set, it will be used to define the PATH environment variable
           when the superuser login. The value can be preceded by PATH=, or a
           colon separated list of paths (for example
           /sbin:/bin:/usr/sbin:/usr/bin). The default value is
           PATH=/bin:/usr/bin.

       SULOG_FILE (string)
           If defined, all su activity is logged to this file.

       SU_NAME (string)
           If defined, the command name to display when running "su -". For
           example, if this is defined as "su" then a "ps" will display the
           command is "-su". If not defined, then "ps" would display the name
           of the shell actually being run, e.g. something like "-sh".

       SYSLOG_SU_ENAB (boolean)
           Enable "syslog" logging of su activity - in addition to sulog file
           logging.

FILE

       /etc/passwd
           informazioni sugli account utente.

       /etc/shadow
           Informazioni sicure sugli account di utenti.

VEDERE ANCHE

       login(1), login.defs(5), sg(1), sh(1)