SU(C)                    XENIX System V                     SU(C)



     Name
          su - Makes the user a super-user or another user.

     Syntax
          su [ - ] [ name [ arg ... ] ]

     Description
          su allows you to become another user without logging off.
          The default user name is root (i.e., super-user).

          To use su, the appropriate password must be supplied (unless
          you are already a super-user).  If the password is correct,
          su will execute a new shell with the real and effective user
          ID set to that of the specified user.  The new shell will be
          the optional program named in the shell field of the
          specified user's password file (/bin/sh if none is specified
          (see sh(C)).  To restore normal user ID privileges, press
          EOF (Ctrl-D) to the new shell.

          Any additional arguments given on the command line are
          passed to the program invoked as the shell.  When using
          programs like sh(C), an arg of the form -c string executes
          string via the shell and an arg of -r gives the user a
          restricted shell.

          The following statements are true only if the optional
          program named in the shell field of the specified user's
          password file entry is like sh(C).  If the first argument to
          su is a -, the environment is changed to what would be
          expected if the user actually logged in as the specified
          user.  This is done by invoking the program used as the
          shell with an arg0 value whose first character is -, thus
          causing first the system's profile (/etc/profile) and then
          the specified user's profile (.profile in the new HOME
          directory) to be executed.  Otherwise, the environment is
          passed along with the possible exception of $PATH, which is
          set to /bin:/etc:/usr/bin for root.  Note that if the
          optional program used as the shell is /bin/sh, the user's
          .profile can check arg0 for -sh or -su to determine if it
          was invoked by login(M) or su(C), respectively.  If the
          user's program is other than /bin/sh, then .profile is
          invoked with an arg0 of -program by both login(M) and su(C).

          If you want to log all attempts by users to become root,
          create the file /etc/default/su.  In this file, plase a
          string similar to: SULOG=/usr/adm/sulog This causes all
          attempts by any user to switch user id's to be recorded in
          the file /usr/adm/sulog.  This can be any arbitrary
          filename.  The su logfile records the original user, the UID
          of the su attempt, and the time of the attempt.  If the
          attempt is successful, a plus sign (+) is placed on the line
          describing the attempt.  A minus sign (-) indicates an



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     SU(C)                    XENIX System V                     SU(C)



          unsuccessful attempt.

     Examples
          To become user bin while retaining your previously exported
          environment, enter:

               su bin

          To become user bin but change the environment to what would
          be expected if bin had originally logged in, enter:

               su - bin

          To execute command with the temporary environment and
          permissions of user bin, enter:

               su - bin -c ``command args''

     Files
          /etc/passwd         The system password file
          /etc/default/su          Optional file giving location of
          sulog.
          /etc/profile        The system profile
          $HOME/.profile The user profile

     See Also
          env(C), environ(M), login(M), passwd(M), profile(M), sh(C)




























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