su(1M)                UNIX System V(Essential Utilities)                 su(1M)


NAME
      su - become super-user or another user

SYNOPSIS
      su [ - ] [ name [ arg ... ] ]

DESCRIPTION
      su allows one to become another user without logging off.  The default
      user name is root (that is, super-user).

      To use su, the appropriate password must be supplied (unless one is
      already root).  If the password is correct, su will execute a new shell
      with the real and effective user and group IDs and supplementary group
      list 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 entry [see passwd(4)] or /usr/bin/sh if none is specified
      [see sh(1)].  To restore normal user ID privileges, type an EOF character
      (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 such as sh, 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.
      If the first argument to su is a -, the environment will be 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
      /sbin:/usr/sbin:/usr/bin:/etc for root.  Note that if the optional
      program used as the shell is /usr/bin/sh, the user's .profile can check
      arg0 for -sh or -su to determine if it was invoked by login or su,
      respectively.  If the user's program is other than /usr/bin/sh, then
      .profile is invoked with an arg0 of -program by both login and su.

      All attempts to become another user using su are logged in the log file
      /var/adm/sulog.

EXAMPLES
      To become user bin while retaining your previously exported environment,
      execute:
            su bin

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




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su(1M)                UNIX System V(Essential Utilities)                 su(1M)


      To execute command with the temporary environment and permissions of user
      bin, type:
          su - bin -c "command args"

FILES
      /etc/passwd system's password file
      /etc/profilesystem's profile
      $HOME/.profileuser's profile
      /var/adm/suloglog file
      /etc/default/suthe default parameters that live here are:

                  SULOG:
                        If defined, all attempts to su to
                        another user are logged in the indicated file.

                  CONSOLE:
                        If defined, all attempts to suroot
                        are logged on the console.

                  PATH: Default path.

                  SUPATH:
                        Default path for a user invoking suroot.

SEE ALSO
      env(1), login(1), sh(1) in the User's Reference Manual.
      passwd(4), profile(4), environ(5) in the Programmer's Reference Manual.



























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