su(1M)            MISC. REFERENCE MANUAL PAGES             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  speci-
     fied  [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 pro-
     grams such as sh, an arg of  the  form  -c  string  executes
     string  via the shell and an arg of -r gives the user a res-
     tricted shell.

     The following statements are true only if the optional  pro-
     gram  named in the shell field of the specified user's pass-
     word 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 /usr/local/bin:/usr/bin:/usr/ccs/bin:/sbin:/usr/sbin:
     /etc:/usr/ucb:/usr/amiga/bin:/usr/public/bin 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, respec-
     tively.  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:



                Last change: Essential Utilities                1

su(1M)            MISC. REFERENCE MANUAL PAGES             su(1M)



          su bin

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

     To execute command with the temporary environment  and  per-
     missions of user bin, type:

         su - bin -c "command args"

FILES
     /etc/passwd     system's password file
     /etc/profile    system's profile
     $HOME/.profile  user's profile
     /var/adm/sulog  log file
     /etc/default/su the 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 Refer-
     ence Manual.























                Last change: Essential Utilities                2