RSH(C)                                     UNIX System V



     Name
          rsh - invokes a restricted shell (command interpreter)


     Syntax
          rsh [ flags ] [ name [ arg1 ... ] ]


     Description
          rsh  is  a  restricted  version  of  the  standard   command
          interpreter  sh(C).   It  is  used to set up login names and
          execution   environments   whose   capabilities   are   more
          controlled than those of the standard shell.  The actions of
          rsh are identical to  those  of  sh,  except  that  changing
          directory with cd, setting the value of
          $PATH,  using  command   names   containing   slashes,   and
          redirecting output using > and >> are all disallowed.

          When invoked with  the  name  -rsh,  rsh  reads  the  user's
          .profile  (from $HOME/.profile).  It acts as the standard sh
          while  doing  this,  except  that  an  interrupt  causes  an
          immediate  exit,  instead  of  causing  a  return to command
          level.  The restrictions above are enforced  after  .profile
          is interpreted.

          When a command to  be  executed  is  found  to  be  a  shell
          procedure,  rsh  invokes  sh  to  execute  it.   Thus, it is
          possible to provide to the end user  shell  procedures  that
          have  access  to the full power of the standard shell, while
          restricting him to a limited menu of commands;  this  scheme
          assumes  that  the  end user does not have write and execute
          permissions in the same directory.

          The net effect of these rules is  that  the  writer  of  the
          .profile   has   complete  control  over  user  actions,  by
          performing guaranteed setup actions, then leaving  the  user
          in   an   appropriate  directory  (probably  not  the  login
          directory).

          rsh is actually just a link to sh and  any  flags  arguments
          are the same as for sh(C).

          The system  administrator  often  sets  up  a  directory  of
          commands that can be safely invoked by rsh.


     See Also
          sh(C), profile(M)


     (printed 8/24/89)                                  RSH(C)