CPU(1)                                                     CPU(1)

     NAME
          cpu - connection to CPU server

     SYNOPSIS
          cpu [ -h server ] [ -u user ] [ -a auth-method ] [ -P
          patternfile ] [ -e encryption-hash-algs ] [ -k keypattern ]
          [ -c cmd args ... ]

          cpu [ -R | -O ]

     DESCRIPTION
          Cpu starts an rc(1) running on the server machine, or the
          machine named in the $cpu environment variable if there is
          no -h option.  Rc's standard input, output, and error files
          will be /dev/cons in the name space where the cpu command
          was invoked.  Normally, cpu is run in an rio(1) window on a
          terminal, so rc output goes to that window, and input comes
          from the keyboard when that window is current.  Rc's current
          directory is the working directory of the cpu command
          itself.

          The name space for the new rc is an analogue of the name
          space where the cpu command was invoked: it is the same
          except for architecture-dependent bindings such as /bin and
          the use of fast paths to file servers, if available.

          If a -u argument is present, cpu uses the argument as the
          remote user id.

          If a -c argument is present, the remainder of the command
          line is executed by rc on the server, and then cpu exits.

          If a -P argument is present, the patternfile is passed to
          exportfs(4) to control how much of the local name space will
          be exported to the remote system.

          The -a command allows the user to specify the authentication
          mechanism used when connecting to the remote system.  The
          two possibilities for auth-method are:

          p9      This is the default.  Authentication is done using
                  the standard Plan 9 mechanisms, (see authsrv(6)). No
                  user interaction is required.
          netkey  Authentication is done using challenge/response and
                  a hand held authenticator or the netkey program (see
                  passwd(1)). The user must encrypt the challenge and
                  type the encryption back to cpu. This is used if the
                  local host is in a different protection domain than
                  the server or if the user wants to log into the
                  server as a different user.

     Page 1                       Plan 9             (printed 3/28/24)

     CPU(1)                                                     CPU(1)

          The -e option specifies an encryption and/or hash algorithm
          to use for the connection.  If both are specified, they must
          be space separated and comprise a single argument, so they
          must be quoted if in a shell command.  The default is
          `rc4_256' encryption and `sha1' hashing.  See ssl(3) for
          details on possible algorithms.  The argument `clear' speci-
          fies no encryption algorithm and can be used to talk to
          older versions of the cpu service.

          The -k flag specifies a key pattern to use to restrict the
          keys selected by the auth_proxy call used for authentica-
          tion.

          The name space is built by running /usr/$user/lib/profile
          with the root of the invoking name space bound to /mnt/term.
          The service environment variable is set to cpu; the cputype
          and objtype environment variables reflect the server's
          architecture.

          The -R flag causes cpu to run the server (remote) side of
          the protocol.  It is run from service files such as
          /bin/service/tcp17010.  The -O flag is similar but simulates
          the pre-9P2000 version of the cpu protocol.

     FILES
          The name space of the terminal side of the cpu command is
          mounted, via exportfs(4), on the CPU side on directory
          /mnt/term.  The files such as /dev/cons are bound to their
          standard locations from there.

     SOURCE
          /sys/src/cmd/cpu.c

     SEE ALSO
          rc(1), rio(1), exportfs(4)

     BUGS
          Binds and mounts done after the terminal lib/profile is run
          are not reflected in the new name space.

          When using the -a option to `log in' as another user, be
          aware that resources in the local name space will be made
          available to that user.

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