EMU(1E)                                                   EMU(1E)

          emu - Inferno emulator (hosted Inferno)

          emu [ -g Xsize x Ysize ] [ -cn ] [ -d daemon ] [-s] [ -p
          pool=maxsize ] [ -f font ] [ -r rootpath ] [-7] [ -C channel
          ] [ -S ] [ -v ] [ cmd [ arg ... ] ]

          Emu provides the Inferno emulation environment, otherwise
          known as `hosted Inferno'.  The emulator runs as an applica-
          tion under the machine's native operating system, and pro-
          vides system services and a Dis virtual machine for Inferno

          Emu starts an Inferno initialisation program
          /dis/emuinit.dis, whose path name is interpreted in the
          Inferno file name space, not in the native operating
          system's name space.  It in turn invokes the shell
          /dis/sh.dis by default or the optional cmd and its argu-
          ments.  If the -d option is specified, emu instead invokes
          daemon, turning the emu instance into an Inferno service
          process on the network, running the given daemon service or

          The emulator supports the following options:

          -cn  Unless specified otherwise by the module (see wm/rt in
               wm-misc(1)), emu uses an interpreter to execute Dis
               instructions.  Setting n to 1 (the default value is 0)
               makes the default behaviour to compile Dis into native
               instructions when a module is loaded, resulting in fas-
               ter execution but larger run-time size.  Setting n to
               values larger than 1 enables increasingly detailed
               traces of the compiler.

          -d daemon
               Run emu as a server, invoking daemon instead of
               /dis/emuinit.dis, and disabling input from cons (see

               Define screen width and height in pixels.  The default
               values are 640x480 and the minimum values are 64x48.
               Values smaller than the minimum or greater than the
               available display size are ignored.

               Specify the default font for the tk module.  The path
               is interpreted in the Inferno name space.  If

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     EMU(1E)                                                   EMU(1E)

               unspecified, the font variable has value

               Specify the host system directory that emu will serve
               as its root.  The default value is /usr/inferno on most
               systems, but \inferno on Windows.

          -s   Specify how the emulator deals with traps reported by
               the operating system.  By default, they suspend execu-
               tion of the offending thread within the virtual machine
               abstraction.  The -s option causes emu itself to trap,
               permitting debugging of the broken host operating sys-
               tem process that results when a trap occurs.  (This is
               intended to allow debugging of emu, not Inferno appli-

               Specify the maximum size in bytes of the named memory
               allocation pool.  The pools are:

               main    the general malloc arena

               heap    the Dis virtual machine heap

               image   image storage for the display

          -7   When host graphics is provided by X11, request a 7-bit
               colour map; use this option only if X11 refused to
               allow emu to configure the normal (default) 8-bit
               Inferno colour map.

          -C channel
               Use the given channel for the display, if possible.
               See image(6) for the full range of channel descriptors.
               For example, k8 gives 8 bit greyscale, and x8r8g8b8
               gives 24 bit colour on a PC.  The set of channels sup-
               ported is platform-dependent.

          -S   Force stylus input behaviour for Tk mouse events:
               motion events are received only when a button is down
               (just as a stylus produces no events until it touches
               the screen).  This option only affects the behaviour of
               Tk mouse events, it does not affect the behaviour of
               /dev/pointer as described in cons(3).

          -v   Print version data: edition and revision date.

          Options may also be set in the host operating system's envi-
          ronment variable EMU; they are overridden by options sup-
          plied on the command line.

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     EMU(1E)                                                   EMU(1E)

          Emu finds the host system directory that will serve as its
          Inferno root directory as the last value found as follows:
          it is the value built-in to the executable, by default; or
          the value of the host system's environment variable INFERNO;
          or the value of the environment variable ROOT; or the value
          of a -r option in the environment variable EMU; or the
          rootpath set by a -r option to the emu command itself.

          Emu sets several Inferno environment variables:

          cputype     host processor architecture: 386 (for any x86),
                      arm, mips, power (any Power or PowerPC), sparc,
                      and spim (little-endian MIPS).

          emuargs     arguments with which emu was invoked

          emuhost     host operating system type, such as: FreeBSD,
                      Irix, Linux, MacOSX, NetBSD, Nt (used for Win-
                      dows generally), OpenBSD, Plan9, Solaris and

          emuroot     name of directory in host file system that acts
                      as Inferno's root directory

          emuwdir     name in host file system of directory where emu
                      was invoked

          To start wm/logon directly:

               EMU='-g800x600 -c1'
               emu /dis/wm/wm.dis wm/logon -u inferno

          /dis/emuinit.dis  The default initialisation program.
          /dis/sh.dis       The default Inferno shell.


          limbo(1), wm-misc(1)

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