EMU(1E) EMU(1E)
NAME
emu - Inferno emulator
SYNOPSIS
emu [ -gXsizexYsize ] [ -c[0-9] ] [ -d[012] ] [ -m[0-9] ]
[-s] [ -ppool=maxsize ] [ -ffont ] [ -rrootpath ] [-7] [-2]
[-d] [ cmd [ arg ... ] ]
DESCRIPTION
Emu provides the Inferno emulation environment. The emula-
tor runs as an application under the machine's native oper-
ating system, and provides system services and a Dis virtual
machine for Inferno applications.
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
/dis/lib/srv.dis, turning the emu instance into an Inferno
service process on the network (see srv(8)).
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.
-gXsizexYsize
Define screen width and height in pixels. The default
values are 640 and 480 respectively. Values smaller
than the defaults are disallowed.
-ffont
Specify the default font for the tk module. The path
is interpreted in the Inferno name space. If unspeci-
fied, the font variable has value
/fonts/lucm/unicode.9.font.
-rrootpath
Specify the host system directory that emu will serve
as its root. The default value is /usr/inferno on most
systems, but \users\inferno on Windows.
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EMU(1E) EMU(1E)
-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-
cations.)
-ppool=maxsize
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.
-2 Use greyscale (Windows only).
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.
EXAMPLE
To start wm/logon directly:
EMU='-g800x600 -c1'
emu /wm/logon.dis -u inferno
FILES
/dis/emuinit.dis The default initialisation program.
/dis/sh.dis The default Inferno shell.
SOURCE
/emu
SEE ALSO
limbo(1), wm-misc(1)
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