Emulator Configuration File
The emulator has a number of options that can be set through a configuration file
that is read at startup.  The emulator first looks for this file in ~/.xhomerrc.  If
that does not exist, it looks for xhomer.cfg, in the current directory.  If that is
not found either, it relies on built-in defaults.  In the configuration file, blank
lines and those starting with a "#" character are ignored.  Following is a listing of
all of the options and their default values, in the case that no configuration file
is found:

  screen = window

    Sets the initial screen mode.  Valid values are "window" and "full."

  window_position = 0, 0

    Sets window position hints that are passed to the X-server.  These are (x, y)
    coordinates of the upper left corner of the window, relative to the upper left
    corner of the screen.

  window_scale = 2

    Sets the vertical display stretch factor for windowed mode.

  full_scale = 3

    Sets the vertical display stretch factor for full-screen mode.

  screen_gamma = 10

    Sets the display gamma correction factor.  It is specified as an integer equal
    to ten times the desired gamma factor.  See the "Emulated Display" section for
    more information.

  pcm = on

    Turn this on to use a private colormap in color-indexed X-windows display modes.
    (These are typically 8-bit modes)  Valid values are "on" and "off."  Turning
    this option off will cause the emulator to share a colormap with other running
    X-windows applications, which could potentially lead to an inability to allocate
    needed colors.

  framebuffers = 0

    Sets the number of frame buffers to be used in full-screen mode.  Valid values
    are 0, 1, 2 or 3.  If 0 is specified, the number of frame buffers will be auto-
    detected.  See the "Emulated Display" section for more information.

  serial0 =
  serial1 =
  serial2 =
  serial3 =

    Defines up to four serial devices present in the host system that the emulator
    may access.  On a Linux system, common settings are "/dev/ttyS0" (for the first
    serial port) or "/dev/ttyS1" (for the second serial port).  It is also possible
    to specify the Linux parallel port driver ("/dev/lp").  However, this driver
    does not support write buffer occupancy reporting, and a workaround needs to
    be turned on (see the "lp_workaround" option, below).

  la50 = null

    Defines the serial device connected to the output of the la50 printer emulator.
    Valid values are "serial0," "serial1," "serial2," "serial3," or "null."

  la50_dpi = 300

    Sets the PCL print density for the la50 emulator.

  kb = lk201

    Defines the serial device connected to the emulated keyboard port.  Sensible
    values are "lk201," "serial0," "serial1," "serial2," or "serial3."

  ptr = null

    Defines the serial device connected to the emulated printer port.  Valid values
    are "la50," "serial0," "serial1," "serial2," "serial3," or "null."

  com = null

    Defines the serial device connected to the emulated communications port.  Valid
    values are "la50," "serial0," "serial1," "serial2," "serial3," or "null."

  rd_dir = ./

    Defines the directory that the emulator looks for hard disk images in.

  rx_dir = ./

    Defines the directory that the emulator looks for floppy disk images in.

  rd0 = pos32.rd

    Defines the name of the hard disk image file.

  rx0 = 

    Defines the name of the floppy disk image file for the first floppy drive.

  rx1 = 

    Defines the name of the floppy disk image file for the second floppy drive.

  force_year = -1

    If greater than -1, forces the year value that the real-time clock hardware
    returns.  Legal settings are integers from -1 to 99.  This may be useful
    with Pro operating systems with Y2K bugs (Venix, for example, refuses to
    take the time settings from the clock, if the year value is outside the
    range of 70-99).

  maint_mode = off

    Set this to "on" to simulate shorting pins 8 and 9 on the printer port.
    This will cause the maintenance terminal interface registers to become
    accessible to software running on the Pro.  Some software (for example,
    the 2.9BSD installation floppy) uses this to run an initial command
    interface over the printer port.

  int_throttle = off

    Set this to "on" to cause the emulator to throttle interrupts from the
    periodic interrupt source.  If the emulator is falling behind real-time
    operation, the interrupt rate will be increased.  If the Pro operating
    system has not serviced the previous interrupt by the time the next one
    is due, the emulator will delay generation of periodic interrupts, until
    the Pro operating system has caught up.  While the emulation itself is
    slightly less accurate in this mode, the real-time clock is more likely
    to maintain accurate time, especially on host systems which are too slow
    to achieve real-time Pro performance.  NOTE:  This is an EXPERIMENTAL
    feature.  Its affect on Pro operating systems is not fully understood.

  nine_workaround = off

    When used in DGA mode (full-screen), the #9 I128 X-server has a number of
    bugs.  Turning the "nine_workaround" variable on installs workarounds for
    these problems.  This option is specific to the #9 I128 X-server.  Valid
    values are "on" or "off."

  libc_workaround = off

    Turn this workaround on only if running on a pre-glibc-2.0 system.  The
    workaround prevents crashes during DGA-to-windowed mode switches.  Valid
    values are "on" or "off."  This workaround is not needed on modern Linux
    systems.

  lp_workaround = off

    Turn this workaround on if one of the emulator's serial ports is connected
    to a Linux parallel port device (/dev/lp).  See the description above for
    "serial0..3."

    Note that this workaround is somewhat crude.  When enabled, it applies to
    all serial devices (serial0..3), not just those with parallel ports
    connected.