Specifications

CHAPTER 4
Software Support
Gestalt Selector 79
pc (pc followed by two spaces). Only 4 bits of the word are currently in use, as shown
below. The remaining 28 bits are undefined.
gestaltDOSCompatibleState = pc
enum {
gestaltPCInstalled,
gestaltPCRunning,
gestaltPCHasTakenOver,
gestaltPCSharingMonitor
};
Field descriptions
gestaltPCInstalled
This is bit 0. If it is high, the PC Setup Init has been run and is
installed.
gestaltPCRunning
This is bit 1. It tells the caller whether or not the PC system is
running. If the bit is high, the PC system is running.
gestaltPCHasTakenOver
This is bit 2. It tells the caller whether or not the PC system is in the
foreground. If the bit is high, the PC system is in the foreground,
and you are running applications on the PC system rather than the
Mac OS. You may see physical signs of this condition. For example,
if you have a shared monitor, the PC screen will replace the
Macintosh screen. If you have two monitors, the Macintosh screen
will dim when the PC system is in the foreground.
gestaltPCSharingMonitor
This is bit 3. It tells the caller whether or not the system is set up
with a dedicated monitor for the PC system. If the bit is high, there
is no dedicated monitor for the PC system.