Unique hardware ID in Mac OS X

Question

Mac OS X development is a fairly new animal for me, and I'm in the process of porting over some software. For software licensing and registration I need to be able to generate some kind of hardware ID. It doesn't have to be anything fancy; Ethernet MAC address, hard drive serial, CPU serial, something like that.

I've got it covered on Windows, but I haven't a clue on Mac. Any idea of what I need to do, or where I can go for information on this would be great!

Edit:

For anybody else that is interested in this, this is the code I ended up using with Qt's QProcess class:

QProcess proc;

QStringList args;
args << "-c" << "ioreg -rd1 -c IOPlatformExpertDevice |  awk '/IOPlatformUUID/ { print $3; }'";
proc.start( "/bin/bash", args );
proc.waitForFinished();

QString uID = proc.readAll();

Note: I'm using C++.

Answer 1

For C/C++:

void get_platform_uuid(char * buf, int bufSize) {
    io_registry_entry_t ioRegistryRoot = IORegistryEntryFromPath(kIOMasterPortDefault, "IOService:/");
    CFStringRef uuidCf = (CFStringRef) IORegistryEntryCreateCFProperty(ioRegistryRoot, CFSTR(kIOPlatformUUIDKey), kCFAllocatorDefault, 0);
    IOObjectRelease(ioRegistryRoot);
    CFStringGetCString(uuidCf, buf, bufSize, kCFStringEncodingMacRoman);
    CFRelease(uuidCf);    
}