Objective C - Get DisplayProductID and DisplayVendorID in MacOS programmatically

Question

Regarding DisplayProductID and DisplayVendorID of Screen (Display), I can get the info from System Information and several commands in Terminal like this;

Display Product Name is different with DisplayProductID, It is just String.

$ defaults read /Library/Preferences/com.apple.windowserver.plist
{
    DisplayResolutionEnabled = 1;
    DisplaySets =     (
                (
                        {
                Active = 1;
                Depth = 4;
                DisplayID = 69731456;
                DisplayProductID = 40978;
                DisplaySerialNumber = 0;
                DisplayVendorID = 1552;
                Height = 1080;
                IODisplayLocation = "IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/P0P2@1/IOPCI2PCIBridge/GFX0@0/NVDA,Display-A@0/NVDA";
                IOFlags = 7;
                LimitsHeight = 1080;
                LimitsOriginX = 0;
                LimitsOriginY = 0;
                LimitsWidth = 1920;
                MirrorID = 0;
                Mirrored = 0;
                Mode =                 {
                    BitsPerPixel = 32;
                    BitsPerSample = 8;
                    DepthFormat = 4;
                    Height = 1080;
                    IODisplayModeID = "-2147479552";
                    IOFlags = 7;
                    Mode = 1;
                    PixelEncoding = "--------RRRRRRRRGGGGGGGGBBBBBBBB";
                    RefreshRate = 0;
                    SamplesPerPixel = 3;
                    UsableForDesktopGUI = 1;
                    Width = 1920;
                    kCGDisplayBytesPerRow = 7680;
                    kCGDisplayHorizontalResolution = 103;
                    kCGDisplayModeIsInterlaced = 0;
                    kCGDisplayModeIsSafeForHardware = 1;
                    kCGDisplayModeIsStretched = 0;
                    kCGDisplayModeIsTelevisionOutput = 0;
                    kCGDisplayModeIsUnavailable = 0;
                    kCGDisplayModeSuitableForUI = 1;
                    kCGDisplayPixelsHigh = 1080;
                    kCGDisplayPixelsWide = 1920;
                    kCGDisplayResolution = 1;
                    kCGDisplayVerticalResolution = 103;
                };
                OriginX = 0;
                OriginY = 0;
                PixelEncoding = "--------RRRRRRRRGGGGGGGGBBBBBBBB";
                Resolution = 1;
                Unit = 0;
                UnmirroredHeight = 1080;
                UnmirroredLimitsHeight = 1080;
                UnmirroredLimitsOriginX = 0;
                UnmirroredLimitsOriginY = 0;
                UnmirroredLimitsWidth = 1920;
                UnmirroredMode =                 {
                    BitsPerPixel = 32;
                    BitsPerSample = 8;
                    DepthFormat = 4;
                    Height = 1080;
                    IODisplayModeID = "-2147479552";
                    IOFlags = 7;
                    Mode = 1;
                    PixelEncoding = "--------RRRRRRRRGGGGGGGGBBBBBBBB";
                    RefreshRate = 0;
                    SamplesPerPixel = 3;
                    UsableForDesktopGUI = 1;
                    Width = 1920;
                    kCGDisplayBytesPerRow = 7680;
                    kCGDisplayHorizontalResolution = 103;
                    kCGDisplayModeIsInterlaced = 0;
                    kCGDisplayModeIsSafeForHardware = 1;
                    kCGDisplayModeIsStretched = 0;
                    kCGDisplayModeIsTelevisionOutput = 0;
                    kCGDisplayModeIsUnavailable = 0;
                    kCGDisplayModeSuitableForUI = 1;
                    kCGDisplayPixelsHigh = 1080;
                    kCGDisplayPixelsWide = 1920;
                    kCGDisplayResolution = 1;
                    kCGDisplayVerticalResolution = 103;
                };
                UnmirroredOriginX = 0;
                UnmirroredOriginY = 0;
                UnmirroredResolution = 1;
                UnmirroredWidth = 1920;
                Width = 1920;
            }
        )
    );
    ForceOldStyleMemoryManagement = 0;
}

But I want to get this DisplayProductID and DisplayVendorID in MacOS app programmatically (Objective C).

How can I read this plist file in Objective-C?

This file is encrypted, can't get data. Please let me know the way to get DisplayProductID and VendorID programmatically.

Answer 1

CGDisplayVendorNumber() and CGDisplayModelNumber() should return those values. Use CGMainDisplayID() to get the ID for the main display, or there are other functions to get a list of displays you can filter/iterate over if needed.