Legacy Document

Important: The information in this document is obsolete and should not be used for new development.

Constants

You pass a selector code when you call Gestalt to specify the kind of information you need. Apple defines two distinct kinds of selector codes: environmental selectors, which supply information you can use to control the behavior of your application, and informational selectors, which supply information you can't use to determine what hardware or software features are available.

The selector code constants use a set of suffixes that indicate what format the response value will take. Selectors with the suffix Attr, for example, return a 32-bit response value in which the individual bits represent specific attributes. The constants listed for these response values represent bit numbers. For a more general description of selectors and their response values, see "Interpreting Gestalt Responses" beginning on page 1-9.

The Gestalt function accepts the following environmental selectors.

Selector	Response bits and response values
gestaltAddressingModeAttr	Current addressing-mode attributes.
	CONST gestalt32BitAddressing = 0; gestalt32BitSysZone = 1; gestalt32BitCapable = 2;
	The `gestalt32BitAddressing` attribute indicates that the machine started up with 32-bit addressing. The `gestalt32BitSysZone` attribute indicates that the system heap has 32-bit clean block headers (regardless of the type of addressing the machine started up in). See the book Inside Macintosh: Memory for more information about 32-bit addressing.
gestaltAliasMgrAttr	Alias Manager attributes.
	CONST gestaltAliasMgrPresent = 0; gestaltAliasMgrSupportsRemoteAppleTalk = 1;
gestaltAppleEventsAttr	The Apple events attribute.
	CONST gestaltAppleEventsPresent = 0; gestaltScriptingSupport = 1; gestaltOSLInSystem = 2;
gestaltAppleTalkVersion	The version number of the AppleTalk driver (in particular, the .MPP driver) currently installed. The version number is placed into the low-order byte of the result; ignore the three high-order bytes. If an AppleTalk driver is not currently open, the `response` parameter is 0.
gestaltATalkVersion	The version number of the AppleTalk driver, in the format introduced with AppleTalk version 56. (For a description of AppleTalk, see Inside AppleTalk, second edition.) The version is stored in the high 3 bytes of the return value.
	Byte 3 contains the major revision number, byte 2 contains the minor revision number, and byte 1 contains a constant that represents the release stage.
`gestaltATalkVersion`	`CONST development = $20; alpha = $40; beta = $60; final = $80; release = $80;`
	For example, if you call `Gestalt` with the `'atkv'` selector when AppleTalk version 57 is loaded, you receive the long integer response value `$39008000`. Byte 0 always contains 0.
gestaltAUXVersion	The version of A/UX if it is currently executing. The result is placed into the low-order word of the `response` parameter. If A/UX is not executing, `Gestalt` returns `gestaltUnknownErr`.
gestaltCFMAttr	Code Fragment Manager attributes.
	CONST gestaltCFMPresent = 0;
gestaltCloseViewAttr	The CloseView attributes
	CONST gestaltCloseViewEnabled = 0; gestaltCloseViewDisplayMgrFriendly = 1;
getstaltComponentMgr	The version of the Component Manager.
getstaltCompressionMgr	The version of the Image Compression Manager.
gestaltConnMgrAttr	Connection Manager attributes.
	CONST gestaltConnMgrPresent = 0; gestaltConnMgrCMSearchFix = 1; gestaltConnMgrErrorString = 2; gestaltConnMgrMultiAsyncIO = 3;
	The `gestaltConnMgrCMSearchFix` bit flag indicates that the fix is present that allows the `CMAddSearch` routine to work over the `mAttn` channel.
gestaltCRMAttr	Communications Resource Manager attributes.
	CONST gestaltCRMPresent = 0; gestaltCRMPersistentFix = 1; gestaltCRMToolRsrcCalls = 2;
gestaltCTBVersion	The version number of the Communications Toolbox (in the low-order word of the return value).
gestaltDBAccessMgrAttr	The Data Access Manager attribute.
	CONST gestaltDBAccessMgrPresent = 0;
gestaltDictionaryMgrAttr	The Dictionary Manager attributes.
	CONST gestaltDictionaryMgrPresent = 0;
gestaltDisplayMgrAttr	The Display Manager attributes.
	CONST gestaltDisplayMgrPresent = 0;
gestaltDITLExtAttr	The Dialog Manager extensions attributes.
	CONST gestaltDITLExtPresent = 0;
	If this flag bit is `TRUE`, then the Dialog Manager extensions included in System 7 are available. See the book Inside Macintosh: Macintosh Toolbox Essentials for details about the Dialog Manager.
gestaltDragMgrAttr	Drag Manager attributes.
	CONST gestaltDragMgrPresent = 0;
gestaltEasyAccessAttr	Easy Access attributes.
	CONST gestaltEasyAccessOff = 0; gestaltEasyAccessOn = 1; gestaltEasyAccessSticky = 2; gestaltEasyAccessLocked = 3;
gestaltEditionMgrAttr	Edition Manager attributes.
	CONST gestaltEditionMgrPresent = 0; gestaltEditionMgrTranslationAware = 1 ;
gestaltExtToolboxTable	The base address of the second half of the Toolbox trap table if the table is discontiguous. If the table is contiguous, this selector returns 0.
gestaltFinderAttr	Finder attributes.
	CONST gestaltFinderDropEvent = 0; gestaltFinderMagicPlacement = 1; gestaltFinderCallsAEProcess = 2; gestaltOSLCompliantFinder = 3; gestaltFinderS upports4GBVolumes = 4; gestaltFinderHandlesCFMFailures = 5; gestaltFinderHasClippings = 6;
gestaltFindFolderAttr	The `FindFolder` function attribute.
	CONST gestaltFindFolderPresent = 0;
gestaltFirstSlotNumber	The first physical slot.
gestaltFontMgrAttr	The Font Manager attribute.
	CONST gestaltOutlineFonts = 0;
gestaltFPUType	A constant that represents the type of floating-point unit currently installed, if any.
	CONST gestaltNoFPU = 0; gestalt68881 = 1; gestalt68882 = 2; gestalt68040FPU = 3;
gestaltFSAttr	File system attributes.
	CONST gestaltFullExtFSDispatching = 0; gestaltHasFSSpecCalls = 1; gestaltHasFileSystemManager = 2; gestaltFSMDoesDynamicLoad = 3; gestaltFSSupports4GBVols = 4; gestaltHasExtendedDiskInit = 6;
gestaltFXfrMgrAttr	The File Transfer Manager attributes.
	CONST gestaltFXfrMgrPresent = 0; gestaltFXfrMgrMultiFile = 1; gestaltFXfrMgrErrorString = 2;
gestaltHelpMgrAttr	The Help Manager attribute.
	CONST gestaltHelpMgrPresent = 0;
gestaltIconUtilitiesAttr	The Icon Utilities attribute.
	CONST gestaltIconUtilitiesPresent = 0;
gestaltKeyboardType	A constant that represents the type of keyboard.
	CONST gestaltMacKbd = 1; gestaltMacAndPad = 2; gestaltMacPlusKbd = 3; gestaltExtADBKbd = 4; gestaltStdADBKbd = 5; gestaltPrtblADBKbd = 6; gestaltPrtblISOKbd = 7;
`gestaltKeyboardType`	gestaltStdISOADBKbd = 8; gestaltExtISOADBKbd = 9; gestaltADBKbdII = 10; gestaltADBISOKbdII = 11; gestaltPwrBookADBKbd = 12; gestaltPwrBookISOADBKbd = 13; gestaltAppleAdjustKeypad = 14; gestaltAppleAdjustADBKbd = 15; gestaltAppleAdjustISOKbd = 16;
	If the Apple Desktop Bus (ADB) is in use, there may be multiple keyboards or other ADB devices attached to the machine. The gestaltKeyboardType selector identifies only the type of the keyboard on which the last keystroke occurred. You cannot use this selector to find out what ADB devices are connected. For that, you can use the Apple Desktop Bus Manager, described in Inside Macintosh: Devices. Note that the ADB keyboard types described by `Gestalt` do not necessarily map directly to ADB device handler IDs. Future support for the `gestaltKeyboardType` selector is not guaranteed. To determine the type of the keyboard last touched without using `Gestalt`, check the system global variable `KbdType`, documented in Inside Macintosh: Devices.
	If the Gestalt Manager does not recognize the keyboard type, it returns an error.
gestaltLogicalPageSize	The logical page size. This value is defined only on machines with the MC68010, MC68020, MC68030, or MC68040 microprocessors. On a machine with the MC68000, `Gestalt` returns an error when called with this selector.
gestaltLogicalRAMSize	The amount of logical memory available. This value is the same as that returned by `gestaltPhysicalRAMSize` when virtual memory is not installed. On some machines, however, this value might be less than the value returned by `gestaltPhysicalRAMSize` because some RAM may be used by the video display and the Operating System.
gestaltLowMemorySize	The size (in bytes) of the low-memory area. The low-memory area is used for vectors, global variables, and dispatch tables.
gestaltMiscAttr	Information about miscellaneous pieces of the Operating System or hardware configuration.
	CONST gestaltScrollingThrottle = 0; gestaltSquareMenuBar = 2;
gestaltMixedModeVersion	The version of Mixed Mode Manager.
gestaltMMUType	A constant that represents the type of MMU currently installed.
	CONST gestaltNoMMU = 0; gestaltAMU = 1; gestalt68851 = 2; gestalt68030MMU = 3; gestalt68040MMU = 4; gestaltEMMU1 = 5;
gestaltNativeCPUtype	Native CPU type.
	CONST gestaltCPU68000 = $000; gestaltCPU68010 = $001; gestaltCPU68020 = $002; gestaltCPU68030 = $003; gestaltCPU68040 = $004; gestaltCPU601 = $101;
	Note, to check whether the native system architecture is a MC680x0 or a PowerPC microprocessor, use the `gestaltSysArchitecture` selector.
gestaltNotificationMgrAttr	The Notification Manager attribute.
	CONST gestaltNotificationPresent = 0;
gestaltNuBusConnectors	A bitmap that describes the NuBus\xC5 slot connector locations. On a Macintosh II, for example, the return value would have bits 9 through 14 set, indicating that 6 NuBus slots are present, at locations 9 through 14.
gestaltOSAttr	General Operating System attributes, such as whether temporary memory handles are real handles. The low-order bits of the `response` parameter are interpreted as bit flags. A flag is set to 1 to indicate that the corresponding feature is available. Currently, the following bits are significant:
`gestaltOSAttr`	CONST gestaltSysZoneGrowable = 0; gestaltLaunchCanReturn = 1; gestaltLaunchFullFileSpec = 2; gestaltLaunchControl = 3; gestaltTempMemSupport = 4; gestaltRealTempMemory = 5; gestaltTempMemTracked = 6 ;
	See the book Inside Macintosh: Memory for a full explanation of the temporary memory features, and see the book Inside Macintosh: Processes for a full explanation of the launch control features.
gestaltOSTable	The base address of the Operating System trap dispatch table.
gestaltParityAttr	Information about the machine's parity-checking features.
	CONST gestaltHasParityCapability = 0; gestaltParityEnabled = 1;
	Note that parity is not considered to be enabled unless all installed memory is parity RAM.
gestaltPCXAttr	PC Exchange attributes.
	CONST gestaltPCXHas8and16BitFAT = 0; gestaltPCXHasProDOS = 1;
gestaltPhysicalRAMSize	The number of bytes of physical RAM currently installed.
gestaltPopupAttr	The attribute of the pop-up control definition.
	CONST gestaltPopupPresent = 0;
gestaltPowerMgrAttr	Power Manager attributes.
	CONST gestaltPMgrExists = 0; gestaltPMgrCPUIdle = 1; gestaltPMgrSCC = 2; gestaltPMgrSound = 3; gestaltPMgrDispatchExists = 4;
gestaltPPCToolboxAttr	Program-to-Program Communication (PPC) Toolbox attributes. Note that these constants are defined as masks, not bit numbers.
	CONST gestaltPPCToolboxPresent = $0000; gestaltPPCSupportsRealTime = $1000; gestaltPPCSupportsIncoming = $0001; gestaltPPCSupportsOutgoing = $0002;
gestaltProcessorType	A constant that represents the type of microprocessor currently running.
	CONST gestalt68000 = 1; gestalt68010 = 2; gestalt68020 = 3; gestalt68030 = 4; gestalt68040 = 5;
gestaltQuickdrawFeatures	QuickDraw features. CONST gestaltHasColor = 0; gestaltHasDeepGWorlds = 1; gestaltHasDirectPixMaps = 2; gestaltHasGrayishTextOr = 3; gestaltSupportsMirroring = 4;
gestaltQuickdrawVersion	The version of QuickDraw, encoded as a revision number in the low-order word of the return value. The high-order byte represents the major revision number, and the low-order byte represents the minor revision number. For example, version 1.3 of 32-Bit QuickDraw represents QuickDraw revision 2.3; its `response` value is `$0230`.
	CONST gestaltOriginalQD = $000; gestalt8BitQD = $100; gestalt32BitQD = $200; gestalt32BitQD11 = $210; gestalt32BitQD12 = $220; gestalt32BitQD13 = $230;
	Values having a major revision number of 1 or 2 indicate that Color QuickDraw is available, in either the 8-bit or 32-bit version. These results do not, however, indicate whether a color monitor is attached to the system. You must use high-level QuickDraw routines to obtain that information.
gestaltQuickTimeVersion	The QuickTime version.
gestaltRealtimeMgrAttr	Realtime Manager attributes.
	CONST gestaltRealtimeMgrPresent = 0;
gestaltResourceMgrAttr	The Resource Manager attribute.
	CONST gestaltPartialRsrcs = 0;
gestaltScrapMgrAttr	Scrap Manager attributes.
	`CONST gestaltScrapMgrTranslationAware` `= 0;` gestaltTranslationMgrHintOrder = 1;
gestaltScriptCount	The number of script systems currently active.
gestaltScriptMgrVersion	The version number of the Script Manager (in the low-order word of the return value).
gestaltSerialAttr	Serial hardware attributes of the machine, such as whether or not the GPIa line is connected and can be used for external clocking.
	CONST gestaltHasGPIaToDCDa = 0; gestaltHasGPIaToRTxCa = 1; gestaltHasGPIaToDCDb = 2;
gestaltSlotAttr	Slot Manager attributes.
	CONST gestaltSlotMgrExists = 0; gestaltNuBusPresent = 1; gestaltSESlotPresent = 2; gestaltSE30SlotPresent = 3; gestaltPortableSlotPresent = 4;
gestaltSoundAttr	Sound attributes.
	CONST gestaltStereoCapability = 0; gestaltStereoMixing = 1; gestaltSoundIOMgrPresent = 3; gestaltBuiltInSoundInput = 4; gestaltHasSoundInputDevice = 5; gestaltPlayAndRecord = 6; gestalt16BitSoundIO = 7; gestaltStereoInput = 8; gestaltLineLevelInput = 9; gestaltSndPlayDoubleBuffer = 10; gestaltMultiChannels = 11 gestalt16BitAudioSupport = 12 ;
`gestaltSoundAttr`	If the bit `gestaltStereoCapability` is `TRUE`, the available hardware can play stereo sounds. The bit `gestaltStereoMixing` indicates that the sound hardware of the machine mixes both left and right channels of stereo sound into a single audio signal for the internal speaker. The `gestaltSoundIOMgrPresent` bit indicates that the new sound input routines are available, and the `gestaltBuiltInSoundInput` bit indicates that a built-in sound input device is available. The `gestaltHasSoundInputDevice` bit indicates that some sound input device is available. Note, bits 7 through 12 are not defined for versions of the Sound Manager prior to version 3.0.
gestaltSpeechAttr	Speech Manager attributes.
	`CONST`getaltSpeechMgrPresent = 0; getaltSpeechHasPPCGlue = 1;
gestaltStandardFileAttr	Standard File Package attributes.
	`CONST`gestaltStandardFile58`= 0; gestaltStandardFileTranslationAware = 1; gestaltStandardFileHasColorIcons = 2;`
	If the `gestaltStandardFile58` flag bit is set, you can call the four new procedures--`StandardPutFile`, `StandardGetFile`, `CustomPutFile`, and `CustomGetFile`--introduced with System 7. (The name of the constant reflects the enabling of selectors 5 through 8 on the trap macro that handles the Standard File Package.)
gestaltStdNBPAttr	Information about the `StandardNBP` (Name-Binding Protocol) function.
	CONST gestaltStdNBPPresent = 0;
gestaltSysArchitecture	The native system architecture.
	CONST gestalt68k = 1; gestaltPowerPC = 2;
	If the `gestalt68k` flag bit is set, the native microprocessor is a MC680x0 chip. If the `gestaltPowerPC` flag bit is set, the native microprocessor is a PowerPC chip.
gestaltTEAttr	TextEdit attributes.
	CONST gestaltTEHasGetHiliteRgn = 0;
gestaltTermMgrAttr	Terminal Manager attributes.
	CONST gestaltTermMgrPresent = 0; gestaltTermMgrErrorString = 2;
gestaltTextEditVersion	A constant that indicates which version of TextEdit is present.
	CONST gestaltTE1 = 1; gestaltTE2 = 2; gestaltTE3 = 3; gestaltTE4 = 4; gestaltTE5 = 5;
gestaltThreadMgrAtt	Thread Manager attributes.
	CONST gestaltThreadMgrPresent = 0; gestaltSpecificMatchSupport = 1;
gestaltTimeMgrVersion	A constant that indicates which version of the Time Manager is present.
	CONST gestaltStandardTimeMgr = 1; gestaltRevisedTimeMgr = 2; gestaltExtendedTimeMgr = 3;
gestaltToolboxTable	The base address of the Toolbox trap dispatch table.
gestaltTranslationAttr	The Translation Manager attributes.
	CONST gestaltTranslationMgrExists = 0;
gestaltTSMgrVersion	The version of the Text Services.
gestaltVersion	The version of the Gestalt Manager (in the low-order word of the return value). The current version is 1, corresponding to a returned value of $0001.
gestaltVMAttr	The virtual memory attributes.
	CONST gestaltVMPresent = 0;

The Gestalt function also accepts the following informational selectors.

WARNING

Never infer the existence of certain hardware or software features from the responses that Gestalt returns when you pass it an informational selector.

Selector	Meaning
gestaltHardwareAttr	Low-level hardware configuration attributes.
	CONST gestaltHasVIA1 = 0; gestaltHasVIA2 = 1; gestaltHasASC = 3; gestaltHasSCC = 4; gestaltHasSCSI = 7; gestaltHasSoftPowerOff = 19; gestaltHasSCSI961 = 21; gestaltHasSCSI962 = 22; gestaltHasUniversalROM = 24;
	The `gestaltHasSCSI` bit means the machine is equipped with a SCSI implementation based on the 53C80 chip, which was introduced in the Macintosh Plus. This bit is 0 on computers with a different SCSI implementation. Those computers set the `gestaltHasSCSI961` or `gestaltHasSCSI962` bit to report a SCSI implementation based on the 53C96 chip installed on an internal or external bus, respectively. The `gestaltHasSCC` bit is normally returned as 0 on the Macintosh IIfx and Macintosh Quadra 900 computers, which have intelligent I/O processors that isolate the hardware and make direct access to the SCC impossible. However, if the user has used the Compatibility Switch control panel to enable compatibility mode, `gestaltHasSCC` is set.
gestaltMachineIcon	The icon family resource ID for the current type of Macintosh.
gestaltMachineType	A constant that indicates the model of computer.
	CONST gestaltClassic = 1; gestaltMacXL = 2; gestaltMac512KE = 3; gestaltMacPlus = 4; gestaltMacSE = 5; gestaltMacII = 6; gestaltMacIIx = 7; gestaltMacIIcx = 8; gestaltMacSE030 = 9; gestaltPortable = 10;
`gestaltMachineType`	gestaltMacIIci = 11; gestaltMacIIfx = 13; gestaltMacClassic = 17; gestaltMacIIsi = 18; gestaltMacLC = 19; gestaltQuadra900 = 20; gestaltPowerBook170 = 21; gestaltQuadra700 = 22; gestaltClassicII = 23; gestaltPowerBook100 = 24; gestaltPowerBook140 = 25; gestaltQuadra950 = 26; gestaltMacLCIII = 27; gestaltPowerBookDuo210 = 29; gestaltMacCentris650 = 30; gestaltPowerBookDuo230 = 32; gestaltPowerBook180 = 33; gestaltPowerBook160 = 34; gestaltMacQuadra800 = 35; gestaltMacLCII = 37; gestaltPowerBookDuo250 = 38; gestaltMacIIvi = 44; gestaltPerforma600 = 45; gestaltMacIIvx = 48; gestaltMacColorClassic = 49; gestaltPowerBook165c = 50; gestaltMacCentris610 = 52; gestaltMacQuadra610 = 53; gestaltPowerBook145 = 54; gestaltMacLC520 = 56; gestaltMacCentris660AV = 60; gestaltPowerBook180c = 71; gestaltPowerBookDuo270c = 77; gestaltMacQuadra840AV = 78; gestaltPowerBook165 = 84; gestaltMacTV = 88; gestaltMacLC475 = 89; gestaltMacLC575 = 92; gestaltMacQuadra605 = 94; gestaltPowerMac8100_80 = 65; gestaltPowerMac6100_60 = 75; gestaltPowerMac7100_66 = 112;
	To obtain a string containing the machine's name, you can pass the returned value to the `GetIndString` procedure as an index into the resource of type `'STR#'` in the System file having the resource ID defined by the constant kMachineNameStrID.
	CONST kMachineNameStrID = -16395;
`gestaltROMSize`	The size of the installed ROM, in bytes. The value is returned in only one word.
`gestaltROMVersion`	The version number of the installed ROM (in the low-order word of the return value).
gestaltSystemVersion	The version number of the currently active System file, represented as four hexadecimal digits in the low-order word of the return value. For example, if your application is running in version 7.0.1, then `Gestalt` returns the value $0701. Ignore the high-order word of the returned value.

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