# Audio File Global Info Properties Access these properties using the functions described in Working with Global Information. ## Discussion A *specifier*, in the context of one of these properties, is a pointer to a buffer containing data specific to the property. Each property description names the type of the data required. You provide the data when accessing these properties using the functions described in Working with Global Information. ## Topics ### Constants [`var kAudioFileGlobalInfo_ReadableTypes: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_ReadableTypes) An array of `UInt32` values containing the file types (such as AIFF, WAVE, and so forth) that can be opened for reading. [`var kAudioFileGlobalInfo_WritableTypes: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_WritableTypes) An array of `UInt32` values containing the file types (such as AIFF, WAVE, and so forth) that can be opened for writing. [`var kAudioFileGlobalInfo_FileTypeName: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_FileTypeName) The name for the file type. [`var kAudioFileGlobalInfo_AvailableFormatIDs: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_AvailableFormatIDs) An array of format IDs for formats that can be read. [`var kAudioFileGlobalInfo_AvailableStreamDescriptionsForFormat: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_AvailableStreamDescriptionsForFormat) An array of audio stream basic description structures, which contain all the formats for a particular file type and format ID. [`var kAudioFileGlobalInfo_AllExtensions: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_AllExtensions) A `CFArray` of `CFStrings` containing all recognized file extensions. You can use this array when creating an `NSOpenPanel` (declared in the AppKit’s `NSOpenPanel.h` header file). [`var kAudioFileGlobalInfo_AllHFSTypeCodes: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_AllHFSTypeCodes) An array of HFS type codes containing all recognized HFS type codes. For more information on HFS type codes, see Audio Toolbox’s `ExtendedAudioFile.h` header file. [`var kAudioFileGlobalInfo_AllUTIs: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_AllUTIs) A `CFArray` of `CFString` of all UTIs (Universal Type Identifiers) recognized by Audio File Services. [`var kAudioFileGlobalInfo_AllMIMETypes: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_AllMIMETypes) A `CFArray` of CF strings of all MIME types are recognized by Audio File Services. [`var kAudioFileGlobalInfo_ExtensionsForType: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_ExtensionsForType) A `CFArray` of CF strings containing the recognized file extensions for a specified type. [`var kAudioFileGlobalInfo_HFSTypeCodesForType: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_HFSTypeCodesForType) An array of HFS type codes corresponding to a specified file type. The first type in the array is the preferred one to use. [`var kAudioFileGlobalInfo_UTIsForType: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_UTIsForType) A `CFArray` of `CFString` of all Universal Type Identifiers recognized by a specified file type. [`var kAudioFileGlobalInfo_MIMETypesForType: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_MIMETypesForType) A `CFArray` of `CFString` of all MIME types recognized by a specified file type. [`var kAudioFileGlobalInfo_TypesForExtension: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_TypesForExtension) An array of all audio file type IDs that support a specified filename extension. [`var kAudioFileGlobalInfo_TypesForHFSTypeCode: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_TypesForHFSTypeCode) An array of all audio file type IDs that support a specified `HFSTypeCode`. [`var kAudioFileGlobalInfo_TypesForUTI: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_TypesForUTI) An array of all audio file type IDs that support a specified UTI. [`var kAudioFileGlobalInfo_TypesForMIMEType: AudioFilePropertyID`](/documentation/AudioToolbox/kAudioFileGlobalInfo_TypesForMIMEType) An array of all audio file type IDs that support a specified MIME type. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)