AudioFileCountUserData(_:_:_:)

Declaration

func AudioFileCountUserData(_ inAudioFile: AudioFileID, _ inUserDataID: UInt32, _ outNumberItems: UnsafeMutablePointer<UInt32>) -> OSStatus

Parameters

• inAudioFile:

  The audio file whose user data items are to be counted.

• inUserDataID:

  The four-character code (such as COMM) of the user data item.

• outNumberItems:

  On output, a pointer to the number of user data items of this type in the file.

Return Value

A result code if there’s an error (see Result Codes) or noErr if the operation succeeds.

Discussion

In this function, user data refers to:

• Chunks in AIFF, CAF, and WAVE files

• Resources in Sound Designer II files

• Other types of information in other files

See Also

Working with User Data

• AudioFileGetUserDataSize(_:_:_:_:)
• AudioFileGetUserDataSize64(_:_:_:_:)
• AudioFileGetUserData(_:_:_:_:_:)
• AudioFileGetUserDataAtOffset(_:_:_:_:_:_:)
• AudioFileSetUserData(_:_:_:_:_:)
• AudioFileRemoveUserData(_:_:_:)