AudioServicesGetProperty(_:_:_:_:_:)
Gets a specified System Sound Services property value.
Declaration
func AudioServicesGetProperty(_ inPropertyID: AudioServicesPropertyID, _ inSpecifierSize: UInt32, _ inSpecifier: UnsafeRawPointer?, _ ioPropertyDataSize: UnsafeMutablePointer<UInt32>, _ outPropertyData: UnsafeMutableRawPointer?) -> OSStatusParameters
- inPropertyID:
The property whose value you want.
- inSpecifierSize:
The size of the buffer pointed to by the
inSpecifierparameter. Pass0if no specifier buffer is required. - inSpecifier:
A pointer to a specifier buffer, if such a buffer is required by the property about which you want information. Pass
NULLif no specifier is required. - ioPropertyDataSize:
On input, the size, in bytes, of the buffer pointed to by the
outPropertyDataparameter. Call the Audioservicesgetpropertyinfo(_:_:_:_:_:) function to find out the size required for this buffer. On output, the number of bytes written to the buffer. - outPropertyData:
On output, the property value.
Return Value
A result code.
Discussion
System Sound Services properties are listed and described in System Sound Services Property Identifiers.
Special Considerations
Some Core Audio property values are C types and others are Core Foundation objects.
If you call this function to retrieve a value that is a Core Foundation object, then this function—despite the use of “Get” in its name—duplicates the object. You are responsible for releasing the object, as described in The Create Rule in Memory Management Programming Guide for Core Foundation.