Inside Macintosh: Interapplication Communication /

Chapter 4 - Responding to Apple Events / Reference to Responding to Apple Events

Routines for Responding to Apple Events / Getting the Sizes and Descriptor Types of Descriptor Records

AESizeOfParam

You can use the AESizeOfParam function to get the size and descriptor type of an Apple event parameter.

FUNCTION AESizeOfParam (theAppleEvent: AppleEvent; theAEKeyword: 
                        AEKeyword; VAR typeCode: DescType; 
                        VAR dataSize: Size): OSErr;

theAppleEvent

The Apple event containing the parameter.

theAEKeyword

The keyword that specifies the desired parameter.

typeCode

The descriptor type of the Apple event parameter.

dataSize

The length, in bytes, of the data in the Apple event parameter.

RESULT CODES

noErr	0	No error
errAEDescNotFound	-1701	Descriptor record was not found
errAENotAEDesc	-1704	Not a valid descriptor record
errAEReplyNotArrived	-1718	Reply has not yet arrived