Carbon


Keyword Parameter Constants

Header: AppleEvents.h

Specify keyword values for Apple event parameters, as well as information for the AEManagerInfo function to retrieve. Some common key word values are shown here.

enum {
    keyDirectObject = '----',
    keyErrorNumber = 'errn',
    keyErrorString = 'errs',
    keyProcessSerialNumber = 'psn ',
    keyPreDispatch = 'phac',
    keySelectProc = 'selh',
    keyAERecorderCount = 'recr',
    keyAEVersion = 'vers'
};

Constant descriptions

keyDirectObject

Direct parameter. Usually specifies the data to be acted upon by the target application.

keyErrorNumber

Error number. Often used to extract error information from a reply Apple event.

keyErrorString

Error string. Often used to extract error information from a reply Apple event to display to the user.

keyProcessSerialNumber

Process serial number. See also “AEAddressDesc”.

keyPreDispatch

A predispatch handler (an Apple event handler that the Apple Event Manager calls immediately before it dispatches an Apple event). See also “Managing Special Handler Dispatch Tables”.

keySelectProc

You pass this value in the functionClass parameter of the AERemoveSpecialHandler function to disable the Object Support Library. Disabling the Object Support Library is not recommended for Carbon Applications.

keyAERecorderCount

Used with the keyword parameter of the AEManagerInfo function. If you pass this value, on return, the result parameter supplies the number of processes that are currently recording Apple events.

Available with version 1.0.1 and later.

keyAEVersion

Used with the keyword parameter of the AEManagerInfo function. If you pass this value, on return, the result parameter supplies version information for the Apple Event Manager, in NumVersion format.

Available with version 1.0.1 and later.

These constants are keyword constants for Apple event parameters. An Apple event consists of attributes (which identify the Apple event and denote its task) and, often, parameters (which contain information to be used by the target application). Taken together, the attributes of an Apple event denote the task to be performed on any data specified in the Apple event’s parameters.

Keywords are arbitrary names used by the Apple Event Manager to keep track of various descriptor records. Your application cannot examine the contents of an Apple event directly. Instead, you call Apple Event Manager routines such as those described in “Getting Data or Descriptor Records From Apple Event Parameters and Attributes” to request attributes and parameters by keyword.

See also “Keyword Attribute Constants”.


© 2000 Apple Computer, Inc. (Last Updated 6/30/2000)