Important: The information in this document is obsolete and should not be used for new development.
DTInstallAfter defining the fields of a deferred task record, you can call the
DTInstallfunction to install the record into the deferred task queue.
FUNCTION DTInstall (dtTaskPtr: QElemPtr): OSErr;
- A pointer to a queue element to add to the deferred task queue.
DTInstallfunction adds the specified task record to the deferred task queue. Your application should fill in all fields of the task record except
Ordinarily, you call
DTInstallonly at interrupt time. The
DTInstallfunction does not actually execute the routine specified in the
dtAddrfield of the task record. Each system interrupt handler executes routines stored in the deferred task queue after reenabling interrupts. After a routine in the queue is executed, it is removed from the deferred task queue.
qTypefield of the task record is not set to
vTypErrand does not add the record to the queue. Otherwise,
ASSEMBLY-LANGUAGE INFORMATIONThe registers on entry and exit for
Registers on entry A0 Pointer to new queue entry
Registers on exit D0 Result code
To reduce overhead at interrupt time, instead of executing the
DTInstalltrap, you can load the jump vector
jDTInstallinto an address register other than A0 and execute a
JSRinstruction using that register.
noErr 0 No error vTypErr -2 Invalid
qTypevalue (must be