Inside Macintosh: Networking /

Chapter 5 - AppleTalk Data Stream Protocol (ADSP) / ADSP Reference

Routines / Establishing and Terminating an ADSP Connection

dspClose

The dspClose routine closes a connection end. You use the PBControl function
to call the dspClose routine. See "Routines" on page 5-43 for a description of the PBControl function.

-->	ioCompletion	ProcPtr	A pointer to a completion routine.
<--	ioResult	OSErr	The function result.
-->	ioCRefNum	Integer	The driver reference number.
-->	csCode	Integer	Always dspClose for this function.
-->	ccbRefNum	Integer	The CCB reference number.
-->	abort	Byte	A value specifying to abort send requests if not 0.

Field Description

csCode

The routine selector, always equal to dspClose for this routine.

ccbRefNum

The connection control block (CCB) reference number that was returned by the dspNewCID routine for the connection end that
you want to close.

abort

A value that specifies whether or not to send all of the data in the send queue and all outstanding messages before closing the connection end. If the abort parameter is nonzero, ADSP cancels any outstanding requests to send data packets (such as the dspAttention routine) and discards all data in the send queue.
If the abort parameter is 0, ADSP does not close the connection
end until all of the data in the send queue and all outstanding attention messages have been sent and acknowledged.

DESCRIPTION

The dspClose routine closes the connection end. The connection end is still established; that is, ADSP retains ownership of the CCB, send queue, receive queue, and attention-
message buffer. You can continue to read bytes from the receive queue after you have called the dspClose routine. Use the dspRemove routine instead of the dspClose routine if you are finished with reading bytes from the receive queue and want to release the memory associated with the connection end.

SPECIAL CONSIDERATIONS

The dspClose routine does not return an error if you call it for a connection end that is already closed.

ASSEMBLY-LANGUAGE INFORMATION

To execute the dspClose routine from assembly language, call the _Control trap macro with a value of dspClose in the csCode field of the parameter block.

RESULT CODES

noErr	0	No error
errRefNum	-1280	Bad connection reference number

SEE ALSO

For information on how to remove a connection end and release the memory associated with it, see the description of the dspRemove routine that follows.