2.2.4.1.3.82 UnPark

The UnPark packet is transmitted from a TAPI client to a TAPI server in a remote procedure call. Sending this packet retrieves the call that is parked at the specified address and returns a call handle for it.


0


1


2


3


4


5


6


7


8


9

1
0


1


2


3


4


5


6


7


8


9

2
0


1


2


3


4


5


6


7


8


9

3
0


1

Req_Func

Reserved1

dwRequestID

lpContext

hLine

dwAddressID

lphCallContext

lpszDestAddress

Reserved2

Reserved3

Reserved4

Reserved5

Reserved6

Reserved7

Reserved8

VarData (variable)

...

Req_Func (4 bytes): An unsigned 32-bit integer. The identifier of the function that will be invoked on the remote server. This value MUST be set to 90.

Return Values

On completion of ClientRequest, this field MUST contain the result of the encapsulated telephony request. A nonzero request ID value indicates that the request is in progress and will complete asynchronously, and a LINEERR_Constants value indicates synchronous failure.

Returns a positive request identifier if the function will be completed asynchronously or a negative error number if an error occurs. The dwParam2 parameter of the corresponding LINE_REPLY packet is zero if the function succeeds, or it is a negative error number if an error occurs. If the client specified a nonzero value in the dwRequestID field of the packet, the same value MUST be used for the returned positive request identifier. Common return values are:

Name

Value

LINEERR_INVALADDRESS

0x80000010

LINEERR_OPERATIONUNAVAIL

0x80000049

LINEERR_INVALADDRESSID

0x80000011

LINEERR_OPERATIONFAILED

0x80000048

LINEERR_INVALLINEHANDLE

0x8000002B

LINEERR_RESOURCEUNAVAIL

0x80000049

LINEERR_INVALPOINTER

0x80000035

LINEERR_UNINITIALIZED

0x80000050

LINEERR_NOMEM

0x80000044

Reserved1 (4 bytes): An unsigned 32-bit integer. MUST be set to zero when sent and MUST be ignored on receipt.

dwRequestID (4 bytes): An unsigned 32-bit integer. The identifier of the asynchronous request.

Value

Meaning

0x00000000

An unsigned 32-bit integer. The server MUST generate a unique positive request ID to return as the Ack_ReturnValue.

0x00000001 — 0x7FFFFFFF

The server MUST use this value instead of generating a unique positive request ID.

lpContext (4 bytes): An unsigned 32-bit integer. The opaque, client-specified value that is used by the client upon request completion; MUST be returned by the server in the request completion packet.

hLine (4 bytes): An HLINE. The handle to the open line device on which a call is to be unparked. This field MUST have been obtained by sending the Open packet. To park the call, the client needs to send a Park packet to the remote server.

dwAddressID (4 bytes): An unsigned 32-bit integer. The address on hLine at which the unpark is to be originated. An address identifier is permanently associated with an address; the identifier remains constant across operating system upgrades. A valid value of dwAddressID is in the range 0 to dwNumAddresses – 1. The client obtains dwNumAddresses from the LINEDEVCAPS obtained by sending a GetDevCaps packet to the remote server.

lphCallContext (4 bytes): An unsigned 32-bit integer. The opaque, client-specified value that is used by the client upon request completion; MUST be returned by the server in the request completion packet.

lpszDestAddress (4 bytes): An unsigned 32-bit integer. The offset, in bytes, in the VarData field of a null-terminated Unicode string that contains the address where the call is parked.

Reserved2 (4 bytes): An unsigned 32-bit integer. This field is used for padding and MUST be ignored on receipt. It can be any value.

Reserved3 (4 bytes): An unsigned 32-bit integer. This field is used for padding and MUST be ignored on receipt. It can be any value.

Reserved4 (4 bytes): An unsigned 32-bit integer. This field is used for padding and MUST be ignored on receipt. It can be any value.

Reserved5 (4 bytes): An unsigned 32-bit integer. This field is used for padding and MUST be ignored on receipt. It can be any value.

Reserved6 (4 bytes): An unsigned 32-bit integer. This field is used for padding and MUST be ignored on receipt. It can be any value.

Reserved7 (4 bytes): An unsigned 32-bit integer. This field is used for padding and MUST be ignored on receipt. It can be any value.

Reserved8 (4 bytes): An unsigned 32-bit integer. This field is used for padding and MUST be ignored on receipt. It can be any value.

VarData (variable): MUST contain a null-terminated Unicode string that is indicated by the lpszDestAddress.

The contents of this field are DWORD-aligned.