NPA_CDM_Passthru
Sends a CDM message to a device in order to receive
status or diagnostic information about the device. It is used for
vendor-specific commands by NLM applications.
- Thread Context:Blocking
Syntax
LONG NPA_CDM_Passthru (
LONG *appReturnCode,
LONG deviceObjectID,
LONG function,
LONG parameter0,
LONG parameter1,
LONG parameter2,
LONG bufferLength,
void *buffer
);
Parameters
- appReturnCode
- (OUT) Value returned by the managing CDM during CDI_Complete_Message. It can be any LONG
value understood by both the application and the specific CDM, because NWPA
does not attempt to interpret this value during the context of NPA_CDM_Passthru.
- deviceObjectID
- (IN) Media Manager object ID for the device.
- function
- Must be either 0x1E or 0x3E.
- parameter0
- (IN) Application-specific. Corresponds to the field
of the same name in CDMMessageStruct and
is generally used for the same purpose. When you are communicating
with a custom CDM, use the unique Novell assigned module ID for
the target CDM. Upon request, Developer Services can assign a specific
ID to your vendor.
- parameter1
- (IN) Application-specific. Corresponds to the field
of the same name in CDMMessageStruct and
is generally used for the same purpose.
- parameter2
- (IN) Application-specific. Corresponds to the field
of the same name in CDMMessageStruct and
is generally used for the same purpose.
- bufferLength
- (IN) Application-specific. Typically, its value
indicates the length, in bytes, of buffer. If it
is in scatter/gather format, it contains the number of
entries in the scatter/gather request list. It corresponds
to the field of the same name in CDMMessageStruct.
- buffer
- (IN) Application-specific. Typically, it points
to the virtual address of the CDM message's data buffer. If it is
in scatter/gather format, it contains the virtual starting
address of the scatter/gather request list. The scatter/gather
list is generated by NWPA or a Media Manager application. Depending
upon if a read or write operation is occurring, the buffer is where
the data is read to or read from. It corresponds to the field of
the same name in CDMMessageStruct.
Return Values
The following table lists return values and descriptions.
Remarks
NPA_CDM_Passthru is used to send vendor-specific
requests to the managing CDM of a device. This command sends a request,
then returns when the request is complete.
The CDM must understand the parameters being sent, and take
the necessary action, including HACBs to the device if needed.