WSD_APP_SEQUENCE structure (wsdtypes.h)
Represents application sequence information relating to WS-Discovery messages.
Syntax
typedef struct _WSD_APP_SEQUENCE {
ULONGLONG InstanceId;
const WCHAR *SequenceId;
ULONGLONG MessageNumber;
} WSD_APP_SEQUENCE;
Members
InstanceId
The instance identifier.
SequenceId
The sequence identifier.
MessageNumber
The message number.
Remarks
The application sequencing header block allows a receiver to maintain the sequence messages that contain this header block though they may have been received out of order. This allows proper sequencing of Hello and Bye messages from a target service.
The normative outline for the application sequence header block is:
<s:Envelope ...>
<s:Header ...>
<d:AppSequence InstanceId='xs:nonNegativeInteger' [SequenceId='xs:anyURI']? MessageNumber='xs:nonNegativeInteger' ... />
</s:Header>
<s:Body ...> ...
</s:Body>
</s:Envelope>
The following describes normative constraints of this outline.
/s:Envelope/s:Header/d:AppSequence/@InstanceId
This setting must be incremented by a value of at least 1 each time the service has terminated, lost state, and been restored. An application can set this value by using a counter that is incremented each time a service is restarted. The restart time of the service is expressed as seconds elapsed since 12:00 a.m. January 1, 1970.
/s:Envelope/s:Header/d:AppSequence/@SequenceId
This setting identifies a sequence within the context of an instance identifier. If it is omitted, the implied value is the null sequence. The value in this setting must be unique within ./@InstanceId.
/s:Envelope/s:Header/d:AppSequence/@MessageNumber
This setting identifies a message within the context of a sequence identifier and an instance identifier. must be incremented by a value of at least 1 for each message sent. Retransmission of this message at the transport level must maintain this value.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows Vista [desktop apps only] |
| Minimum supported server | Windows Server 2008 [desktop apps only] |
| Header | wsdtypes.h (include Wsdapi.h) |