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PNRP and WSALookupServiceNext

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PNRP uses the WSALookupServiceNext function to match queries specified in a previous call to WSALookupServiceBegin. The results of the WSALookupServiceNext function are determined by settings in the WSAQUERYSET structure passed in the initial WSALookupServiceBegin function call. This function is used to perform the following two functions:

  • Resolving a peer name to a list of addresses
  • Enumerating network clouds

By using WSANSPIoctl, the lookup service can be used asynchronously. For information about using the lookup service functions asynchronously, see PNRP and WSANSPIoctl.

The WSALookupServiceNext function blocks even if WSANSPIoctl is called. Before calling WSALookupServiceNext, an application must wait until it receives a notification—if blocking is an issue.

Resolving a Peer Name to a List of Addresses

When resolving a peer name to a list of addresses, the LPWSAQUERYSET structure returned in the lpqsResults parameter contains the following values:

dwSize

Returns the size of the structure.

lpszServiceInstanceName

Returns a peer name—if LUP_RETURN_NAME, LUP_RETURN_ALL, or NULL are specified.

lpServiceClassID

Returns SVCID_PNRPNAME.

lpVersion

Returns NULL.

lpszComment

Returns a comment—if LUP_RETURN_COMMENT, LUP_RETURN_ALL, or NULL are specified.

dwNameSpace

Returns NS_PNRPNAME.

lpNSProviderID

Returns NS_PROVIDER_PNRPNAME.

lpszContext

Returns the cloud name if LUP_RETURN_NAME, LUP_RETURN_ALL, or NULL are specified.

dwNumberOfProtocols

Returns zero (0).

lpszQueryString

Returns NULL.

dwNumberOfCsAddrs

Returns the number of entries in the CSADDR_INFO array if LUP_RETURN_ADDR, LUP_RETURN_ALL, or NULL are specified. This value and the information in lpcsaBuffer are the key bits of information returned in this structure.

lpcsaBuffer

Returns a pointer to an array of CSADDR_INFO structures if LUP_RETURN_ADDR, LUP_RETURN_ALL, or NULL are specified. This buffer and the value in dwNumberOfCsAddrs are the key information bits returned in this structure.

dwOutputFlags

Returns zero (0).

lpBlob

Returns NULL.

Enumerating Network Clouds

When enumerating clouds, the LPWSAQUERYSET structure returned in the lpqsResults parameter contains the following values:

dwSize

Returns the size of the structure.

lpszServiceInstanceName

Returns a cloud name—if LUP_RETURN_NAME, LUP_RETURN_ALL, or NULL are specified.

lpServiceClassID

Returns SVCID_PNRPCLOUD.

lpVersion

Returns NULL.

lpszComment

Returns NULL.

dwNameSpace

Returns NS_PNRPCLOUD.

lpNSProviderID

Returns NS_PROVIDER_PNRPCLOUD.

lpszContext

Returns NULL.

dwNumberOfProtocols

Returns zero (0).

lpszQueryString

Returns NULL.

dwNumberOfCsAddrs

Returns zero (0).

lpcsaBuffer

Returns NULL.

dwOutputFlags

Returns zero (0).

lpBlob

Returns a pointer to a BLOB structure that points to a PNRPCLOUDINFO structure—if LUP_RETURN_BLOB, LUP_RETURN_ALL, or NULL are specified.

PNRPCLOUDINFO Structure

When enumerating cloud names, the following values are returned in the PNRPCLOUDINFO structure:

dwSize

The size of this structure.

Cloud

The actual cloud value.

enCloudState

The current state of a cloud. PNRP_CLOUD_STATE specifies the valid values.

enCloudFlags

Indicates that a cloud name is valid on a network, or only valid on a current computer. PNRP_CLOUD_FLAGS specifies the valid values. Some cloud names are valid on any computer on the same network. Other cloud names are valid only on a current computer, and may be valid only for a period of time.

  • If enCloudFlags is set to PNRP_CLOUD_NAME_LOCAL, the name is only valid locally.
  • If enCloudFlags is not set, then the cloud name can be transferred to other computers.

PNRP and BLOB

PNRP and WSALookupServiceEnd

PNRP and WSANSPIoctl

PNRP and WSAQUERYSET

PNRPCLOUDINFO

PNRPINFO

PNRP NSP Error Codes

WSALookupServiceBegin