WSAQUERYSETA structure (winsock2.h)
The WSAQUERYSET structure provides relevant information about a given service, including service class ID, service name, applicable namespace identifier and protocol information, as well as a set of transport addresses at which the service listens.
Syntax
typedef struct _WSAQuerySetA {
DWORD dwSize;
LPSTR lpszServiceInstanceName;
LPGUID lpServiceClassId;
LPWSAVERSION lpVersion;
LPSTR lpszComment;
DWORD dwNameSpace;
LPGUID lpNSProviderId;
LPSTR lpszContext;
DWORD dwNumberOfProtocols;
LPAFPROTOCOLS lpafpProtocols;
LPSTR lpszQueryString;
DWORD dwNumberOfCsAddrs;
LPCSADDR_INFO lpcsaBuffer;
DWORD dwOutputFlags;
LPBLOB lpBlob;
} WSAQUERYSETA, *PWSAQUERYSETA, *LPWSAQUERYSETA;
Members
dwSize
Type: DWORD
The size, in bytes, of the WSAQUERYSET structure. This member is used as a versioning mechanism since the size of the WSAQUERYSET structure has changed on later versions of Windows.
lpszServiceInstanceName
Type: LPTSTR
A pointer to an optional NULL-terminated string that contains service name. The semantics for using wildcards within the string are not defined, but can be supported by certain namespace providers.
lpServiceClassId
Type: LPGUID
The GUID corresponding to the service class. This member is required to be set.
lpVersion
Type: LPWSAVERSION
A pointer to an optional desired version number of the namespace provider. This member provides version comparison semantics (that is, the version requested must match exactly, or version must be not less than the value supplied).
lpszComment
Type: LPTSTR
This member is ignored for queries.
dwNameSpace
Type: DWORD
A namespace identifier that determines which namespace providers are queried. Passing a specific namespace identifier will result in only namespace providers that support the specified namespace being queried. Specifying NS_ALL will result in all installed and active namespace providers being queried.
Options for the dwNameSpace member are listed in the Winsock2.h include file. Several new namespace providers are included with Windows Vista and later. Other namespace providers can be installed, so the following possible values are only those commonly available. Many other values are possible.
lpNSProviderId
Type: LPGUID
A pointer to an optional GUID of a specific namespace provider to query in the case where multiple namespace providers are registered under a single namespace such as NS_DNS. Passing the GUID for a specific namespace provider will result in only the specified namespace provider being queried. The WSAEnumNameSpaceProviders and WSAEnumNameSpaceProvidersEx functions can be called to retrieve the GUID for a namespace provider.
lpszContext
Type: LPTSTR
A pointer to an optional starting point of the query in a hierarchical namespace.
dwNumberOfProtocols
Type: DWORD
The size, in bytes, of the protocol constraint array. This member can be zero.
lpafpProtocols
Type: LPAFPROTOCOLS
A pointer to an optional array of AFPROTOCOLS structures. Only services that utilize these protocols will be returned.
lpszQueryString
Type: LPTSTR
A pointer to an optional NULL-terminated query string. Some namespaces, such as Whois++, support enriched SQL-like queries that are contained in a simple text string. This parameter is used to specify that string.
dwNumberOfCsAddrs
Type: DWORD
This member is ignored for queries.
lpcsaBuffer
Type: LPCSADDR_INFO
This member is ignored for queries.
dwOutputFlags
Type: DWORD
This member is ignored for queries.
lpBlob
Type: LPBLOB
An optional pointer to data that is used to query or set provider-specific namespace information. The format of this information is specific to the namespace provider.
Remarks
The WSAQUERYSET structure is used as part of the original namespace provider version 1 architecture available on Windows 95 and later. A newer version 2 of the namespace architecture is available on Windows Vista and later.
In most instances, applications interested in only a particular transport protocol should constrain their query by address family and protocol rather than by namespace. This would allow an application that needs to locate a TCP/IP service, for example, to have its query processed by all available namespaces such as the local hosts file, DNS, and NIS.
Note
The winsock2.h header defines WSAQUERYSET as an alias that automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that is not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Header | winsock2.h |
See also
Bluetooth and WSAQUERYSET for Device Inquiry
Bluetooth and WSAQUERYSET for Service Inquiry