NAPI_PROVIDER_INSTALLATION_BLOB structure (nsemail.h)
The NAPI_PROVIDER_INSTALLATION_BLOB structure contains the information required to install a namespace provider for the NS_EMAIL namespace.
Syntax
typedef struct napi_provider_installation_blob_tag {
DWORD dwVersion;
DWORD dwProviderType;
DWORD fSupportsWildCard;
ULONG cDomains;
ULONG OffsetFirstDomain;
} NAPI_PROVIDER_INSTALLATION_BLOB;
Members
dwVersion
Type: DWORD
The version number of the NS_EMAIL namespace provider. This member is specific to the namespace provider.
dwProviderType
Type: DWORD
The type of namespace provider for the NS_EMAIL namespace. This member can be one of the values from the NAPI_PROVIDER_TYPE enumeration type defined in the Nsemail.h header file.
fSupportsWildCard
Type: DWORD
A Boolean value that indicates if this NS_EMAIL namespace provider supports wildcard names. If this member is nonzero, then an NS_EMAIL provider claims to be potentially able to resolve or register any name that does not belong to any domains the provider is specifically registered for as primary or secondary. If this member is nonzero, then the NS_EMAIL provider may be called to resolve or register any address, if no primary or secondary provider for the domain is available.
There may be multiple providers that claim to be able to resolve any address (the fSupportsWildCard set to nonzero). If there are namespace providers with this value that also registered as a wildcard provider, the providers are called in the order that they appear in the Winsock namespace catalog.
cDomains
Type: DWORD
The number of NAPI_DOMAIN_DESCRIPTION_BLOB structures the starting at the OffsetFirstDomain member used to describe domains that are supported by this NS_EMAIL namespace provider.
OffsetFirstDomain
Type: DWORD
The offset, in bytes, to the first of multiple NAPI_DOMAIN_DESCRIPTION_BLOB structures used to describe domains that are supported by this NS_EMAIL namespace provider. This offset must be aligned on a minimum of a four-byte boundary.
Remarks
This structure is supported on Windows Vista and later.
The NAPI_PROVIDER_INSTALLATION_BLOB structure contains the information required to install a namespace provider for the NS_EMAIL namespace. There may be multiple namespace providers for the NS_EMAIL namespace install on a local system.
Each namespace provider registered in the NS_EMAIL namespace can support multiple domains. As a result, there may be multiple NAPI_DOMAIN_DESCRIPTION_BLOB structures in the NAPI_PROVIDER_INSTALLATION_BLOB structure for an NS_EMAIL namespace provider. The list of supported domains is specified in the provider registration blob as a list of NAPI_DOMAIN_DESCRIPTION_BLOB structures. Each supported domain specification contains a NAPI_PROVIDER_LEVEL value in the AuthLevel member of the NAPI_DOMAIN_DESCRIPTION_BLOB that describes the level of authority provided by the provider for that domain.
Namespace providers are called in the following order to resolve or register an address in a domain. If a namespace provider registered as the primary provider for the domain, then this primary provider is called first. There are two cases depending on whether authoritative results are requested in the namespace query. The default for a query is to request authoritative results.
When authoritative results are requested in the query, then namespace providers are called as follows. If the primary provider is unavailable or is unable to resolve or register the address, then the first secondary provider in the Winsock catalog is called. If the secondary provider is unavailable or is unable to resolve or register the address, then the next secondary provider in the Winsock catalog is called. If all of the secondary providers are unavailable or are unable to resolve or register the address, then the first wildcard provider in the Winsock catalog is called. If the first wildcard provider is unavailable or is unable to resolve or register the address, then the next wildcard provider in the Winsock catalog is called.
When non-authoritative results are requested in the query, then namespace providers are called as follows. The primary provider, all secondary providers, and all wildcard providers are called and results from all of the queries are returned. The primary provider is called first. Secondary providers are called next, based on the order in the Winsock catalog. Wildcard providers are called next, based on the order in the Winsock catalog. The results that are returned are based on the order of the queries.
The WSCInstallNameSpaceEx and WSCInstallNameSpaceEx32 functions are used to install a namespace provider for the NS_EMAIL namespace using a NAPI_PROVIDER_INSTALLATION_BLOB structure.
The WSAEnumNameSpaceProvidersEx and WSCEnumNameSpaceProvidersEx32 functions are used to enumerate all namespace providers (including NS_EMAIL namespace providers) and to retrieve the NAPI_PROVIDER_INSTALLATION_BLOB structure for a provider if the provider registered a blob upon installation.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows Vista [desktop apps only] |
| Minimum supported server | Windows Server 2008 [desktop apps only] |
| Header | nsemail.h |