RpcServerInqCallAttributesA function (rpcasync.h)

The RpcServerInqCallAttributes function is an RPC server call that obtains client security context attributes.


RPC_STATUS RpcServerInqCallAttributesA(
  [in]      RPC_BINDING_HANDLE ClientBinding,
  [in, out] void               *RpcCallAttributes


[in] ClientBinding

Optional. For explicit binding within a server routine, ClientBinding is the binding handle with which the manager routine was called. See Remarks.

[in, out] RpcCallAttributes

RPC_CALL_ATTRIBUTES_V2 structure that receives call attributes.

Return value

Returns RPC_S_OK upon success, and RpcCallAttributes is filled. If ERROR_MORE_DATA is returned, one or more fields in RpcCallAttributes was of insufficient length and could not be filled. See Remarks in RPC_CALL_ATTRIBUTES_V2 for details on handling ERROR_MORE_DATA.

Upon failure, the contents of RpcCallAttributes is undefined and may be partially modified by RPC.

Note  For a list of valid error codes, see RPC Return Values.


The RpcServerInqCallAttributes function uses a versioning scheme to incorporate new capabilities without having to introduce new functions with suffix identifiers. For example, a second version of the RPC_CALL_ATTRIBUTES_V2, identified with a simple #define in the header, can add new members to facilitate new functionality built into future versions of the RpcServerInqCallAttributes function, without having to release a function called RpcServerInqCallAttributesEx.

If the RpcServerInqCallAttributes function is called outside a server routine, and if the function call queries the security context attributes for an asynchronous RPC call, ClientBinding can be retrieved by calling the RpcAsyncGetCallHandle function from the asynchronous handle.

The RpcServerInqCallAttributes function is not supported for datagram protocol sequences, such as ncadg_*. If invoked on a call that executes on a datagram protocol sequence, RPC_S_CANNOT_SUPPORT is returned.

The RpcServerInqCallAttributes function is thread-safe.


RPC_CALL_ATTRIBUTES CallAttributes;  // this maps to RPC_CALL_ATTRIBUTES_V1

memset(&CallAttributes, 0, sizeof(CallAttributes));
CallAttributes.Version = RPC_CALL_ATTRIBUTES_VERSION;    // maps to 1
CallAttributes.Flags = ;//....
Status = RpcServerInqCallAttributes(0, &ClientContextAttributes);


The rpcasync.h header defines RpcServerInqCallAttributes as an alias which 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 not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.


Minimum supported client Windows XP [desktop apps only]
Minimum supported server Windows Server 2003 [desktop apps only]
Target Platform Windows
Header rpcasync.h (include Rpc.h)
Library Rpcrt4.lib
DLL Rpcrt4.dll

See also