IOControlCode Enum

Definition

Namespace:

System.Net.Sockets

Assembly:

System.Net.Sockets.dll

Specifies the IO control codes supported by the IOControl(Int32, Byte[], Byte[]) method.

public enum class IOControlCode

public enum IOControlCode

type IOControlCode = 

Public Enum IOControlCode

Inheritance

Object

ValueType

Enum

IOControlCode

Fields

Name	Value	Description
EnableCircularQueuing	671088642	Replace the oldest queued datagram with an incoming datagram when the incoming message queues are full. This value is equal to the Winsock 2 SIO_ENABLE_CIRCULAR_QUEUEING constant.
Flush	671088644	Discard the contents of the sending queue. This value is equal to the Winsock 2 SIO_FLUSH constant.
AddressListChange	671088663	Enable receiving notification when the list of local interfaces for the socket's protocol family changes. This value is equal to the Winsock 2 SIO_ADDRESS_LIST_CHANGE constant.
DataToRead	1074030207	Return the number of bytes available for reading. This value is equal to the Winsock 2 FIONREAD constant.
OobDataRead	1074033415	Return information about out-of-band data waiting to be received. When using this control code on stream sockets, the return value indicates the number of bytes available.
GetBroadcastAddress	1207959557	Return a SOCKADDR structure that contains the broadcast address for the address family of the current socket. The returned address can be used with the SendTo method. This value is equal to the Winsock 2 SIO_GET_BROADCAST_ADDRESS constant. This value can be used on User Datagram Protocol (UDP) sockets only.
AddressListQuery	1207959574	Return the list of local interfaces that the socket can bind to. This value is equal to the Winsock 2 SIO_ADDRESS_LIST_QUERY constant.
QueryTargetPnpHandle	1207959576	Retrieve the underlying provider's SOCKET handle. This handle can be used to receive plug-and-play event notification. This value is equal to the Winsock 2 SIO_QUERY_TARGET_PNP_HANDLE constant.
AsyncIO	2147772029	Enable notification for when data is waiting to be received. This value is equal to the Winsock 2 FIOASYNC constant.
NonBlockingIO	2147772030	Control the blocking behavior of the socket. If the argument specified with this control code is zero, the socket is placed in blocking mode. If the argument is nonzero, the socket is placed in nonblocking mode. This value is equal to the Winsock 2 FIONBIO constant.
AssociateHandle	2281701377	Associate this socket with the specified handle of a companion interface. Refer to the appropriate protocol-specific annex in the Winsock 2 reference or documentation for the particular companion interface for additional details. It is recommended that the Component Object Model (COM) be used instead of this IOCTL to discover and track other interfaces that might be supported by a socket. This control code is present for backward compatibility with systems where COM is not available or cannot be used for some other reason. This value is equal to the Winsock 2 SIO_ASSOCIATE_HANDLE constant.
MultipointLoopback	2281701385	Control whether multicast data sent by the socket appears as incoming data in the sockets receive queue. This value is equal to the Winsock 2 SIO_MULTIPOINT_LOOPBACK constant.
MulticastScope	2281701386	Control the number of times a multicast packet can be forwarded by a router, also known as the Time to Live (TTL), or hop count. This value is equal to the Winsock 2 SIO_MULTICAST_SCOPE constant.
SetQos	2281701387	Set the Quality of Service (QOS) attributes for the socket. QOS defines the bandwidth requirements for the socket. This value is equal to the Winsock 2 SIO_SET_QOS constant.
SetGroupQos	2281701388	Set the Quality of Service (QOS) attributes for the socket group. This value is reserved for future use and is equal to the Winsock 2 SIO_SET_GROUP_QOS constant.
RoutingInterfaceChange	2281701397	Enable receiving notification when the local interface used to access a remote endpoint changes. This value is equal to the Winsock 2 SIO_ROUTING_INTERFACE_CHANGE constant.
NamespaceChange	2281701401	Control whether the socket receives notification when a namespace query becomes invalid. This control code is supported on Windows XP and later operating systems. This value is equal to the Winsock 2 SIO_NSP_NOTIFY_CHANGE constant.
ReceiveAll	2550136833	Enable receiving all IPv4 packets on the network. The socket must have address family InterNetwork, the socket type must be Raw, and the protocol type must be IP. The current user must belong to the Administrators group on the local computer, and the socket must be bound to a specific port. This value is equal to the Winsock 2 SIO_RCVALL constant.
ReceiveAllMulticast	2550136834	Enable receiving all multicast IPv4 packets on the network. These are packets with destination addresses in the range 224.0.0.0 through 239.255.255.255. The socket must have address family InterNetwork, the socket type must be Raw, and the protocol type must be Udp. The current user must belong to the Administrators group on the local computer, and the socket must be bound to a specific port. This value is equal to the Winsock 2 SIO_RCVALL_MCAST constant.
ReceiveAllIgmpMulticast	2550136835	Enable receiving all Internet Group Management Protocol (IGMP) packets on the network. The socket must have address family InterNetwork, the socket type must be Raw, and the protocol type must be Igmp. The current user must belong to the Administrators group on the local computer, and the socket must be bound to a specific port. This value is equal to the Winsock 2 SIO_RCVALL_IGMPMCAST constant.
KeepAliveValues	2550136836	Control sending TCP keep-alive packets and the interval at which they are sent. For additional information, see RFC 1122 section 4.2.3.6. This value is equal to the Winsock 2 SIO_KEEPALIVE_VALS constant.
AbsorbRouterAlert	2550136837	This value is equal to the Winsock 2 SIO_ABSORB_RTRALERT constant.
UnicastInterface	2550136838	Set the interface used for outgoing unicast packets. This value is equal to the Winsock 2 SIO_UCAST_IF constant.
LimitBroadcasts	2550136839	This value is equal to the Winsock 2 SIO_LIMIT_BROADCASTS constant.
BindToInterface	2550136840	Bind the socket to a specified interface index. This value is equal to the Winsock 2 SIO_INDEX_BIND constant.
MulticastInterface	2550136841	Set the interface used for outgoing multicast packets. The interface is identified by its index. This value is equal to the Winsock 2 SIO_INDEX_MCASTIF constant.
AddMulticastGroupOnInterface	2550136842	Join a multicast group using an interface identified by its index. This value is equal to the Winsock 2 SIO_INDEX_ADD_MCAST constant.
DeleteMulticastGroupFromInterface	2550136843	Remove the socket from a multicast group. This value is equal to the Winsock 2 SIO_INDEX_ADD_MCAST constant.
GetExtensionFunctionPointer	3355443206	Obtain provider-specific functions that are not part of the Winsock specification. Functions are specified using their provider-assigned GUID. This value is equal to the Winsock 2 SIO_GET_EXTENSION_FUNCTION_POINTER constant.
GetQos	3355443207	Retrieve the QOS structure associated with the socket. This value is equal to the Winsock 2 SIO_GET_QOS constant.
GetGroupQos	3355443208	Return the Quality of Service (QOS) attributes for the socket group. This value is reserved for future use, and is equal to the Winsock 2 SIO_GET_GROUP_QOS constant.
TranslateHandle	3355443213	Return a handle for the socket that is valid in the context of a companion interface. This value is equal to the Winsock 2 SIO_TRANSLATE_HANDLE constant.
RoutingInterfaceQuery	3355443220	Return the interface addresses that can be used to connect to the specified remote address. This value is equal to the Winsock 2 SIO_ROUTING_INTERFACE_QUERY constant.
AddressListSort	3355443225	Sort the structure returned by the AddressListQuery field and add scope ID information for IPv6 addresses. This control code is supported on Windows XP and later operating systems. This value is equal to the Winsock 2 SIO_ADDRESS_LIST_SORT constant.

Examples

The following code example calls the IOControl(IOControlCode, Byte[], Byte[]) method with a DataToRead parameter value and compares the result with accessing the.Available property.

void DisplayPendingByteCount( Socket^ s )
{
   array<Byte>^ outValue = BitConverter::GetBytes( 0 );
   
   // Check how many bytes have been received.
   s->IOControl( IOControlCode::DataToRead, nullptr, outValue );

   UInt32 bytesAvailable = BitConverter::ToUInt32( outValue, 0 );
   Console::Write( "server has {0} bytes pending,",
      bytesAvailable );
   Console::WriteLine( "Available property says {1}.",
      s->Available );
   return;
}

static void DisplayPendingByteCount(Socket s)
{
    byte[] outValue = BitConverter.GetBytes(0);

    // Check how many bytes have been received.
    s.IOControl(IOControlCode.DataToRead, null, outValue);

    uint bytesAvailable = BitConverter.ToUInt32(outValue, 0);
    Console.Write("server has {0} bytes pending. ",
        bytesAvailable);
    Console.WriteLine("Available property says {1}.",
                     s.Available);

    return;
}

Remarks

The IOControlCode enumeration provides named values for specifying socket operational modes. These values are the control codes passed to the Windows Sockets 2 (Winsock 2) WSAIoctl function.