Socket.IOControl Method (Int32, Byte[], Byte[])
Assembly: System (in system.dll)
public: int IOControl ( int ioControlCode, array<unsigned char>^ optionInValue, array<unsigned char>^ optionOutValue )
public int IOControl ( int ioControlCode, byte[] optionInValue, byte[] optionOutValue )
public function IOControl ( ioControlCode : int, optionInValue : byte[], optionOutValue : byte[] ) : int
Not applicable.
Parameters
- ioControlCode
An Int32 value that specifies the control code of the operation to perform.
- optionInValue
A Byte array that contains the input data required by the operation.
- optionOutValue
A Byte array that contains the output data returned by the operation.
Return Value
The number of bytes in the optionOutValue parameter.| Exception type | Condition |
|---|---|
| An error occurred when attempting to access the socket. See the Remarks section for more information. | |
| The Socket has been closed. | |
| An attempt was made to change the blocking mode without using the Blocking property. | |
| A caller in the call stack does not have the required permissions. |
The IOControl method provides low-level access to the operating system Socket underlying the current instance of the Socket class. For more information, see the WSAIoctl documentation in the MSDN library.
Note: |
|---|
| If you receive a SocketException, use the SocketException.ErrorCode property to obtain the specific error code. After you have obtained this code, refer to the Windows Sockets version 2 API error code documentation in the MSDN library for a detailed description of the error. |
Note: |
|---|
| This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing. |
The following code example compares the results of FIONREAD and the Available property.
// FIONREAD is also available as the "Available" property. const int FIONREAD = 0x4004667F; void DisplayPendingByteCount( Socket^ s ) { array<Byte>^ outValue = BitConverter::GetBytes( 0 ); // Check how many bytes have been received. s->IOControl( FIONREAD, nullptr, outValue ); UInt32 bytesAvailable = BitConverter::ToUInt32( outValue, 0 ); Console::WriteLine( "server has {0} bytes pending. Available property says {1}.", bytesAvailable, s->Available ); return; }
// FIONREAD is also available as the "Available" property.
public static final int FIONREAD = 0x4004667F;
static void DisplayPendingByteCount(Socket s)
{
ubyte outValue[] = BitConverter.GetBytes(0);
// Check how many bytes have been received.
s.IOControl(FIONREAD, null, outValue);
UInt32 bytesAvailable = BitConverter.ToUInt32(outValue, 0);
//ToDo: Unsigned Integers not supported- converted to int
Console.WriteLine("server has {0} bytes pending. Available property "
+ "says {1}.", bytesAvailable.ToString(),
(System.Int32)s.get_Available());
return;
} //DisplayPendingByteCount
- SecurityPermission to execute unmanaged code. Associated enumeration: UnmanagedCode.
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.
Note: