_WSAOVERLAPPED structure

The WSAOVERLAPPED structure provides a communication medium between the initiation of an overlapped I/O operation and its subsequent completion. The WSAOVERLAPPED structure is compatible with the Windows OVERLAPPED structure.

Syntax

typedef struct _WSAOVERLAPPED {
  DWORD    Internal;
  DWORD    InternalHigh;
  DWORD    Offset;
  DWORD    OffsetHigh;
  WSAEVENT hEvent;
} WSAOVERLAPPED, *LPWSAOVERLAPPED;

Members

Internal

Type: ULONG_PTR

Reserved for internal use. The Internal member is used internally by the entity that implements overlapped I/O. For service providers that create sockets as installable file system (IFS) handles, this parameter is used by the underlying operating system. Other service providers (non-IFS providers) are free to use this parameter as necessary.

InternalHigh

Type: ULONG_PTR

Reserved. Used internally by the entity that implements overlapped I/O. For service providers that create sockets as IFS handles, this parameter is used by the underlying operating system. NonIFS providers are free to use this parameter as necessary.

Offset

Type: DWORD

Reserved for use by service providers.

OffsetHigh

Type: DWORD

Reserved for use by service providers.

hEvent

Type: HANDLE

If an overlapped I/O operation is issued without an I/O completion routine (the operation's lpCompletionRoutine parameter is set to null), then this parameter should either contain a valid handle to a WSAEVENT object or be null. If the lpCompletionRoutine parameter of the call is non-null then applications are free to use this parameter as necessary.

Requirements

   
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Header winsock2.h

See Also

WSACleanup

WSACloseEvent

WSACreateEvent

WSAGetOverlappedResult

WSARecv

WSASend

WSASendTo

WSASocket

WSAStartup

bind

closesocket