WSAProviderConfigChange function (winsock2.h)

Article
10/13/2021

The WSAProviderConfigChange function notifies the application when the provider configuration is changed.

Syntax

INT WSAAPI WSAProviderConfigChange(
  [in, out] LPHANDLE                           lpNotificationHandle,
  [in]      LPWSAOVERLAPPED                    lpOverlapped,
  [in]      LPWSAOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine
);

Parameters

[in, out] lpNotificationHandle

Pointer to notification handle. If the notification handle is set to NULL (the handle value not the pointer itself), this function returns a notification handle in the location pointed to by lpNotificationHandle.

[in] lpOverlapped

Pointer to a WSAOVERLAPPED structure.

[in] lpCompletionRoutine

Type: _In_opt_ LPWSAOVERLAPPED_COMPLETION_ROUTINE

Pointer to the completion routine called when the provider change notification is received.

Return value

If no error occurs the WSAProviderConfigChange returns 0. Otherwise, a value of SOCKET_ERROR is returned and a specific error code may be retrieved by calling WSAGetLastError. The error code WSA_IO_PENDING indicates that the overlapped operation has been successfully initiated and that completion (and thus change event) will be indicated at a later time.

Error code	Meaning
WSANOTINITIALISED	A successful WSAStartup call must occur before using this function.
WSAENETDOWN	The network subsystem has failed.
WSA_NOT_ENOUGH_MEMORY	Not enough free memory available to complete the operation.
WSA_INVALID_HANDLE	Value pointed by lpNotificationHandle parameter is not a valid notification handle.
WSAEOPNOTSUPP	Current operating system environment does not support provider installation or removal without restart.

Remarks

The WSAProviderConfigChange function notifies the application of provider (both transport and namespace) installation or removal in Windows operating environments that support such configuration change without requiring a restart. When called for the first time (lpNotificationHandle parameter points to NULL handle), this function completes immediately and returns notification handle in the location pointed by lpNotificationHandle that can be used in subsequent calls to receive notifications of provider installation and removal. The second and any subsequent calls only complete when provider information changes since the time the call was made It is expected (but not required) that the application uses overlapped I/O on second and subsequent calls to WSAProviderConfigChange, in which case the call will return immediately and application will be notified of provider configuration changes using the completion mechanism chosen through specified overlapped completion parameters.

Notification handle returned by WSAProviderConfigChange is like any regular operating system handle that should be closed (when no longer needed) using Windows CloseHandle call.

The following sequence of actions can be used to guarantee that application always has current protocol configuration information:

Call WSAProviderConfigChange
Call WSAEnumProtocols and/or WSAEnumNameSpaceProviders
Whenever WSAProviderConfigChange notifies application of provider configuration change (through blocking or overlapped I/O), the whole sequence of actions should be repeated.

Windows 8.1 and Windows Server 2012 R2: This function is supported for Windows Store apps on Windows 8.1, Windows Server 2012 R2, and later.

Requirements

Requirement	Value
Minimum supported client	Windows 8.1, Windows Vista [desktop apps \| UWP apps]
Minimum supported server	Windows Server 2003 [desktop apps \| UWP apps]
Target Platform	Windows
Header	winsock2.h
Library	Ws2_32.lib
DLL	Ws2_32.dll