FwpmProviderContextSubscribeChanges0 function (fwpmu.h)

The FwpmProviderContextSubscribeChanges0 function is used to request the delivery of notifications regarding changes in a particular provider context.

Syntax

DWORD FwpmProviderContextSubscribeChanges0(
  [in]           HANDLE                                    engineHandle,
  [in]           const FWPM_PROVIDER_CONTEXT_SUBSCRIPTION0 *subscription,
  [in]           FWPM_PROVIDER_CONTEXT_CHANGE_CALLBACK0    callback,
  [in, optional] void                                      *context,
  [out]          HANDLE                                    *changeHandle
);

Parameters

[in] engineHandle

Type: HANDLE

Handle for an open session to the filter engine. Call FwpmEngineOpen0 to open a session to the filter engine.

[in] subscription

Type: const FWPM_PROVIDER_CONTEXT_SUBSCRIPTION0*

The notifications to be delivered.

[in] callback

Type: FWPM_PROVIDER_CONTEXT_CHANGE_CALLBACK0

Function pointer that will be invoked when a notification is ready for delivery.

[in, optional] context

Type: void*

Optional context pointer. This pointer is passed to the callback function along with details of the change.

[out] changeHandle

Type: HANDLE*

Handle to the newly created subscription.

Return value

Type: DWORD

Remarks

Subscribers do not receive notifications for changes made with the same session handle used to subscribe. This is because subscribers only need to see changes made by others since they already know which changes they made themselves.

This function cannot be called from within a transaction. It will fail with FWP_E_TXN_IN_PROGRESS. See Object Management for more information about transactions.

The caller needs FWPM_ACTRL_SUBSCRIBE access to the provider context's container and FWPM_ACTRL_READ access to the provider context. The subscriber will only get notifications for provider contexts to which it has FWPM_ACTRL_READ access. See Access Control for more information.

FwpmProviderContextSubscribeChanges0 is a specific implementation of FwpmProviderContextSubscribeChanges. See WFP Version-Independent Names and Targeting Specific Versions of Windows for more information.

Requirements

See also

FWPM_PROVIDER_CONTEXT_CHANGE_CALLBACK0

FWPM_PROVIDER_CONTEXT_SUBSCRIPTION0