> For the complete documentation index, see [llms.txt](https://sandbox-docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://sandbox-docs.verifone.com/s-adk-5.1-programmers-guide/readme/modules/group__vfiipc/namespacevfiipc.md). # vfiipc [Data Structures](#nested-classes) | [Typedefs](#typedef-members) | [Enumerations](#enum-members) | [Functions](#func-members) | | | | --------------- | ------------------------------------------------------------------------------------------------------------------ | | Data Structures | | | class | [IPC](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_i_p_c.md) | | class | [JSObject](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_j_s_object.md) | | class | [Pipe](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_pipe.md) | | class | [TCP](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_t_c_p.md) | | class | [TLS](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_t_l_s.md) | | | | | --------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Typedefs | | | typedef void(\* | [ipcCallback](#ad81e4165dd387a02aacdb8a57c4fdd4f)) (void \*data, [IPC](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_i_p_c.md) \*ipc) | | typedef void(\* | [NotifyCallback](#ab377f9e2a200c707731b1984626d70c9)) (void \*data, const std::string \&from, const std::string \&to, const std::string \¬ification\_id, const [vfiipc::JSObject](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_j_s_object.md) \¶m, unsigned flags) | | typedef void(\* | [NotifyObserver](#a74917bd8d91bec1ff98234834e531071)) (void \*data, const std::string \&from, const std::string \&to, const std::string \¬ification\_id, unsigned flags) | | | | | ------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Enumerations | | | enum |

NotifyResult {
NOTIFY\_OK =0, NOTIFY\_ERR\_SERVER =-1, NOTIFY\_ERR\_APP\_ID =-2, NOTIFY\_ERR\_PERMISSION =-3,
NOTIFY\_ERR\_CONFIG\_FILE =-4, NOTIFY\_ERR\_CONFIG\_SYNTAX =-5
}

| | | | | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Functions | | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) void | [ipcSetAppID](#a88455cb389891217791604f188ac0fa5) (const std::string \&app\_id) | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) std::string | [ipcGetAppID](#a80d9206c7e76f24c2e2176308dbc3e06) () | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcNotify](#a3ad101cda0c973d26791bd8f194d4b80) (const std::string \&to, const std::string \¬ification\_id, const [vfiipc::JSObject](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_j_s_object.md) \¶m, unsigned flags=0, const std::string \&from="") | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcRegisterNotificationCB](#a625ae82cd0bc99851ccb8a8ffdcaea1e) (const std::string \¬ification\_id, [NotifyCallback](#ab377f9e2a200c707731b1984626d70c9) cb, void \*data, int priority=0, const std::string \&to="") | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcUnregisterNotificationCB](#a3fd5ffbe7bd9aa056c2400bd0a01e142) (const std::string \¬ification\_id, [NotifyCallback](#ab377f9e2a200c707731b1984626d70c9) cb, void \*data=0, const std::string \&to="") | | [DEPRECATED](/s-adk-5.1-programmers-guide/readme/files/dir_16ebd1d2d73191fda1ea8e9cfc03e012/dir_8266e5c14dc74e90f33f07ca932afbf0/dir_b923322e571c7bbbdf8ca0235601f24c/dir_a4bd7de3367ab1637f06ad0eeada778b/dir_f7f8126e2ed8b92f6435c9f330cc6acf/libseccmd-comp_8h.md#ac1e8a42306d8e67cb94ca31c3956ee78) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcUnregisterNotificationCB](#a861c0397a3c9754cd574d97e62da4d62) (const std::string \¬ification\_id, const std::string \&to="") | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcRegisterUnicastError](#a16b6627aaac4d6edab93696292c8b7a6) ([NotifyCallback](#ab377f9e2a200c707731b1984626d70c9) cb, void \*data) | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcUnregisterUnicastError](#a1bcfa904cfacfc8687ddca2204b2f778) ([NotifyCallback](#ab377f9e2a200c707731b1984626d70c9) cb, void \*data) | | [DEPRECATED](/s-adk-5.1-programmers-guide/readme/files/dir_16ebd1d2d73191fda1ea8e9cfc03e012/dir_8266e5c14dc74e90f33f07ca932afbf0/dir_b923322e571c7bbbdf8ca0235601f24c/dir_a4bd7de3367ab1637f06ad0eeada778b/dir_f7f8126e2ed8b92f6435c9f330cc6acf/libseccmd-comp_8h.md#ac1e8a42306d8e67cb94ca31c3956ee78) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcUnregisterUnicastError](#a0c523049653bf25c7dfae093f75704c8) () | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcRegisterObserver](#a5cb6705e4d5e2d94225eac66c760e872) ([NotifyObserver](#a74917bd8d91bec1ff98234834e531071) cb, void \*data) | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcUnregisterObserver](#ab259b3fce42df166ecc267066af9b105) ([NotifyObserver](#a74917bd8d91bec1ff98234834e531071) cb, void \*data) | | [DEPRECATED](/s-adk-5.1-programmers-guide/readme/files/dir_16ebd1d2d73191fda1ea8e9cfc03e012/dir_8266e5c14dc74e90f33f07ca932afbf0/dir_b923322e571c7bbbdf8ca0235601f24c/dir_a4bd7de3367ab1637f06ad0eeada778b/dir_f7f8126e2ed8b92f6435c9f330cc6acf/libseccmd-comp_8h.md#ac1e8a42306d8e67cb94ca31c3956ee78) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcUnregisterObserver](#a6c2855f19aa443ef85c42b02d296268b) () | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcNotificationServer](#a1862bc6c0fe6d07d60c677292cbc9619) () | | [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum [NotifyResult](#a7eda24f6e23d0f36491cc949c16ac4c3) | [ipcNotificationServer](#a7b8f16e995dfe57edad4cd97676a2eae) (const char \*config\_file) | ### DetailedDescription [IPC](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_i_p_c.md) namespace ### TypedefDocumentation ### ipcCallback typedef void(\\\* ipcCallback) (void \\\*data, [IPC](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_i_p_c.md) \\\*ipc) ### NotifyCallback typedef void(\\\* NotifyCallback) (void \\\*data, const std::string \&from, const std::string \&to, const std::string ¬ification\_id, const [vfiipc::JSObject](https://github.com/verifoneone/verifone-git-book-adk/tree/ADK5.1_staging/classvfiipc_1_1_j_s_object.md) ¶m, unsigned flags) Notify callback. The callback gets invoked when a matching notification has been sent. **Parameters** \[in] **data** opaque data pointer that was passed by the application when registering the callback. \[in] **from** source application ID \[in] **to** destination application ID that was used to send the notification. This may be used to distinguish the different cases send to application, send to single, send to all. \[in] **notification\_id** notification ID \[in] **param** parameters to send along the notification \[in] **flags** optional flags for future extensions {% hint style="info" %} All notification and error callbacks are run in separate threads. These are started on demand and terminate when the callback terminates. {% endhint %} ### NotifyObserver typedef void(\\\* NotifyObserver) (void \\\*data, const std::string \&from, const std::string \&to, const std::string ¬ification\_id, unsigned flags) Observer callback, will be called for all delivered notifications. If no receiver has been found the callback is called with an empty *to* parameter. **Parameters** \[in] **data** opaque data pointer that was passed by the application when registering the callback. \[in] **from** source application ID \[in] **to** resolved destination application ID \[in] **notification\_id** notification ID \[in] **flags** optional flags for future extensions {% hint style="info" %} All observer callbacks are run in separate threads. These are started on demand and terminate when the callback terminates. {% endhint %} ### EnumerationType Documentation ### NotifyResult enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) Notify result code | | | | --------------------------- | ------------------------------------------------------------------ | | Enumerator | | | NOTIFY\_OK | No error. | | NOTIFY\_ERR\_SERVER | notification server is not running | | NOTIFY\_ERR\_APP\_ID | the application ID has not been set yet, use ipcSetAppID to set it | | NOTIFY\_ERR\_PERMISSION | No permission to create the notification pipe | | NOTIFY\_ERR\_CONFIG\_FILE | The configuration file could not be opened for reading | | NOTIFY\_ERR\_CONFIG\_SYNTAX | The configuration file contained invalid input | ### FunctionDocumentation ### ipcGetAppID() [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) std::string vfiipc::ipcGetAppID read application ID that has been set using ipcSetAppID #### Returns application ID ### ipcNotificationServer()\[1/2] [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcNotificationServer start the notification server. Only one notification server may exist in the system. Normally it is started from the multi application controller. #### Returns error code {% hint style="info" %} This function only returns in case of error. {% endhint %} ### ipcNotificationServer()\[2/2] [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcNotificationServer start the notification server. Only one notification server may exist in the system. Normally it is started from the multi application controller. The config\_file names a configuration file that contains a whitelist of notifications that may be received from external IP addresses and that may be sent to external ones. **Parameters** \[in] **config\_file** name of the configuration file. May be NULL in which case it is identical to ipcNotificationServer(). #### Returns error code {% hint style="info" %} This function only returns in case of error. {% endhint %} {% hint style="info" %} If there is a configuration, then the notification server binds to IPADDR\_ANY so that notifications from external IP addresses may be accepted depending on the configuration. If config\_file is NULL or the configuration is empty, then the notification server binds to localhost so that only connects from localhost are supported. {% endhint %} {% hint style="info" %} On Verix connecting from external IP addresses is not supported, *config\_file* is ignored. {% endhint %} ### ipcNotify() [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcNotify Send notification **Parameters** \[in] **to** destination application ID or '1' to send notifications to exactly one receiver or '\*' to broadcast to all registered receivers \[in] **notification\_id** notification ID \[in] **param** parameters to send along the notification \[in] **flags** optional flags for future extensions \[in] **from** optional source application ID. If empty the application ID set by ipcSetAppID is used. This parameter is only required if a process needs to impersonate as another application, e.g. the multi app controller may use it to send notifications on behalf of CP apps #### Returns error code #### Examples [mac\_demo2.cpp](/s-adk-5.1-programmers-guide/readme/examples/mac_demo2_8cpp-example.md#a12), and [pm-demo.cpp](/s-adk-5.1-programmers-guide/readme/examples/pm-demo_8cpp-example.md#a58). ### ipcRegisterNotificationCB() [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcRegisterNotificationCB Register notification callback. New registrations will overwrite old ones for the same notification ID and destination app ID. **Parameters** \[in] **notification\_id** notification ID \[in] **cb** notification callback to be invoked. If NULL the registration will be discarded \[in] **data** opaque data pointer passed on to the callback \[in] **priority** priority of the callback. If several matching callbacks are found and the notification is not sent as a broadcast, then only the callback with the highest priority (highest value) will be called. \[in] **to** optional destination application ID. If empty then the application ID set by ipcSetAppID is used. This parameter is only required if a process needs to impersonate as another application, e.g. the multi app controller may use it to receive notifications on behalf of CP apps #### Returns error code #### Examples [mac\_demo1.cpp](/s-adk-5.1-programmers-guide/readme/examples/mac_demo1_8cpp-example.md#a15), [mac\_demo2.cpp](/s-adk-5.1-programmers-guide/readme/examples/mac_demo2_8cpp-example.md#a9), and [mac\_demo3.cpp](/s-adk-5.1-programmers-guide/readme/examples/mac_demo3_8cpp-example.md#a5). ### ipcRegisterObserver() [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcRegisterObserver register notification observer callback. The callback will be invoked for each notification delivered. **Parameters** \[in] **cb** notification callback to be invoked. \[in] **data** opaque data pointer passed on to the callback #### Returns error code ### ipcRegisterUnicastError() [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcRegisterUnicastError Register error callback. The error callback is invoked if the notification server cannot deliver a unicast notification to any receiver. Broadcast notifications are not considered. **Parameters** \[in] **cb** notification callback to be invoked. \[in] **data** opaque data pointer passed on to the callback #### Returns error code {% hint style="info" %} In case a receiver process terminates there is some risk that the failure to deliver a notification will go unnoticed: If the process terminates after receiving a notification but before sending an error, this error cannot be detected. {% endhint %} ### ipcSetAppID() [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) void vfiipc::ipcSetAppID application ID that will be used as source address when sending notifications **Parameters** \[in] **app\_id** application ID, the app ID should match the application ID used in the manifest. #### Examples [mac\_demo1.cpp](/s-adk-5.1-programmers-guide/readme/examples/mac_demo1_8cpp-example.md#a6), [mac\_demo2.cpp](/s-adk-5.1-programmers-guide/readme/examples/mac_demo2_8cpp-example.md#a6), [mac\_demo3.cpp](/s-adk-5.1-programmers-guide/readme/examples/mac_demo3_8cpp-example.md#a4), and [pm-demo.cpp](/s-adk-5.1-programmers-guide/readme/examples/pm-demo_8cpp-example.md#a10). ### ipcUnregisterNotificationCB()\[1/2] [DEPRECATED](/s-adk-5.1-programmers-guide/readme/files/dir_16ebd1d2d73191fda1ea8e9cfc03e012/dir_8266e5c14dc74e90f33f07ca932afbf0/dir_b923322e571c7bbbdf8ca0235601f24c/dir_a4bd7de3367ab1637f06ad0eeada778b/dir_f7f8126e2ed8b92f6435c9f330cc6acf/libseccmd-comp_8h.md#ac1e8a42306d8e67cb94ca31c3956ee78) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcUnregisterNotificationCB inline unregister a notification callback, shortcut for ipcRegisterNotificationCB(notification\_id,0,0,0,to); **Parameters** \[in] **notification\_id** notification ID \[in] **to** optional destination application ID. If null then the application ID set by ipcSetAppID is used. This parameter is only required if a process needs to impersonate as another application, e.g. the multi app controller may use it to receive notifications on behalf of CP apps #### Returns error code {% hint style="info" %} ipcUnregisterNotificationCB cannot be used within a callback to remove the callback itself: A deadlock occurs since it waits for the callback to terminate before removing it. {% endhint %} ### ipcUnregisterNotificationCB()\[2/2] [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcUnregisterNotificationCB unregister a notification callback. When the function returns, it is guaranteed, that the callback has terminated and will not be invoked any longer. **Parameters** \[in] **notification\_id** notification ID, must match the value passed to ipcRegisterNotificationCB \[in] **cb** notification callback used during registration. If NULL all callbacks registered for the notification ID are discarded. Use with care to not unintentionally discard registrations of other threads or libraries. \[in] **data** opaque data pointer used during registration. If NULL only cb is checked for finding the matching callback function. \[in] **to** optional destination application ID. If empty then the application ID set by ipcSetAppID is used, must match the value passed to ipcRegisterNotificationCB. #### Returns error code {% hint style="info" %} ipcUnregisterNotificationCB cannot be used within a callback to remove the callback itself: A deadlock occurs since it waits for the callback to terminate before removing it. {% endhint %} ### ipcUnregisterObserver()\[1/2] [DEPRECATED](/s-adk-5.1-programmers-guide/readme/files/dir_16ebd1d2d73191fda1ea8e9cfc03e012/dir_8266e5c14dc74e90f33f07ca932afbf0/dir_b923322e571c7bbbdf8ca0235601f24c/dir_a4bd7de3367ab1637f06ad0eeada778b/dir_f7f8126e2ed8b92f6435c9f330cc6acf/libseccmd-comp_8h.md#ac1e8a42306d8e67cb94ca31c3956ee78) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcUnregisterObserver inline unregister notification observer callback. When the function returns, it is guaranteed, that the callback has terminated and will not be invoked any longer. #### Returns error code {% hint style="info" %} ipcUnregisterObserver cannot be used within a callback to remove the callback itself: A deadlock occurs since it waits for the callback to terminate before removing it. {% endhint %} ### ipcUnregisterObserver()\[2/2] [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcUnregisterObserver unregister notification observer callback. When the function returns, it is guaranteed, that the callback has terminated and will not be invoked any longer. **Parameters** \[in] **cb** notification callback used during registration. If NULL all registrations will be discarded \[in] **data** opaque data pointer passed used during registration. If NULL only cb is checked for finding the matching callback function. #### Returns error code {% hint style="info" %} ipcUnregisterObserver cannot be used within a callback to remove the callback itself: A deadlock occurs since it waits for the callback to terminate before removing it. {% endhint %} ### ipcUnregisterUnicastError()\[1/2] [DEPRECATED](/s-adk-5.1-programmers-guide/readme/files/dir_16ebd1d2d73191fda1ea8e9cfc03e012/dir_8266e5c14dc74e90f33f07ca932afbf0/dir_b923322e571c7bbbdf8ca0235601f24c/dir_a4bd7de3367ab1637f06ad0eeada778b/dir_f7f8126e2ed8b92f6435c9f330cc6acf/libseccmd-comp_8h.md#ac1e8a42306d8e67cb94ca31c3956ee78) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcUnregisterUnicastError inline unregister an error callback, shortcut for ipcRegisterUnicastError(0,0); #### Returns error code {% hint style="info" %} ipcUnregisterUnicastError cannot be used within a callback to remove the callback itself: A deadlock occurs since it waits for the callback to terminate before removing it. {% endhint %} ### ipcUnregisterUnicastError()\[2/2] [DllSpec](/s-adk-5.1-programmers-guide/readme/files/dir_15b7eb99384c20f55db7776b7b1ecdad/dir_7d99a5752ef00d9a9478541a793df8d8/dir_b95d7ee73b2963b5e37f0a7269e7a4c6/sound_8h.md#ad7c2e1cb200073ed64c64285a5f37231) enum \[NotifyResult]\(#a7eda24f6e23d0f36491cc949c16ac4c3) vfiipc::ipcUnregisterUnicastError Unregister error callback. When the function returns, it is guaranteed, that the callback has terminated and will not be invoked any longer. **Parameters** \[in] **cb** notification callback used during registration. If NULL all callbacks registered for the notification ID are discarded. Use with care to not unintentionally discard registrations of other threads or libraries. \[in] **data** opaque data pointer used during registration. If NULL only cb is checked for finding the matching callback function. #### Returns error code {% hint style="info" %} In case a receiver process terminates there is some risk that the failure to deliver a notification will go unnoticed: If the process terminates after receiving a notification but before sending an error, this error cannot be detected. {% endhint %} {% hint style="info" %} ipcUnregisterUnicastError cannot be used within a callback to remove the callback itself: A deadlock occurs since it waits for the callback to terminate before removing it. {% endhint %} --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. 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