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# samgr\_lite<a name="EN-US_TOPIC_0000001081604584"></a>
- [Introduction](#section11660541593)
- [Directory Structure](#section1464106163817)
- [Constraints](#section1718733212019)
- [Developing a Service](#section159991817144514)
- [Developing a Feature of a Service](#section11510542164514)
- [Developing an External API for Intra-Process Communication](#section1685211117463)
- [Invoking a Service in the Same Process](#section3690162916462)
- [Developing an External API for IPC](#section9220246194615)
- [Invoking a Service in Another Process](#section114372711475)
- [Developing a Client Proxy for Inter-Process Service Invocation](#section09341923114710)
- [Repositories Involved](#section10365113863719)
## Introduction<a name="section11660541593"></a>
Due to limited platform resources, a unified system ability \(SA\) framework is provided to harmonize differences of hardware architectures \(for example, RISC-V, Cortex-M, and Cortex-A\), resources, and running modes. Two types of hardware platforms \(M- and A-core\) are defined.
- M-core: hardware platforms with Cortex-M or equivalent processing capabilities. The system memory is generally less than 512 KB. There is only a lightweight file system that can be used in limited scenarios, or no file system at all. M-core platforms comply with the Cortex Microcontroller Software Interface Standard \(CMSIS\).
- A-core: hardware platforms with Cortex-A or equivalent processing capabilities. The system memory is greater than 512 KB. There is a comprehensive file system for storing a large amount of data. A-core platforms comply with the Portable Operating System Interface \(POSIX\) specifications.
This service-oriented SA framework enables you to develop services, features, and external APIs, and implement multi-service process sharing and service invoking for inter-process communication \(IPC\). Wherein:
- M core provides services, features, external APIs, and multi-service process sharing development.
- In addition to the capabilities provided by M-core, A-core provides capabilities such as IPC service invoking, permission control for IPC service invoking, and IPC service API development.
Service-oriented architecture
![](figures/en-us_image_0000001128146921.png)
- Provider: a service provider that provides capabilities \(external APIs\) for the system
- Consumer: a service consumer that invokes the features \(external APIs\) provided by the service
- Samgr: an agency that manages capabilities provided by providers and helps consumers discover providers' capabilities
Main objects of the SA framework:
![](figures/en-us_image_0000001081285004.png)
- SamgrLite: provides service registration and discovery.
- Service: implements lifecycle APIs of the service during service development.
- Feature: implements lifecycle APIs of the feature during feature development.
- IUnknown: implements external APIs for services or features based on **IUnknown**.
- IClientProxy: implements the consumer's proxy to send messages during IPC invoking.
- IServerProxy: implements the provider's proxy during IPC invoking, which needs to be implemented by developers.
## Directory Structure<a name="section1464106163817"></a>
**Table 1** Structure of the source code directory of the SA framework
<a name="table2977131081412"></a>
<table><thead align="left"><tr id="row7977610131417"><th class="cellrowborder" valign="top" width="31.3%" id="mcps1.2.3.1.1"><p id="p18792459121314"><a name="p18792459121314"></a><a name="p18792459121314"></a>Directory</p>
</th>
<th class="cellrowborder" valign="top" width="68.7%" id="mcps1.2.3.1.2"><p id="p77921459191317"><a name="p77921459191317"></a><a name="p77921459191317"></a>Description</p>
</th>
</tr>
</thead>
<tbody><tr id="row17977171010144"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p2793159171311"><a name="p2793159171311"></a><a name="p2793159171311"></a>interfaces/kits/samgr_lite/samgr</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p879375920132"><a name="p879375920132"></a><a name="p879375920132"></a>External APIs of the M- and A-core SA frameworks</p>
</td>
</tr>
<tr id="row6978161091412"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p37931659101311"><a name="p37931659101311"></a><a name="p37931659101311"></a>interfaces/kits/samgr_lite/registry</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p6793059171318"><a name="p6793059171318"></a><a name="p6793059171318"></a>External APIs for service invocation between A-core processes</p>
</td>
</tr>
<tr id="row6978201031415"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p117935599130"><a name="p117935599130"></a><a name="p117935599130"></a>interfaces/kits/samgr_lite/communication/broadcast</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p0793185971316"><a name="p0793185971316"></a><a name="p0793185971316"></a>External APIs of the event broadcast service within M- and A-core processes</p>
</td>
</tr>
<tr id="row124243183397"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p104249183396"><a name="p104249183396"></a><a name="p104249183396"></a>services/samgr_lite/samgr/adapter</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p2424318203914"><a name="p2424318203914"></a><a name="p2424318203914"></a>POSIX and CMSIS interface adaptation layer, which is used to harmonize the differences between the APIs of M- and A-core</p>
</td>
</tr>
<tr id="row1634915717405"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p193493571406"><a name="p193493571406"></a><a name="p193493571406"></a>services/samgr_lite/samgr/registry</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p14349257184012"><a name="p14349257184012"></a><a name="p14349257184012"></a>Stub functions for M-core service registration and discovery</p>
</td>
</tr>
<tr id="row1385432741312"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p1485582714135"><a name="p1485582714135"></a><a name="p1485582714135"></a>services/samgr_lite/samgr/source</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p085522751319"><a name="p085522751319"></a><a name="p085522751319"></a>Basic code for the M- and A-core SA frameworks</p>
</td>
</tr>
<tr id="row7968155877"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p89681851717"><a name="p89681851717"></a><a name="p89681851717"></a>services/samgr_lite/samgr_client</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p169681051873"><a name="p169681051873"></a><a name="p169681051873"></a>Registration and discovery for service invocation between A-core processes</p>
</td>
</tr>
<tr id="row18291912179"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p1729111214715"><a name="p1729111214715"></a><a name="p1729111214715"></a>services/samgr_lite/samgr_server</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p7839893352"><a name="p7839893352"></a><a name="p7839893352"></a>IPC address management and access control for service invocation between A-core processes</p>
</td>
</tr>
<tr id="row6971514279"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p1797118141671"><a name="p1797118141671"></a><a name="p1797118141671"></a>services/samgr_lite/samgr_endpoint</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p597119145716"><a name="p597119145716"></a><a name="p597119145716"></a>Packet RX/TX management for A-core IPC</p>
</td>
</tr>
<tr id="row33121991272"><td class="cellrowborder" valign="top" width="31.3%" headers="mcps1.2.3.1.1 "><p id="p143121991875"><a name="p143121991875"></a><a name="p143121991875"></a>services/samgr_lite/communication/broadcast</p>
</td>
<td class="cellrowborder" valign="top" width="68.7%" headers="mcps1.2.3.1.2 "><p id="p16312169179"><a name="p16312169179"></a><a name="p16312169179"></a>Event broadcast service for M- and A-core processes</p>
</td>
</tr>
</tbody>
</table>
## Constraints<a name="section1718733212019"></a>
- The SA framework is developed using the C programming language.
- Services in the same process use **IUnknown** for invoking. Messages are passed to the service through **IUnknown**.
- The service name and feature name must be constant character strings and the length must be less than 16 bytes.
- More-core depends on the Bootstrap service and calls the **OHOS\_SystemInit\(\)** function in the system startup function.
- A-core depends on the Samgr library and calls the **SAMGR\_Bootstrap\(\)** function in the **main** function.
## Developing a Service<a name="section159991817144514"></a>
- Inherit and redefine a service.
```
typedef struct ExampleService {
INHERIT_SERVICE;
INHERIT_IUNKNOWNENTRY(DefaultFeatureApi);
Identity identity;
} ExampleService;
```
- Implement the lifecycle function of the service.
```
static const char *GetName(Service *service)
{
return EXAMPLE_SERVICE;
}
static BOOL Initialize(Service *service, Identity identity)
{
ExampleService *example = (ExampleService *)service;
// Save the unique ID of the service, which is used when IUnknown is used to send messages to the service.
example->identity = identity;
return TRUE;
}
static BOOL MessageHandle(Service *service, Request *msg)
{
ExampleService *example = (ExampleService *)service;
switch (msg->msgId) {
case MSG_SYNC:
// Process the service.
break;
default:break;
}
return FALSE;
}
static TaskConfig GetTaskConfig(Service *service)
{
TaskConfig config = {LEVEL_HIGH, PRI_BELOW_NORMAL,
0x800, 20, SHARED_TASK};
return config;
}
```
- Create a service object.
```
static ExampleService g_example = {
.GetName = GetName,
.Initialize = Initialize,
.MessageHandle = MessageHandle,
.GetTaskConfig = GetTaskConfig,
SERVER_IPROXY_IMPL_BEGIN,
.Invoke = NULL,
.SyncCall = SyncCall,
IPROXY_END,
};
```
- Register the service and API with Samgr.
```
static void Init(void)
{
SAMGR_GetInstance()->RegisterService((Service *)&g_example);
SAMGR_GetInstance()->RegisterDefaultFeatureApi(EXAMPLE_SERVICE, GET_IUNKNOWN(g_example));
}
```
- Define the initializer of the service.
```
SYSEX_SERVICE_INIT(Init);
```
## Developing a Feature of a Service<a name="section11510542164514"></a>
- Inherit and redefine a feature.
```
typedef struct DemoFeature {
INHERIT_FEATURE;
INHERIT_IUNKNOWNENTRY(DemoApi);
Identity identity;
Service *parent;
} DemoFeature;
```
- Implement the lifecycle function of the feature.
```
static const char *FEATURE_GetName(Feature *feature)
{
return EXAMPLE_FEATURE;
}
static void FEATURE_OnInitialize(Feature *feature, Service *parent, Identity identity)
{
DemoFeature *demoFeature = (DemoFeature *)feature;
demoFeature->identity = identity;
demoFeature->parent = parent;
}
static void FEATURE_OnStop(Feature *feature, Identity identity)
{
g_example.identity.queueId = NULL;
g_example.identity.featureId = -1;
g_example.identity.serviceId = -1;
}
static BOOL FEATURE_OnMessage(Feature *feature, Request *request)
{
if (request->msgId == MSG_PROC) {
Response response = {.data = "Yes, you did!", .len = 0};
SAMGR_SendResponse(request, &response);
return TRUE;
} else {
if (request->msgId == MSG_TIME_PROC) {
LOS_Msleep(WAIT_FEATURE_PROC * 10);
if (request->msgValue) {
SAMGR_PrintServices();
} else {
SAMGR_PrintOperations();
}
AsyncTimeCall(GET_IUNKNOWN(g_example));
return FALSE;
}
}
return FALSE;
}
```
- Create a feature object.
```
static DemoFeature g_example = {
.GetName = FEATURE_GetName,
.OnInitialize = FEATURE_OnInitialize,
.OnStop = FEATURE_OnStop,
.OnMessage = FEATURE_OnMessage,
DEFAULT_IUNKNOWN_ENTRY_BEGIN,
.AsyncCall = AsyncCall,
.AsyncTimeCall = AsyncTimeCall,
.SyncCall = SyncCall,
.AsyncCallBack = AsyncCallBack,
DEFAULT_IUNKNOWN_ENTRY_END,
.identity = {-1, -1, NULL},
};
```
- Register the feature and API with Samgr.
```
static void Init(void){
SAMGR_GetInstance()->RegisterFeature(EXAMPLE_SERVICE, (Feature *)&g_example);
SAMGR_GetInstance()->RegisterFeatureApi(EXAMPLE_SERVICE, EXAMPLE_FEATURE, GET_IUNKNOWN(g_example));
}
```
- Define the initializer of the feature.
```
SYSEX_FEATURE_INIT(Init);
```
## Developing an External API for Intra-Process Communication<a name="section1685211117463"></a>
- Define the **IUnknown** API.
```
typedef struct DemoApi {
INHERIT_IUNKNOWN;
BOOL (*AsyncCall)(IUnknown *iUnknown, const char *buff);
BOOL (*AsyncTimeCall)(IUnknown *iUnknown);
BOOL (*SyncCall)(IUnknown *iUnknown, struct Payload *payload);
BOOL (*AsyncCallBack)(IUnknown *iUnknown, const char *buff, Handler handler);
} DemoApi;
```
- Define the reference object of **IUnknown**.
```
typedef struct DemoRefApi {
INHERIT_IUNKNOWNENTRY(DemoApi);
} DemoRefApi;
```
- Initialize the object of **IUnknown**.
```
static DemoRefApi api = {
DEFAULT_IUNKNOWN_ENTRY_BEGIN,
.AsyncCall = AsyncCall,
.AsyncTimeCall = AsyncTimeCall,
.SyncCall = SyncCall,
.AsyncCallBack = AsyncCallBack,
DEFAULT_IUNKNOWN_ENTRY_END,
};
```
- Register the feature API.
```
SAMGR_GetInstance()->RegisterFeatureApi(EXAMPLE_SERVICE, EXAMPLE_FEATURE, GET_IUNKNOWN(api));
```
## Invoking a Service in the Same Process<a name="section3690162916462"></a>
- Obtain the external API of the service.
```
DemoApi *demoApi = NULL;
IUnknown *iUnknown = SAMGR_GetInstance()->GetFeatureApi(EXAMPLE_SERVICE, EXAMPLE_FEATURE);
if (iUnknown == NULL) {
return NULL;
}
int result = iUnknown->QueryInterface(iUnknown, DEFAULT_VERSION, (void **)&demoApi);
if (result != 0 || demoApi == NULL) {
return NULL;
}
```
- Call the API.
```
if (demoApi->AsyncCallBack == NULL) {
return NULL;
}
demoApi->AsyncCallBack((IUnknown *)demoApi, "I wanna async call callback good result!", AsyncHandler);
```
- Release the API.
```
int32 ref = demoApi->Release((IUnknown *)demoApi);
```
## Developing an External API for IPC<a name="section9220246194615"></a>
- Inherit **IServerProxy** to replace **IUnknown**: INHERIT\_SERVER\_IPROXY
```
typedef struct DemoFeatureApi {
INHERIT_SERVER_IPROXY;
BOOL (*AsyncCall)(IUnknown *iUnknown, const char *buff);
BOOL (*AsyncTimeCall)(IUnknown *iUnknown);
BOOL (*SyncCall)(IUnknown *iUnknown, struct Payload *payload);
BOOL (*AsyncCallBack)(IUnknown *iUnknown, const char *buff, IOwner notify, INotifyFunc handler);
} DemoFeatureApi;
```
- Initialize the **IServerProxy** object.
```
static DemoFeature g_example = {
SERVER_IPROXY_IMPL_BEGIN,
.Invoke = Invoke,
.AsyncCall = AsyncCall,
.AsyncTimeCall = AsyncTimeCall,
.SyncCall = SyncCall,
.AsyncCallBack = AsyncCallBack,
IPROXY_END,
};
```
- Implement the **Invoke** function to process IPC messages.
```
static int32 Invoke(IServerProxy *iProxy, int funcId, void *origin, IpcIo *req, IpcIo *reply)
{
DemoFeatureApi *api = (DemoFeatureApi *)iProxy;
BOOL ret;
size_t len = 0;
switch (funcId) {
case ID_ASYNCALL:
ret = api->AsyncCall((IUnknown *)iProxy, (char *)IpcIoPopString(req, &len));
IpcIoPushBool(reply, ret);
break;
case ID_ASYNTIMECALL:
ret = api->AsyncTimeCall((IUnknown *)iProxy);
IpcIoPushBool(reply, ret);
break;
case ID_SYNCCALL: {
struct Payload payload;
payload.id = IpcIoPopInt32(req);
payload.value = IpcIoPopInt32(req);
payload.name = (char *)IpcIoPopString(req, &len);
ret = api->SyncCall((IUnknown *)iProxy, &payload);
IpcIoPushString(reply, ret ? "TRUE" : "FALSE");
}
break;
case ID_ASYNCCALLBACK: { // convert to sync proxy
IpcIoPushString(reply, "Yes, you did!");
IpcIoPushBool(reply, TRUE);
}
break;
default:
IpcIoPushBool(reply, FALSE);
break;
}
return EC_SUCCESS;
}
```
- Register the API. This step is same as the API registration for intra-process communication.
```
SAMGR_GetInstance()->RegisterFeatureApi(EXAMPLE_SERVICE, EXAMPLE_FEATURE, GET_IUNKNOWN(g_example));
```
## Invoking a Service in Another Process<a name="section114372711475"></a>
- Obtain the external API of the service in another process.
```
IClientProxy *demoApi = NULL;
IUnknown *iUnknown = SAMGR_GetInstance()->GetFeatureApi(EXAMPLE_SERVICE, EXAMPLE_FEATURE);
if (iUnknown == NULL) {
return NULL;
}
int result = iUnknown->QueryInterface(iUnknown, CLIENT_PROXY_VER, (void **)&demoApi);
if (result != 0 || demoApi == NULL) {
return NULL;
}
```
- Invoke the API for sending IPC messages.
```
IpcIo request;char data[250];
IpcIoInit(&request, data, sizeof(data), 0);
demoApi->Invoke(demoApi, 0, &request, NULL, NULL);
```
- Release the API.
```
int32 ref = demoApi->Release((IUnknown *)demoApi);
```
## Developing a Client Proxy for Inter-Process Service Invocation<a name="section09341923114710"></a>
- Define a client proxy for the IPC API.
```
typedef struct DemoClientProxy {
INHERIT_CLIENT_IPROXY;
BOOL (*AsyncCall)(IUnknown *iUnknown, const char *buff);
BOOL (*AsyncTimeCall)(IUnknown *iUnknown);
BOOL (*SyncCall)(IUnknown *iUnknown, struct Payload *payload);
BOOL (*AsyncCallBack)(IUnknown *iUnknown, const char *buff, IOwner notify, INotifyFunc handler);
} DemoClientProxy;
typedef struct DemoClientEntry {
INHERIT_IUNKNOWNENTRY(DemoClientProxy);
} DemoClientEntry;
```
- Enable the client proxy to encapsulate the IPC message API.
```
static BOOL AsyncCall(IUnknown *iUnknown, const char *buff)
{
DemoClientProxy *proxy = (DemoClientProxy *)iUnknown;
IpcIo request;
char data[MAX_DATA_LEN];
IpcIoInit(&request, data, MAX_DATA_LEN, 0);
IpcIoPushString(&request, buff);
int ret = proxy->Invoke((IClientProxy *)proxy, ID_ASYNCALL, &request, NULL, NULL);
return ret == EC_SUCCESS;
}
static BOOL AsyncTimeCall(IUnknown *iUnknown)
{
DemoClientProxy *proxy = (DemoClientProxy *)iUnknown;
IpcIo request;
char data[MAX_DATA_LEN];
IpcIoInit(&request, data, MAX_DATA_LEN, 0);
int ret = proxy->Invoke((IClientProxy *)proxy, ID_ASYNTIMECALL, &request, NULL, NULL);
return ret == EC_SUCCESS;
}
static int Callback(IOwner owner, int code, IpcIo *reply)
{
size_t len = 0;
return strcpy_s(owner, MAX_DATA_LEN, (char *)IpcIoPopString(reply, &len));
}
static BOOL SyncCall(IUnknown *iUnknown, struct Payload *payload)
{
DemoClientProxy *proxy = (DemoClientProxy *)iUnknown;
IpcIo request;
char data[MAX_DATA_LEN];
IpcIoInit(&request, data, MAX_DATA_LEN, 0);
IpcIoPushInt32(&request, payload->id);
IpcIoPushInt32(&request, payload->value);
IpcIoPushString(&request, payload->name);
int ret = proxy->Invoke((IClientProxy *)proxy, ID_SYNCCALL, &request, data, Callback);
data[MAX_DATA_LEN - 1] = 0;
HILOG_INFO(HILOG_MODULE_APP, "[TID:0x%lx]Remote response is %s!", pthread_self(), data);
return ret == EC_SUCCESS;
}
struct CurrentNotify {
IOwner notify;
INotifyFunc handler;
};
static int CurrentCallback(IOwner owner, int code, IpcIo *reply)
{
struct CurrentNotify *notify = (struct CurrentNotify *)owner;
size_t len = 0;
char *response = (char *)IpcIoPopString(reply, &len);
HILOG_INFO(HILOG_MODULE_APP, "[TID:0x%lx]Notify Remote response is %s!", pthread_self(), response);
notify->handler(notify->notify, response);
return EC_SUCCESS;
}
static BOOL AsyncCallBack(IUnknown *iUnknown, const char *buff, IOwner notify, INotifyFunc handler)
{
struct CurrentNotify owner = {notify, handler};
DemoClientProxy *proxy = (DemoClientProxy *)iUnknown;
IpcIo request;
char data[MAX_DATA_LEN];
IpcIoInit(&request, data, MAX_DATA_LEN, 0);
IpcIoPushString(&request, buff);
int ret = proxy->Invoke((IClientProxy *)proxy, ID_ASYNCCALLBACK, &request, &owner, CurrentCallback);
return ret == EC_SUCCESS;
}
```
- Implement the factory method for creating the client proxy.
```
void *DEMO_CreatClient(const char *service, const char *feature, uint32 size)
{
(void)service;
(void)feature;
uint32 len = size + sizeof(DemoClientEntry);
uint8 *client = malloc(len);
(void)memset_s(client, len, 0, len);
DemoClientEntry *entry = (DemoClientEntry *)&client[size];
entry->ver = ((uint16)CLIENT_PROXY_VER | (uint16)DEFAULT_VERSION);
entry->ref = 1;
entry->iUnknown.QueryInterface = IUNKNOWN_QueryInterface;
entry->iUnknown.AddRef = IUNKNOWN_AddRef;
entry->iUnknown.Release = IUNKNOWN_Release;
entry->iUnknown.Invoke = NULL;
entry->iUnknown.AsyncCall = AsyncCall;
entry->iUnknown.AsyncTimeCall = AsyncTimeCall;
entry->iUnknown.SyncCall = SyncCall;
entry->iUnknown.AsyncCallBack = AsyncCallBack;
return client;
}
void DEMO_DestroyClient(const char *service, const char *feature, void *iproxy)
{
free(iproxy);
}
```
- Register the factory method of the client proxy with Samgr.
```
SAMGR_RegisterFactory(EXAMPLE_SERVICE, EXAMPLE_FEATURE, DEMO_CreatClient, DEMO_DestroyClient);
```
- Obtain the external API of the service in another process.
```
DemoClientProxy *demoApi = NULL;
IUnknown *iUnknown = SAMGR_GetInstance()->GetFeatureApi(EXAMPLE_SERVICE, EXAMPLE_FEATURE);
if (iUnknown == NULL) {
return NULL;
}
int result = iUnknown->QueryInterface(iUnknown, DEFAULT_VERSION, (void **)&demoApi);
if (result != 0 || demoApi == NULL) {
return NULL;
}
```
- Invoke the client proxy API of the service in another process.
```
if (demoApi->AsyncCallBack == NULL) {
return NULL;
}
demoApi->AsyncCallBack((IUnknown *)demoApi,
"I wanna async call callback good result!", NULL, AsyncHandler);
```
- Release the API.
```
int32 ref = demoApi->Release((IUnknown *)demoApi);
```
## Repositories Involved<a name="section10365113863719"></a>
[Distributed Scheduler subsystem](en-us_topic_0000001115719369.md)
**[samgr\_lite](https://gitee.com/openharmony/distributedschedule_services_samgr_lite)**
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