Highlevel Client Functionality

The following definitions are convenience functions making use of the standard OPC UA services in the background. This is a less flexible way of handling the stack, because at many places sensible defaults are presumed; at the same time using these functions is the easiest way of implementing an OPC UA application, as you will not have to consider all the details that go into the OPC UA services. If more flexibility is needed, you can always achieve the same functionality using the raw OPC UA services.

Read Attributes

The following functions can be used to retrieve a single node attribute. Use the regular service to read several attributes at once.

/* Don't call this function, use the typed versions */
UA_StatusCode
__UA_Client_readAttribute(UA_Client *client, const UA_NodeId *nodeId,
                          UA_AttributeId attributeId, void *out,
                          const UA_DataType *outDataType);

static UA_INLINE UA_StatusCode
UA_Client_readNodeIdAttribute(UA_Client *client, const UA_NodeId nodeId,
                              UA_NodeId *outNodeId) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_NODEID,
                                     outNodeId, &UA_TYPES[UA_TYPES_NODEID]);
}

static UA_INLINE UA_StatusCode
UA_Client_readNodeClassAttribute(UA_Client *client, const UA_NodeId nodeId,
                                 UA_NodeClass *outNodeClass) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_NODECLASS,
                                     outNodeClass, &UA_TYPES[UA_TYPES_NODECLASS]);
}

static UA_INLINE UA_StatusCode
UA_Client_readBrowseNameAttribute(UA_Client *client, const UA_NodeId nodeId,
                                  UA_QualifiedName *outBrowseName) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_BROWSENAME,
                                     outBrowseName,
                                     &UA_TYPES[UA_TYPES_QUALIFIEDNAME]);
}

static UA_INLINE UA_StatusCode
UA_Client_readDisplayNameAttribute(UA_Client *client, const UA_NodeId nodeId,
                                   UA_LocalizedText *outDisplayName) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_DISPLAYNAME,
                                     outDisplayName,
                                     &UA_TYPES[UA_TYPES_LOCALIZEDTEXT]);
}

static UA_INLINE UA_StatusCode
UA_Client_readDescriptionAttribute(UA_Client *client, const UA_NodeId nodeId,
                                   UA_LocalizedText *outDescription) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_DESCRIPTION,
                                     outDescription,
                                     &UA_TYPES[UA_TYPES_LOCALIZEDTEXT]);
}

static UA_INLINE UA_StatusCode
UA_Client_readWriteMaskAttribute(UA_Client *client, const UA_NodeId nodeId,
                                 UA_UInt32 *outWriteMask) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_WRITEMASK,
                                     outWriteMask, &UA_TYPES[UA_TYPES_UINT32]);
}

static UA_INLINE UA_StatusCode
UA_Client_readUserWriteMaskAttribute(UA_Client *client, const UA_NodeId nodeId,
                                     UA_UInt32 *outUserWriteMask) {
    return __UA_Client_readAttribute(client, &nodeId,
                                     UA_ATTRIBUTEID_USERWRITEMASK,
                                     outUserWriteMask,
                                     &UA_TYPES[UA_TYPES_UINT32]);
}

static UA_INLINE UA_StatusCode
UA_Client_readIsAbstractAttribute(UA_Client *client, const UA_NodeId nodeId,
                                  UA_Boolean *outIsAbstract) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_ISABSTRACT,
                                     outIsAbstract, &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_readSymmetricAttribute(UA_Client *client, const UA_NodeId nodeId,
                                 UA_Boolean *outSymmetric) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_SYMMETRIC,
                                     outSymmetric, &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_readInverseNameAttribute(UA_Client *client, const UA_NodeId nodeId,
                                   UA_LocalizedText *outInverseName) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_INVERSENAME,
                                     outInverseName,
                                     &UA_TYPES[UA_TYPES_LOCALIZEDTEXT]);
}

static UA_INLINE UA_StatusCode
UA_Client_readContainsNoLoopsAttribute(UA_Client *client, const UA_NodeId nodeId,
                                       UA_Boolean *outContainsNoLoops) {
    return __UA_Client_readAttribute(client, &nodeId,
                                     UA_ATTRIBUTEID_CONTAINSNOLOOPS,
                                     outContainsNoLoops,
                                     &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_readEventNotifierAttribute(UA_Client *client, const UA_NodeId nodeId,
                                     UA_Byte *outEventNotifier) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_EVENTNOTIFIER,
                                     outEventNotifier, &UA_TYPES[UA_TYPES_BYTE]);
}

static UA_INLINE UA_StatusCode
UA_Client_readValueAttribute(UA_Client *client, const UA_NodeId nodeId,
                             UA_Variant *outValue) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_VALUE,
                                     outValue, &UA_TYPES[UA_TYPES_VARIANT]);
}

static UA_INLINE UA_StatusCode
UA_Client_readDataTypeAttribute(UA_Client *client, const UA_NodeId nodeId,
                                UA_NodeId *outDataType) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_DATATYPE,
                                     outDataType, &UA_TYPES[UA_TYPES_NODEID]);
}

static UA_INLINE UA_StatusCode
UA_Client_readValueRankAttribute(UA_Client *client, const UA_NodeId nodeId,
                                 UA_Int32 *outValueRank) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_VALUERANK,
                                     outValueRank, &UA_TYPES[UA_TYPES_INT32]);
}

UA_StatusCode
UA_Client_readArrayDimensionsAttribute(UA_Client *client, const UA_NodeId nodeId,
                                       UA_UInt32 **outArrayDimensions,
                                       size_t *outArrayDimensionsSize);

static UA_INLINE UA_StatusCode
UA_Client_readAccessLevelAttribute(UA_Client *client, const UA_NodeId nodeId,
                                   UA_Byte *outAccessLevel) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_ACCESSLEVEL,
                                     outAccessLevel, &UA_TYPES[UA_TYPES_BYTE]);
}

static UA_INLINE UA_StatusCode
UA_Client_readUserAccessLevelAttribute(UA_Client *client, const UA_NodeId nodeId,
                                       UA_Byte *outUserAccessLevel) {
    return __UA_Client_readAttribute(client, &nodeId,
                                     UA_ATTRIBUTEID_USERACCESSLEVEL,
                                     outUserAccessLevel,
                                     &UA_TYPES[UA_TYPES_BYTE]);
}

static UA_INLINE UA_StatusCode
UA_Client_readMinimumSamplingIntervalAttribute(UA_Client *client,
                                               const UA_NodeId nodeId,
                                               UA_Double *outMinSamplingInterval) {
    return __UA_Client_readAttribute(client, &nodeId,
                                     UA_ATTRIBUTEID_MINIMUMSAMPLINGINTERVAL,
                                     outMinSamplingInterval,
                                     &UA_TYPES[UA_TYPES_DOUBLE]);
}

static UA_INLINE UA_StatusCode
UA_Client_readHistorizingAttribute(UA_Client *client, const UA_NodeId nodeId,
                                   UA_Boolean *outHistorizing) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_HISTORIZING,
                                     outHistorizing, &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_readExecutableAttribute(UA_Client *client, const UA_NodeId nodeId,
                                  UA_Boolean *outExecutable) {
    return __UA_Client_readAttribute(client, &nodeId, UA_ATTRIBUTEID_EXECUTABLE,
                                     outExecutable, &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_readUserExecutableAttribute(UA_Client *client, const UA_NodeId nodeId,
                                      UA_Boolean *outUserExecutable) {
    return __UA_Client_readAttribute(client, &nodeId,
                                     UA_ATTRIBUTEID_USEREXECUTABLE,
                                     outUserExecutable,
                                     &UA_TYPES[UA_TYPES_BOOLEAN]);
}

Write Attributes

The following functions can be use to write a single node attribute at a time. Use the regular write service to write several attributes at once.

/* Don't call this function, use the typed versions */
UA_StatusCode
__UA_Client_writeAttribute(UA_Client *client, const UA_NodeId *nodeId,
                           UA_AttributeId attributeId, const void *in,
                           const UA_DataType *inDataType);

static UA_INLINE UA_StatusCode
UA_Client_writeNodeIdAttribute(UA_Client *client, const UA_NodeId nodeId,
                               const UA_NodeId *newNodeId) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_NODEID,
                                      newNodeId, &UA_TYPES[UA_TYPES_NODEID]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeNodeClassAttribute(UA_Client *client, const UA_NodeId nodeId,
                                  const UA_NodeClass *newNodeClass) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_NODECLASS,
                                      newNodeClass, &UA_TYPES[UA_TYPES_NODECLASS]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeBrowseNameAttribute(UA_Client *client, const UA_NodeId nodeId,
                                   const UA_QualifiedName *newBrowseName) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_BROWSENAME,
                                      newBrowseName,
                                      &UA_TYPES[UA_TYPES_QUALIFIEDNAME]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeDisplayNameAttribute(UA_Client *client, const UA_NodeId nodeId,
                                    const UA_LocalizedText *newDisplayName) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_DISPLAYNAME,
                                      newDisplayName,
                                      &UA_TYPES[UA_TYPES_LOCALIZEDTEXT]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeDescriptionAttribute(UA_Client *client, const UA_NodeId nodeId,
                                    const UA_LocalizedText *newDescription) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_DESCRIPTION,
                                      newDescription,
                                      &UA_TYPES[UA_TYPES_LOCALIZEDTEXT]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeWriteMaskAttribute(UA_Client *client, const UA_NodeId nodeId,
                                  const UA_UInt32 *newWriteMask) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_WRITEMASK,
                                      newWriteMask, &UA_TYPES[UA_TYPES_UINT32]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeUserWriteMaskAttribute(UA_Client *client, const UA_NodeId nodeId,
                                      const UA_UInt32 *newUserWriteMask) {
    return __UA_Client_writeAttribute(client, &nodeId,
                                      UA_ATTRIBUTEID_USERWRITEMASK,
                                      newUserWriteMask,
                                      &UA_TYPES[UA_TYPES_UINT32]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeIsAbstractAttribute(UA_Client *client, const UA_NodeId nodeId,
                                   const UA_Boolean *newIsAbstract) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_ISABSTRACT,
                                      newIsAbstract, &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeSymmetricAttribute(UA_Client *client, const UA_NodeId nodeId,
                                  const UA_Boolean *newSymmetric) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_SYMMETRIC,
                                      newSymmetric, &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeInverseNameAttribute(UA_Client *client, const UA_NodeId nodeId,
                                    const UA_LocalizedText *newInverseName) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_INVERSENAME,
                                      newInverseName,
                                      &UA_TYPES[UA_TYPES_LOCALIZEDTEXT]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeContainsNoLoopsAttribute(UA_Client *client, const UA_NodeId nodeId,
                                        const UA_Boolean *newContainsNoLoops) {
    return __UA_Client_writeAttribute(client, &nodeId,
                                      UA_ATTRIBUTEID_CONTAINSNOLOOPS,
                                      newContainsNoLoops,
                                      &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeEventNotifierAttribute(UA_Client *client, const UA_NodeId nodeId,
                                      const UA_Byte *newEventNotifier) {
    return __UA_Client_writeAttribute(client, &nodeId,
                                      UA_ATTRIBUTEID_EVENTNOTIFIER,
                                      newEventNotifier,
                                      &UA_TYPES[UA_TYPES_BYTE]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeValueAttribute(UA_Client *client, const UA_NodeId nodeId,
                              const UA_Variant *newValue) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_VALUE,
                                      newValue, &UA_TYPES[UA_TYPES_VARIANT]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeDataTypeAttribute(UA_Client *client, const UA_NodeId nodeId,
                                 const UA_NodeId *newDataType) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_DATATYPE,
                                      newDataType, &UA_TYPES[UA_TYPES_NODEID]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeValueRankAttribute(UA_Client *client, const UA_NodeId nodeId,
                                  const UA_Int32 *newValueRank) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_VALUERANK,
                                      newValueRank, &UA_TYPES[UA_TYPES_INT32]);
}

UA_StatusCode
UA_Client_writeArrayDimensionsAttribute(UA_Client *client, const UA_NodeId nodeId,
                                        const UA_UInt32 *newArrayDimensions,
                                        size_t newArrayDimensionsSize);

static UA_INLINE UA_StatusCode
UA_Client_writeAccessLevelAttribute(UA_Client *client, const UA_NodeId nodeId,
                                    const UA_Byte *newAccessLevel) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_ACCESSLEVEL,
                                      newAccessLevel, &UA_TYPES[UA_TYPES_BYTE]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeUserAccessLevelAttribute(UA_Client *client, const UA_NodeId nodeId,
                                        const UA_Byte *newUserAccessLevel) {
    return __UA_Client_writeAttribute(client, &nodeId,
                                      UA_ATTRIBUTEID_USERACCESSLEVEL,
                                      newUserAccessLevel,
                                      &UA_TYPES[UA_TYPES_BYTE]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeMinimumSamplingIntervalAttribute(UA_Client *client,
                                                const UA_NodeId nodeId,
                                                const UA_Double *newMinInterval) {
    return __UA_Client_writeAttribute(client, &nodeId,
                                      UA_ATTRIBUTEID_MINIMUMSAMPLINGINTERVAL,
                                      newMinInterval, &UA_TYPES[UA_TYPES_DOUBLE]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeHistorizingAttribute(UA_Client *client, const UA_NodeId nodeId,
                                    const UA_Boolean *newHistorizing) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_HISTORIZING,
                                      newHistorizing, &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeExecutableAttribute(UA_Client *client, const UA_NodeId nodeId,
                                   const UA_Boolean *newExecutable) {
    return __UA_Client_writeAttribute(client, &nodeId, UA_ATTRIBUTEID_EXECUTABLE,
                                      newExecutable, &UA_TYPES[UA_TYPES_BOOLEAN]);
}

static UA_INLINE UA_StatusCode
UA_Client_writeUserExecutableAttribute(UA_Client *client, const UA_NodeId nodeId,
                                       const UA_Boolean *newUserExecutable) {
    return __UA_Client_writeAttribute(client, &nodeId,
                                      UA_ATTRIBUTEID_USEREXECUTABLE,
                                      newUserExecutable,
                                      &UA_TYPES[UA_TYPES_BOOLEAN]);
}

Method Calling

UA_StatusCode
UA_Client_call(UA_Client *client, const UA_NodeId objectId,
               const UA_NodeId methodId, size_t inputSize, const UA_Variant *input,
               size_t *outputSize, UA_Variant **output);

Node Management

See the section on server-side node management.

UA_StatusCode
UA_Client_addReference(UA_Client *client, const UA_NodeId sourceNodeId,
                       const UA_NodeId referenceTypeId, UA_Boolean isForward,
                       const UA_String targetServerUri,
                       const UA_ExpandedNodeId targetNodeId,
                       UA_NodeClass targetNodeClass);

UA_StatusCode
UA_Client_deleteReference(UA_Client *client, const UA_NodeId sourceNodeId,
                          const UA_NodeId referenceTypeId, UA_Boolean isForward,
                          const UA_ExpandedNodeId targetNodeId,
                          UA_Boolean deleteBidirectional);

UA_StatusCode
UA_Client_deleteNode(UA_Client *client, const UA_NodeId nodeId,
                     UA_Boolean deleteTargetReferences);

/* Don't call this function, use the typed versions */
UA_StatusCode
__UA_Client_addNode(UA_Client *client, const UA_NodeClass nodeClass,
                    const UA_NodeId requestedNewNodeId,
                    const UA_NodeId parentNodeId,
                    const UA_NodeId referenceTypeId,
                    const UA_QualifiedName browseName,
                    const UA_NodeId typeDefinition, const UA_NodeAttributes *attr,
                    const UA_DataType *attributeType, UA_NodeId *outNewNodeId);

static UA_INLINE UA_StatusCode
UA_Client_addVariableNode(UA_Client *client, const UA_NodeId requestedNewNodeId,
                          const UA_NodeId parentNodeId,
                          const UA_NodeId referenceTypeId,
                          const UA_QualifiedName browseName,
                          const UA_NodeId typeDefinition,
                          const UA_VariableAttributes attr,
                          UA_NodeId *outNewNodeId) {
    return __UA_Client_addNode(client, UA_NODECLASS_VARIABLE, requestedNewNodeId,
                               parentNodeId, referenceTypeId, browseName,
                               typeDefinition, (const UA_NodeAttributes*)&attr,
                               &UA_TYPES[UA_TYPES_VARIABLEATTRIBUTES],
                               outNewNodeId);
}

static UA_INLINE UA_StatusCode
UA_Client_addVariableTypeNode(UA_Client *client,
                              const UA_NodeId requestedNewNodeId,
                              const UA_NodeId parentNodeId,
                              const UA_NodeId referenceTypeId,
                              const UA_QualifiedName browseName,
                              const UA_VariableTypeAttributes attr,
                              UA_NodeId *outNewNodeId) {
    return __UA_Client_addNode(client, UA_NODECLASS_VARIABLETYPE,
                               requestedNewNodeId,
                               parentNodeId, referenceTypeId, browseName,
                               UA_NODEID_NULL, (const UA_NodeAttributes*)&attr,
                               &UA_TYPES[UA_TYPES_VARIABLETYPEATTRIBUTES],
                               outNewNodeId);
}

static UA_INLINE UA_StatusCode
UA_Client_addObjectNode(UA_Client *client, const UA_NodeId requestedNewNodeId,
                        const UA_NodeId parentNodeId,
                        const UA_NodeId referenceTypeId,
                        const UA_QualifiedName browseName,
                        const UA_NodeId typeDefinition,
                        const UA_ObjectAttributes attr, UA_NodeId *outNewNodeId) {
    return __UA_Client_addNode(client, UA_NODECLASS_OBJECT, requestedNewNodeId,
                               parentNodeId, referenceTypeId, browseName,
                               typeDefinition, (const UA_NodeAttributes*)&attr,
                               &UA_TYPES[UA_TYPES_OBJECTATTRIBUTES], outNewNodeId);
}

static UA_INLINE UA_StatusCode
UA_Client_addObjectTypeNode(UA_Client *client, const UA_NodeId requestedNewNodeId,
                            const UA_NodeId parentNodeId,
                            const UA_NodeId referenceTypeId,
                            const UA_QualifiedName browseName,
                            const UA_ObjectTypeAttributes attr,
                            UA_NodeId *outNewNodeId) {
    return __UA_Client_addNode(client, UA_NODECLASS_OBJECTTYPE, requestedNewNodeId,
                               parentNodeId, referenceTypeId, browseName,
                               UA_NODEID_NULL, (const UA_NodeAttributes*)&attr,
                               &UA_TYPES[UA_TYPES_OBJECTTYPEATTRIBUTES],
                               outNewNodeId);
}

static UA_INLINE UA_StatusCode
UA_Client_addViewNode(UA_Client *client, const UA_NodeId requestedNewNodeId,
                      const UA_NodeId parentNodeId,
                      const UA_NodeId referenceTypeId,
                      const UA_QualifiedName browseName,
                      const UA_ViewAttributes attr,
                      UA_NodeId *outNewNodeId) {
    return __UA_Client_addNode(client, UA_NODECLASS_VIEW, requestedNewNodeId,
                               parentNodeId, referenceTypeId, browseName,
                               UA_NODEID_NULL, (const UA_NodeAttributes*)&attr,
                               &UA_TYPES[UA_TYPES_VIEWATTRIBUTES], outNewNodeId);
}

static UA_INLINE UA_StatusCode
UA_Client_addReferenceTypeNode(UA_Client *client,
                               const UA_NodeId requestedNewNodeId,
                               const UA_NodeId parentNodeId,
                               const UA_NodeId referenceTypeId,
                               const UA_QualifiedName browseName,
                               const UA_ReferenceTypeAttributes attr,
                               UA_NodeId *outNewNodeId) {
    return __UA_Client_addNode(client, UA_NODECLASS_REFERENCETYPE,
                               requestedNewNodeId,
                               parentNodeId, referenceTypeId, browseName,
                               UA_NODEID_NULL, (const UA_NodeAttributes*)&attr,
                               &UA_TYPES[UA_TYPES_REFERENCETYPEATTRIBUTES],
                               outNewNodeId);
}

static UA_INLINE UA_StatusCode
UA_Client_addDataTypeNode(UA_Client *client, const UA_NodeId requestedNewNodeId,
                          const UA_NodeId parentNodeId,
                          const UA_NodeId referenceTypeId,
                          const UA_QualifiedName browseName,
                          const UA_DataTypeAttributes attr,
                          UA_NodeId *outNewNodeId) {
    return __UA_Client_addNode(client, UA_NODECLASS_DATATYPE, requestedNewNodeId,
                               parentNodeId, referenceTypeId, browseName,
                               UA_NODEID_NULL, (const UA_NodeAttributes*)&attr,
                               &UA_TYPES[UA_TYPES_DATATYPEATTRIBUTES],
                               outNewNodeId);
}

static UA_INLINE UA_StatusCode
UA_Client_addMethodNode(UA_Client *client, const UA_NodeId requestedNewNodeId,
                        const UA_NodeId parentNodeId,
                        const UA_NodeId referenceTypeId,
                        const UA_QualifiedName browseName,
                        const UA_MethodAttributes attr,
                        UA_NodeId *outNewNodeId) {
    return __UA_Client_addNode(client, UA_NODECLASS_METHOD, requestedNewNodeId,
                               parentNodeId, referenceTypeId, browseName,
                               UA_NODEID_NULL, (const UA_NodeAttributes*)&attr,
                               &UA_TYPES[UA_TYPES_METHODATTRIBUTES], outNewNodeId);
}

Subscriptions Handling

At this time, the client does not yet contain its own thread or event-driven main-loop. So the client will not perform any actions automatically in the background. This is especially relevant for subscriptions. The user will have to periodically call UA_Client_Subscriptions_manuallySendPublishRequest. See also here.

#ifdef UA_ENABLE_SUBSCRIPTIONS

typedef struct {
    UA_Double requestedPublishingInterval;
    UA_UInt32 requestedLifetimeCount;
    UA_UInt32 requestedMaxKeepAliveCount;
    UA_UInt32 maxNotificationsPerPublish;
    UA_Boolean publishingEnabled;
    UA_Byte priority;
} UA_SubscriptionSettings;

extern const UA_SubscriptionSettings UA_SubscriptionSettings_standard;

UA_StatusCode
UA_Client_Subscriptions_new(UA_Client *client, UA_SubscriptionSettings settings,
                            UA_UInt32 *newSubscriptionId);

UA_StatusCode
UA_Client_Subscriptions_remove(UA_Client *client, UA_UInt32 subscriptionId);

UA_StatusCode
UA_Client_Subscriptions_manuallySendPublishRequest(UA_Client *client);

typedef void (*UA_MonitoredItemHandlingFunction)(UA_UInt32 monId,
                                                 UA_DataValue *value,
                                                 void *context);

UA_StatusCode
UA_Client_Subscriptions_addMonitoredItem(UA_Client *client,
                                         UA_UInt32 subscriptionId,
                                         UA_NodeId nodeId, UA_UInt32 attributeID,
                                         UA_MonitoredItemHandlingFunction hf,
                                         void *hfContext,
                                         UA_UInt32 *newMonitoredItemId);

UA_StatusCode
UA_Client_Subscriptions_removeMonitoredItem(UA_Client *client,
                                            UA_UInt32 subscriptionId,
                                            UA_UInt32 monitoredItemId);

#endif

Misc Highlevel Functionality

/* Get the namespace-index of a namespace-URI
 *
 * @param client The UA_Client struct for this connection
 * @param namespaceUri The interested namespace URI
 * @param namespaceIndex The namespace index of the URI. The value is unchanged
 *        in case of an error
 * @return Indicates whether the operation succeeded or returns an error code */
UA_StatusCode
UA_Client_NamespaceGetIndex(UA_Client *client, UA_String *namespaceUri,
                            UA_UInt16 *namespaceIndex);

#ifndef HAVE_NODEITER_CALLBACK
#define HAVE_NODEITER_CALLBACK
/* Iterate over all nodes referenced by parentNodeId by calling the callback
   function for each child node */
typedef UA_StatusCode (*UA_NodeIteratorCallback)(UA_NodeId childId,
                                                 UA_Boolean isInverse,
                                                 UA_NodeId referenceTypeId,
                                                 void *handle);
#endif

UA_StatusCode
UA_Client_forEachChildNodeCall(UA_Client *client, UA_NodeId parentNodeId,
                               UA_NodeIteratorCallback callback, void *handle) ;