C++/Java *Device::connect*(..), disconnect(): Return HCIStatusCode instead of just boolean, passing through potential HCI error detail

The HCIStatusCode on failed connect*/disconnect commands issued via direct_bt HCI,
could help applications making a better fail-recovery decision than just having the binary result.

18 files changed, 224 insertions, 141 deletions

diff --git a/api/direct_bt/DBTAdapter.hpp b/api/direct_bt/DBTAdapter.hpp
index 682c0e0b..62edb663 100644
--- a/api/direct_bt/DBTAdapter.hpp
+++ b/api/direct_bt/DBTAdapter.hpp
@@ -178,12 +178,12 @@ namespace direct_bt {
             friend std::shared_ptr<DBTDevice> DBTDevice::getSharedInstance() const;
             friend void DBTDevice::releaseSharedInstance() const;
             friend std::shared_ptr<ConnectionInfo> DBTDevice::getConnectionInfo();
-            friend bool DBTDevice::disconnect(const bool sentFromManager, const bool ioErrorCause,const HCIStatusCode reason);
+            friend HCIStatusCode DBTDevice::disconnect(const bool sentFromManager, const bool ioErrorCause,const HCIStatusCode reason);
             friend void DBTDevice::remove();
-            friend bool DBTDevice::connectLE(uint16_t interval, uint16_t window,
-                                             uint16_t min_interval, uint16_t max_interval,
-                                             uint16_t latency, uint16_t supervision_timeout);
-            friend bool DBTDevice::connectBREDR(const uint16_t pkt_type, const uint16_t clock_offset, const uint8_t role_switch);
+            friend HCIStatusCode DBTDevice::connectLE(uint16_t interval, uint16_t window,
+                                                      uint16_t min_interval, uint16_t max_interval,
+                                                      uint16_t latency, uint16_t supervision_timeout);
+            friend HCIStatusCode DBTDevice::connectBREDR(const uint16_t pkt_type, const uint16_t clock_offset, const uint8_t role_switch);
             friend std::vector<std::shared_ptr<GATTService>> DBTDevice::getGATTServices();
 
             bool addConnectedDevice(const std::shared_ptr<DBTDevice> & device);
diff --git a/api/direct_bt/DBTDevice.hpp b/api/direct_bt/DBTDevice.hpp
index f31af362..9ac2c6d7 100644
--- a/api/direct_bt/DBTDevice.hpp
+++ b/api/direct_bt/DBTDevice.hpp
@@ -92,8 +92,8 @@ namespace direct_bt {
             void notifyDisconnected();
             void notifyConnected(const uint16_t handle);
 
-            bool disconnect(const bool fromDisconnectCB, const bool ioErrorCause,
-                            const HCIStatusCode reason=HCIStatusCode::REMOTE_USER_TERMINATED_CONNECTION );
+            HCIStatusCode disconnect(const bool fromDisconnectCB, const bool ioErrorCause,
+                                     const HCIStatusCode reason=HCIStatusCode::REMOTE_USER_TERMINATED_CONNECTION );
 
         public:
             const uint64_t ts_creation;
@@ -211,14 +211,16 @@ namespace direct_bt {
             /**
              * Establish a HCI BDADDR_LE_PUBLIC or BDADDR_LE_RANDOM connection to this device.
              * <p>
-             * If this device's addressType is not BDADDR_LE_PUBLIC or BDADDR_LE_RANDOM, 0 is being returned.
+             * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.12 LE Create Connection command
              * </p>
              * <p>
-             * Returns true if the command has been accepted, otherwise false.
+             * If this device's addressType is not BDADDR_LE_PUBLIC or BDADDR_LE_RANDOM,
+             * HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM is being returned.
              * </p>
              * <p>
              * The actual new connection handle will be delivered asynchronous and
-             * the connection event can be caught via AdapterStatusListener::deviceConnected(..).
+             * the connection event can be caught via AdapterStatusListener::deviceConnected(..),
+             * or if failed via AdapterStatusListener::deviceDisconnected(..).
              * </p>
              * <p>
              * The device is tracked by the managing adapter.
@@ -231,57 +233,62 @@ namespace direct_bt {
              * Set window to the same value as the interval, enables continuous scanning.
              * </p>
              *
-             * @param peer_mac_type
-             * @param own_mac_type
              * @param le_scan_interval in units of 0.625ms, default value 48 for 30ms, min value 4 for 2.5ms -> 0x4000 for 10.24s
              * @param le_scan_window in units of 0.625ms, default value 48 for 30ms,  min value 4 for 2.5ms -> 0x4000 for 10.24s. Shall be <= le_scan_interval
              * @param conn_interval_min in units of 1.25ms, default value 15 for 19.75ms
              * @param conn_interval_max in units of 1.25ms, default value 15 for 19.75ms
              * @param conn_latency slave latency in units of connection events, default value 0
              * @param supervision_timeout in units of 10ms, default value 1000 for 10000ms or 10s.
-             * @return
+             * @return the HCIStatusCode result whether the command has been accepted, HCIStatusCode::SUCCESS on success.
+             * @return HCIStatusCode::SUCCESS if the command has been accepted, otherwise HCIStatusCode may disclose reason for rejection.
              */
-            bool connectLE(const uint16_t le_scan_interval=48, const uint16_t le_scan_window=48,
-                           const uint16_t conn_interval_min=0x000F, const uint16_t conn_interval_max=0x000F,
-                           const uint16_t conn_latency=0x0000, const uint16_t supervision_timeout=number(HCIConstInt::LE_CONN_TIMEOUT_MS)/10);
+            HCIStatusCode connectLE(const uint16_t le_scan_interval=48, const uint16_t le_scan_window=48,
+                                    const uint16_t conn_interval_min=0x000F, const uint16_t conn_interval_max=0x000F,
+                                    const uint16_t conn_latency=0x0000, const uint16_t supervision_timeout=number(HCIConstInt::LE_CONN_TIMEOUT_MS)/10);
 
             /**
              * Establish a HCI BDADDR_BREDR connection to this device.
              * <p>
-             * If this device's addressType is not BDADDR_BREDR, 0 is being returned.
+             * BT Core Spec v5.2: Vol 4, Part E HCI: 7.1.5 Create Connection command
              * </p>
              * <p>
-             * Returns true if the command has been accepted, otherwise false.
+             * If this device's addressType is not BDADDR_BREDR,
+             * HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM is being returned.
              * </p>
              * <p>
              * The actual new connection handle will be delivered asynchronous and
-             * the connection event can be caught via AdapterStatusListener::deviceConnected(..).
+             * the connection event can be caught via AdapterStatusListener::deviceConnected(..),
+             * or if failed via AdapterStatusListener::deviceDisconnected(..).
              * </p>
              * <p>
              * The device is tracked by the managing adapter.
              * </p>
+             * @return HCIStatusCode::SUCCESS if the command has been accepted, otherwise HCIStatusCode may disclose reason for rejection.
              */
-            bool connectBREDR(const uint16_t pkt_type=HCI_DM1 | HCI_DM3 | HCI_DM5 | HCI_DH1 | HCI_DH3 | HCI_DH5,
-                              const uint16_t clock_offset=0x0000, const uint8_t role_switch=0x01);
+            HCIStatusCode connectBREDR(const uint16_t pkt_type=HCI_DM1 | HCI_DM3 | HCI_DM5 | HCI_DH1 | HCI_DH3 | HCI_DH5,
+                                       const uint16_t clock_offset=0x0000, const uint8_t role_switch=0x01);
 
             /**
              * Establish a default HCI connection to this device, using certain default parameter.
              * <p>
-             * Depending on this device's addressType,
-             * either a BREDR (BDADDR_BREDR) or LE (BDADDR_LE_PUBLIC, BDADDR_LE_RANDOM) connection is attempted.
+             * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.12 LE Create Connection command <br>
+             * BT Core Spec v5.2: Vol 4, Part E HCI: 7.1.5 Create Connection command
              * </p>
              * <p>
-             * Returns true if the command has been accepted, otherwise false.
+             * Depending on this device's addressType,
+             * either a BREDR (BDADDR_BREDR) or LE (BDADDR_LE_PUBLIC, BDADDR_LE_RANDOM) connection is attempted.<br>
+             * If unacceptable, HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM is being returned.
              * </p>
              * <p>
              * The actual new connection handle will be delivered asynchronous and
-             * the connection event can be caught via AdapterStatusListener::deviceConnected(..).
-             * </p>
+             * the connection event can be caught via AdapterStatusListener::deviceConnected(..),
+             * or if failed via AdapterStatusListener::deviceDisconnected(..).
              * <p>
              * The device is tracked by the managing adapter.
              * </p>
+             * @return HCIStatusCode::SUCCESS if the command has been accepted, otherwise HCIStatusCode may disclose reason for rejection.
              */
-            bool connectDefault();
+            HCIStatusCode connectDefault();
 
 
             /** Return the HCI connection handle to the LE or BREDR peer, 0 if not connected. */
@@ -290,7 +297,7 @@ namespace direct_bt {
             /**
              * Disconnect the LE or BREDR peer's GATT and HCI connection.
              * <p>
-             * Returns true if the command has been accepted, otherwise false.
+             * BT Core Spec v5.2: Vol 4, Part E HCI: 7.1.6 Disconnect command
              * </p>
              * <p>
              * The actual disconnect event will be delivered asynchronous and
@@ -303,8 +310,9 @@ namespace direct_bt {
              * <p>
              * An open GATTHandler will also be closed via disconnectGATT()
              * </p>
+             * @return HCIStatusCode::SUCCESS if the command has been accepted, otherwise HCIStatusCode may disclose reason for rejection.
              */
-            bool disconnect(const HCIStatusCode reason=HCIStatusCode::REMOTE_USER_TERMINATED_CONNECTION ) {
+            HCIStatusCode disconnect(const HCIStatusCode reason=HCIStatusCode::REMOTE_USER_TERMINATED_CONNECTION ) {
                 return disconnect(false /* fromDisconnectCB */, false /* ioErrorCause */, reason);
             }
 
diff --git a/examples/direct_bt_scanner00/dbt_scanner00.cpp b/examples/direct_bt_scanner00/dbt_scanner00.cpp
index 5408eac2..09ca4d9d 100644
--- a/examples/direct_bt_scanner00/dbt_scanner00.cpp
+++ b/examples/direct_bt_scanner00/dbt_scanner00.cpp
@@ -222,8 +222,9 @@ int main(int argc, char *argv[])
             // (Without: Overall communication takes ~twice as long!!!)
             //
             if( doHCI_Connect ) {
-                if( 0 == device->connectDefault() ) {
-                    fprintf(stderr, "Connect: Failed %s\n", device->toString().c_str());
+                HCIStatusCode res;
+                if( ( res = device->connectDefault() ) != HCIStatusCode::SUCCESS ) {
+                    fprintf(stderr, "Connect: Failed res %s, %s\n", getHCIStatusCodeString(res).c_str(), device->toString().c_str());
                     // we tolerate the failed immediate connect, as it might happen at a later time
                 } else {
                     fprintf(stderr, "Connect: Success\n");
diff --git a/examples/direct_bt_scanner01/dbt_scanner01.cpp b/examples/direct_bt_scanner01/dbt_scanner01.cpp
index 720f68e0..bc3e8b2e 100644
--- a/examples/direct_bt_scanner01/dbt_scanner01.cpp
+++ b/examples/direct_bt_scanner01/dbt_scanner01.cpp
@@ -218,8 +218,9 @@ int main(int argc, char *argv[])
             // (Without: Overall communication takes ~twice as long!!!)
             //
             if( doHCI_Connect ) {
-                if( 0 == device->connectDefault() ) {
-                    fprintf(stderr, "Connect: Failed %s\n", device->toString().c_str());
+                HCIStatusCode res;
+                if( ( res = device->connectDefault() ) != HCIStatusCode::SUCCESS ) {
+                    fprintf(stderr, "Connect: Failed res %s, %s\n", getHCIStatusCodeString(res).c_str(), device->toString().c_str());
                     // we tolerate the failed immediate connect, as it might happen at a later time
                 } else {
                     fprintf(stderr, "Connect: Success\n");
diff --git a/examples/direct_bt_scanner10/dbt_scanner10.cpp b/examples/direct_bt_scanner10/dbt_scanner10.cpp
index 35d22efc..a428ba72 100644
--- a/examples/direct_bt_scanner10/dbt_scanner10.cpp
+++ b/examples/direct_bt_scanner10/dbt_scanner10.cpp
@@ -234,12 +234,14 @@ class MyGATTEventListener : public AssociatedGATTCharacteristicListener {
 static void connectDiscoveredDevice(std::shared_ptr<DBTDevice> device) {
     fprintf(stderr, "****** Connecting Device: Start %s\n", device->toString().c_str());
     device->getAdapter().stopDiscovery();
-    bool res = false;
+    HCIStatusCode res;
     if( !USE_WHITELIST ) {
         res = device->connectDefault();
+    } else {
+        res = HCIStatusCode::SUCCESS;
     }
-    fprintf(stderr, "****** Connecting Device: End result %d of %s\n", res, device->toString().c_str());
-    if( !USE_WHITELIST && 0 == devicesInProcessing.size() && !res ) {
+    fprintf(stderr, "****** Connecting Device: End result %s of %s\n", getHCIStatusCodeString(res).c_str(), device->toString().c_str());
+    if( !USE_WHITELIST && 0 == devicesInProcessing.size() && HCIStatusCode::SUCCESS != res ) {
         device->getAdapter().startDiscovery( true );
     }
 }
diff --git a/examples/java/AsyncTinyB.java b/examples/java/AsyncTinyB.java
index f70b890a..20313b33 100644
--- a/examples/java/AsyncTinyB.java
+++ b/examples/java/AsyncTinyB.java
@@ -6,6 +6,7 @@ import org.tinyb.BluetoothFactory;
 import org.tinyb.BluetoothGattCharacteristic;
 import org.tinyb.BluetoothGattService;
 import org.tinyb.BluetoothManager;
+import org.tinyb.HCIStatusCode;
 
 import java.lang.reflect.InvocationTargetException;
 import java.util.concurrent.TimeUnit;
@@ -87,7 +88,7 @@ public class AsyncTinyB {
         System.out.print("Found device: ");
         printDevice(sensor);
 
-        if (sensor.connect())
+        if ( HCIStatusCode.SUCCESS == sensor.connect() )
             System.out.println("Sensor with the provided address connected");
         else {
             System.out.println("Could not connect device.");
diff --git a/examples/java/HelloTinyB.java b/examples/java/HelloTinyB.java
index 77435de6..b6709b7f 100644
--- a/examples/java/HelloTinyB.java
+++ b/examples/java/HelloTinyB.java
@@ -11,6 +11,7 @@ import org.tinyb.BluetoothFactory;
 import org.tinyb.BluetoothGattCharacteristic;
 import org.tinyb.BluetoothGattService;
 import org.tinyb.BluetoothManager;
+import org.tinyb.HCIStatusCode;
 
 public class HelloTinyB {
     static boolean running = true;
@@ -149,7 +150,7 @@ public class HelloTinyB {
         System.out.print("Found device: ");
         printDevice(sensor);
 
-        if (sensor.connect())
+        if ( HCIStatusCode.SUCCESS == sensor.connect() )
             System.out.println("Sensor with the provided address connected");
         else {
             System.out.println("Could not connect device.");
diff --git a/examples/java/Notification.java b/examples/java/Notification.java
index c39a0a9e..5a2f5a8e 100644
--- a/examples/java/Notification.java
+++ b/examples/java/Notification.java
@@ -34,6 +34,7 @@ import org.tinyb.BluetoothGattCharacteristic;
 import org.tinyb.BluetoothGattService;
 import org.tinyb.BluetoothManager;
 import org.tinyb.BluetoothNotification;
+import org.tinyb.HCIStatusCode;
 
 class ValueNotification implements BluetoothNotification<byte[]> {
 
@@ -141,7 +142,7 @@ public class Notification {
         System.out.print("Found device: ");
         printDevice(sensor);
 
-        if (sensor.connect())
+        if ( HCIStatusCode.SUCCESS == sensor.connect() )
             System.out.println("Sensor with the provided address connected");
         else {
             System.out.println("Could not connect device.");
diff --git a/examples/java/ScannerTinyB00.java b/examples/java/ScannerTinyB00.java
index 7a45729a..e3b00648 100644
--- a/examples/java/ScannerTinyB00.java
+++ b/examples/java/ScannerTinyB00.java
@@ -37,6 +37,7 @@ import org.tinyb.BluetoothGattService;
 import org.tinyb.BluetoothManager;
 import org.tinyb.BluetoothNotification;
 import org.tinyb.BluetoothUtils;
+import org.tinyb.HCIStatusCode;
 
 public class ScannerTinyB00 {
     static {
@@ -165,13 +166,14 @@ public class ScannerTinyB00 {
             sensor.enableServicesResolvedNotifications(servicesResolvedNotification);
 
             final long t2;
-            if ( sensor.connect() ) {
+            final HCIStatusCode res;
+            if ( ( res = sensor.connect() ) == HCIStatusCode.SUCCESS ) {
                 t2 = System.currentTimeMillis();
-                System.err.println("Sensor connected in "+(t2-t1)+" ms");
+                System.err.println("Sensor connect command in "+(t2-t1)+" ms");
                 System.err.println("Sensor connectedNotification: "+connectedNotification.getValue());
             } else {
                 t2=0;
-                System.out.println("Could not connect device.");
+                System.out.println("Connect command failed, res "+res);
                 System.exit(-1);
             }
 
diff --git a/examples/java/ScannerTinyB01.java b/examples/java/ScannerTinyB01.java
index d6385167..4dda480c 100644
--- a/examples/java/ScannerTinyB01.java
+++ b/examples/java/ScannerTinyB01.java
@@ -275,13 +275,14 @@ public class ScannerTinyB01 {
 
                 final long t2 = BluetoothUtils.getCurrentMilliseconds();
                 final long t3;
-                if ( sensor.connect() ) {
+                HCIStatusCode res;
+                if ( ( res = sensor.connect() ) == HCIStatusCode.SUCCESS ) {
                     t3 = BluetoothUtils.getCurrentMilliseconds();
-                    System.err.println("Sensor connected: "+(t3-t2)+" ms, total "+(t3-t0)+" ms");
+                    System.err.println("Sensor connect issued: "+(t3-t2)+" ms, total "+(t3-t0)+" ms");
                     System.err.println("Sensor connectedNotification: "+connectedNotification.getValue());
                 } else {
                     t3 = BluetoothUtils.getCurrentMilliseconds();
-                    System.out.println("Could not connect device: "+(t3-t2)+" ms, total "+(t3-t0)+" ms");
+                    System.out.println("connect command failed, res "+res+": "+(t3-t2)+" ms, total "+(t3-t0)+" ms");
                     // we tolerate the failed immediate connect, as it might happen at a later time
                 }
 
diff --git a/examples/java/ScannerTinyB02.java b/examples/java/ScannerTinyB02.java
index d02ba9e7..a62c9742 100644
--- a/examples/java/ScannerTinyB02.java
+++ b/examples/java/ScannerTinyB02.java
@@ -282,13 +282,14 @@ public class ScannerTinyB02 {
 
                 final long t2 = BluetoothUtils.getCurrentMilliseconds();
                 final long t3;
-                if ( sensor.connect() ) {
+                HCIStatusCode res;
+                if ( (res = sensor.connect() ) == HCIStatusCode.SUCCESS ) {
                     t3 = BluetoothUtils.getCurrentMilliseconds();
-                    System.err.println("Sensor connected: "+(t3-t2)+" ms, total "+(t3-t0)+" ms");
+                    System.err.println("Sensor connect issued: "+(t3-t2)+" ms, total "+(t3-t0)+" ms");
                     System.err.println("Sensor connectedNotification: "+connectedNotification.getValue());
                 } else {
                     t3 = BluetoothUtils.getCurrentMilliseconds();
-                    System.out.println("Could not connect device: "+(t3-t2)+" ms, total "+(t3-t0)+" ms");
+                    System.out.println("connect command failed, res "+res+": "+(t3-t2)+" ms, total "+(t3-t0)+" ms");
                     // we tolerate the failed immediate connect, as it might happen at a later time
                 }
 
diff --git a/examples/java/ScannerTinyB10.java b/examples/java/ScannerTinyB10.java
index 1ec6afc3..730376d9 100644
--- a/examples/java/ScannerTinyB10.java
+++ b/examples/java/ScannerTinyB10.java
@@ -184,12 +184,14 @@ public class ScannerTinyB10 {
     private void connectDiscoveredDevice(final BluetoothDevice device) {
         println("****** Connecting Device: Start " + device.toString());
         device.getAdapter().stopDiscovery();
-        boolean res = false;
+        HCIStatusCode res;
         if( !USE_WHITELIST ) {
             res = device.connect();
+        } else {
+            res = HCIStatusCode.SUCCESS;
         }
-        println("****** Connecting Device: End result "+res+" of " + device.toString());
-        if( !USE_WHITELIST && 0 == devicesInProcessing.size() && !res ) {
+        println("****** Connecting Device Command, res "+res+": End result "+res+" of " + device.toString());
+        if( !USE_WHITELIST && 0 == devicesInProcessing.size() && HCIStatusCode.SUCCESS != res ) {
             device.getAdapter().startDiscovery( true );
         }
     }
diff --git a/java/direct_bt/tinyb/DBTDevice.java b/java/direct_bt/tinyb/DBTDevice.java
index 65301141..601a30a7 100644
--- a/java/direct_bt/tinyb/DBTDevice.java
+++ b/java/direct_bt/tinyb/DBTDevice.java
@@ -356,36 +356,36 @@ public class DBTDevice extends DBTObject implements BluetoothDevice
     public final boolean getConnected() { return isConnected.get(); }
 
     @Override
-    public final boolean disconnect() throws BluetoothException {
+    public final HCIStatusCode disconnect() throws BluetoothException {
         if( isConnected.get() ) {
-            return disconnectImpl(); // event callbacks will be generated by implementation
+            return HCIStatusCode.get( disconnectImpl() ); // event callbacks will be generated by implementation
         }
-        return false;
+        return HCIStatusCode.CONNECTION_TERMINATED_BY_LOCAL_HOST;
     }
-    private native boolean disconnectImpl() throws BluetoothException;
+    private native byte disconnectImpl() throws BluetoothException;
 
     @Override
-    public final boolean connect() throws BluetoothException {
+    public final HCIStatusCode connect() throws BluetoothException {
         if( !isConnected.get() ) {
-            return connectImpl(); // event callbacks will be generated by implementation
+            return HCIStatusCode.get( connectImpl() ); // event callbacks will be generated by implementation
         }
-        return false;
+        return HCIStatusCode.CONNECTION_ALREADY_EXISTS;
     }
-    private native boolean connectImpl() throws BluetoothException;
+    private native byte connectImpl() throws BluetoothException;
 
     @Override
-    public boolean connect(final short le_scan_interval, final short le_scan_window,
-                           final short conn_interval_min, final short conn_interval_max,
-                           final short conn_latency, final short timeout) {
+    public HCIStatusCode connect(final short le_scan_interval, final short le_scan_window,
+                                 final short conn_interval_min, final short conn_interval_max,
+                                 final short conn_latency, final short timeout) {
         if( !isConnected.get() ) {
             // event callbacks will be generated by implementation
-            return connectImpl(le_scan_interval, le_scan_window, conn_interval_min, conn_interval_max, conn_latency, timeout);
+            return HCIStatusCode.get( connectImpl(le_scan_interval, le_scan_window, conn_interval_min, conn_interval_max, conn_latency, timeout) );
         }
-        return false;
+        return HCIStatusCode.CONNECTION_ALREADY_EXISTS;
     }
-    private native boolean connectImpl(final short le_scan_interval, final short le_scan_window,
-                                       final short conn_interval_min, final short conn_interval_max,
-                                       final short conn_latency, final short timeout);
+    private native byte connectImpl(final short le_scan_interval, final short le_scan_window,
+                                    final short conn_interval_min, final short conn_interval_max,
+                                    final short conn_latency, final short timeout);
 
     /* DBT Java callbacks */
 
diff --git a/java/jni/direct_bt/DBTDevice.cxx b/java/jni/direct_bt/DBTDevice.cxx
index d28ac0c2..e426d2ce 100644
--- a/java/jni/direct_bt/DBTDevice.cxx
+++ b/java/jni/direct_bt/DBTDevice.cxx
@@ -295,16 +295,16 @@ void Java_direct_1bt_tinyb_DBTDevice_deleteImpl(JNIEnv *env, jobject obj, jlong
     }
 }
 
-jboolean Java_direct_1bt_tinyb_DBTDevice_disconnectImpl(JNIEnv *env, jobject obj)
+jbyte Java_direct_1bt_tinyb_DBTDevice_disconnectImpl(JNIEnv *env, jobject obj)
 {
     try {
         DBTDevice *device = getDBTObject<DBTDevice>(env, obj);
         JavaGlobalObj::check(device->getJavaObject(), E_FILE_LINE);
-        return device->disconnect() ? JNI_TRUE : JNI_FALSE;
+        return (jint) number( device->disconnect() );
     } catch(...) {
         rethrow_and_raise_java_exception(env);
     }
-    return JNI_FALSE;
+    return (jbyte) number(HCIStatusCode::INTERNAL_FAILURE);
 }
 
 jboolean Java_direct_1bt_tinyb_DBTDevice_removeImpl(JNIEnv *env, jobject obj)
@@ -319,28 +319,27 @@ jboolean Java_direct_1bt_tinyb_DBTDevice_removeImpl(JNIEnv *env, jobject obj)
     return JNI_TRUE;
 }
 
-jboolean Java_direct_1bt_tinyb_DBTDevice_connectImpl__(JNIEnv *env, jobject obj)
+jbyte Java_direct_1bt_tinyb_DBTDevice_connectImpl__(JNIEnv *env, jobject obj)
 {
     try {
         DBTDevice *device = getDBTObject<DBTDevice>(env, obj);
         JavaGlobalObj::check(device->getJavaObject(), E_FILE_LINE);
-        bool res = device->connectDefault();
-        return res ? JNI_TRUE : JNI_FALSE;
+        return (jbyte) number( device->connectDefault() );
     } catch(...) {
         rethrow_and_raise_java_exception(env);
     }
-    return JNI_FALSE;
+    return (jbyte) number(HCIStatusCode::INTERNAL_FAILURE);
 }
 
-jboolean Java_direct_1bt_tinyb_DBTDevice_connectImpl__SSSSSS(JNIEnv *env, jobject obj,
-                                                             jshort interval, jshort window,
-                                                             jshort min_interval, jshort max_interval,
-                                                             jshort latency, jshort timeout)
+jbyte Java_direct_1bt_tinyb_DBTDevice_connectImpl__SSSSSS(JNIEnv *env, jobject obj,
+                                                          jshort interval, jshort window,
+                                                          jshort min_interval, jshort max_interval,
+                                                          jshort latency, jshort timeout)
 {
     try {
         DBTDevice *device = getDBTObject<DBTDevice>(env, obj);
         JavaGlobalObj::check(device->getJavaObject(), E_FILE_LINE);
-        bool res;
+        HCIStatusCode res;
         switch( device->addressType ) {
             case BDAddressType::BDADDR_LE_PUBLIC:
                 /* fall through intended */
@@ -351,11 +350,11 @@ jboolean Java_direct_1bt_tinyb_DBTDevice_connectImpl__SSSSSS(JNIEnv *env, jobjec
                 res = device->connectDefault();
                 break;
         }
-        return res ? JNI_TRUE : JNI_FALSE;
+        return (jbyte) number(res);
     } catch(...) {
         rethrow_and_raise_java_exception(env);
     }
-    return JNI_FALSE;
+    return (jbyte) number(HCIStatusCode::INTERNAL_FAILURE);
 }
 
 //
diff --git a/java/jni/tinyb/DBusDevice.cxx b/java/jni/tinyb/DBusDevice.cxx
index 5eb8581b..f810ef9d 100644
--- a/java/jni/tinyb/DBusDevice.cxx
+++ b/java/jni/tinyb/DBusDevice.cxx
@@ -72,7 +72,7 @@ jobject Java_tinyb_dbus_DBusDevice_clone(JNIEnv *env, jobject obj)
     return nullptr;
 }
 
-jboolean Java_tinyb_dbus_DBusDevice_disconnect(JNIEnv *env, jobject obj)
+jboolean Java_tinyb_dbus_DBusDevice_disconnectImpl(JNIEnv *env, jobject obj)
 {
     try {
         BluetoothDevice *obj_device = getInstance<BluetoothDevice>(env, obj);
@@ -131,7 +131,7 @@ jboolean Java_tinyb_dbus_DBusDevice_connectAsyncFinish(JNIEnv *env, jobject obj)
     return JNI_FALSE;
 }
 
-jboolean Java_tinyb_dbus_DBusDevice_connect(JNIEnv *env, jobject obj)
+jboolean Java_tinyb_dbus_DBusDevice_connectImpl(JNIEnv *env, jobject obj)
 {
     try {
         BluetoothDevice *obj_device = getInstance<BluetoothDevice>(env, obj);
diff --git a/java/org/tinyb/BluetoothDevice.java b/java/org/tinyb/BluetoothDevice.java
index fe84cce8..2794bde2 100644
--- a/java/org/tinyb/BluetoothDevice.java
+++ b/java/org/tinyb/BluetoothDevice.java
@@ -64,25 +64,83 @@ public interface BluetoothDevice extends BluetoothObject
       */
     BluetoothGattService find(String UUID);
 
-    /* D-Bus method calls: */
-    /** The connection to this device is removed, removing all connected
-      * profiles.
-      * @return TRUE if the device disconnected
-      */
-    boolean disconnect() throws BluetoothException;
+    /* Bluetooth method calls: */
 
-    /** A connection to this device is established, connecting each profile
-      * flagged as auto-connectable.
-      * @return TRUE if the device connected
-      * @see #connect(short, short, short, short, short, short)
-      */
-    boolean connect() throws BluetoothException;
+    /**
+     * <b>direct_bt.tinyb</b>: Disconnect the LE or BREDR peer's GATT and HCI connection.
+     * <p>
+     * BT Core Spec v5.2: Vol 4, Part E HCI: 7.1.6 Disconnect command
+     * </p>
+     * <p>
+     * The actual disconnect event will be delivered asynchronous and
+     * the connection event can be caught via AdapterStatusListener::deviceDisconnected(..).
+     * If unacceptable, {@link HCIStatusCode#UNACCEPTABLE_CONNECTION_PARAM} is being returned.
+     * </p>
+     * <p>
+     * The device will be removed from the managing adapter's connected devices
+     * when {@link AdapterStatusListener#deviceDisconnected(BluetoothDevice, HCIStatusCode, long)} has been received.
+     * </p>
+     * <p>
+     * Any open GATT connection will be closed as well.
+     * </p>
+     * <p>
+     * <b>tinyb.dbus</b> The connection to this device is removed, removing all connected
+     * profiles.
+     * </p>
+     * @return {@link HCIStatusCode#SUCCESS} if the command has been accepted, otherwise {@link HCIStatusCode} may disclose reason for rejection.
+     * @since 2.1.0 change API, i.e. return value from boolean to HCIStatusCode in favor of <i>direct_bt</i>
+     */
+    HCIStatusCode disconnect() throws BluetoothException;
+
+    /**
+     * <b>direct_bt.tinyb</b>: Establish a default HCI connection to this device, using certain default parameter.
+     * <p>
+     * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.12 LE Create Connection command <br>
+     * BT Core Spec v5.2: Vol 4, Part E HCI: 7.1.5 Create Connection command
+     * </p>
+     * <p>
+     * Depending on this device's addressType,
+     * either a BREDR (BDADDR_BREDR) or LE (BDADDR_LE_PUBLIC, BDADDR_LE_RANDOM) connection is attempted.<br>
+     * If unacceptable, {@link HCIStatusCode#UNACCEPTABLE_CONNECTION_PARAM} is being returned.
+     * </p>
+     * <p>
+     * The actual new connection handle will be delivered asynchronous and
+     * the connection event can be caught via {@link AdapterStatusListener#deviceConnected(BluetoothDevice, long)},
+     * or if failed via {@link AdapterStatusListener#deviceDisconnected(BluetoothDevice, HCIStatusCode, long)}.
+     * </p>
+     * <p>
+     * The device is tracked by the managing adapter.
+     * </p>
+     * <p>
+     * <b>tinyb.dbus</b>: A connection to this device is established, connecting each profile
+     * flagged as auto-connectable.
+     * </p>
+     * @return {@link HCIStatusCode#SUCCESS} if the command has been accepted, otherwise {@link HCIStatusCode} may disclose reason for rejection.
+     * @see #connect(short, short, short, short, short, short)
+     * @since 2.1.0 change API, i.e. return value from boolean to HCIStatusCode in favor of <i>direct_bt</i>
+     */
+    HCIStatusCode connect() throws BluetoothException;
 
     /**
-     * A connection to this device is established, see {@link #connect()}.
+     * Establish a HCI BDADDR_LE_PUBLIC or BDADDR_LE_RANDOM connection to this device.
      * <p>
-     * The given LE connection parameter will be used instead of the Bluetooth implementation defaults,
-     * if this device is of type {@link BluetoothAddressType#BDADDR_LE_PUBLIC} or {@link BluetoothAddressType#BDADDR_LE_RANDOM}.
+     * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.12 LE Create Connection command
+     * </p>
+     * <p>
+     * If this device's {@link #getAddressType()} is not BDADDR_LE_PUBLIC or BDADDR_LE_RANDOM,
+     * {@link HCIStatusCode#UNACCEPTABLE_CONNECTION_PARAM} is being returned.
+     * </p>
+     * <p>
+     * The actual new connection handle will be delivered asynchronous and
+     * the connection event can be caught via {@link AdapterStatusListener#deviceConnected(BluetoothDevice, long)},
+     * or if failed via {@link AdapterStatusListener#deviceDisconnected(BluetoothDevice, HCIStatusCode, long)}.
+     * </p>
+     * <p>
+     * The device is tracked by the managing adapter.
+     * </p>
+     * <p>
+     * Default parameter values are chosen for using public address resolution
+     * and usual connection latency, interval etc.
      * </p>
      * <p>
      * Set window to the same value as the interval, enables continuous scanning.
@@ -93,15 +151,16 @@ public interface BluetoothDevice extends BluetoothObject
      * @param conn_interval_min in units of 1.25ms, default value 15 for 19.75ms
      * @param conn_interval_max in units of 1.25ms, default value 15 for 19.75ms
      * @param conn_latency slave latency in units of connection events, default value 0
-     * @param timeout in units of 10ms, default value 1000 for 10000ms or 10s.
-     * @return {@code true} if successful, otherwise {@code false}.
+     * @param supervision_timeout in units of 10ms, default value 1000 for 10000ms or 10s.
+     * @return {@link HCIStatusCode#SUCCESS} if the command has been accepted, otherwise {@link HCIStatusCode} may disclose reason for rejection.
      *
      * @see #connect()
-     * @since 2.0.0
+     * @since 2.1.0 change API, i.e. return value from boolean to HCIStatusCode in favor of <i>direct_bt</i>
+     * @implNote not implemented in <b>tinyb.dbus</b>
      */
-    public boolean connect(final short le_scan_interval, final short le_scan_window,
-                           final short conn_interval_min, final short conn_interval_max,
-                           final short conn_latency, final short timeout);
+    HCIStatusCode connect(final short le_scan_interval, final short le_scan_window,
+                          final short conn_interval_min, final short conn_interval_max,
+                          final short conn_latency, final short timeout);
 
 
     /** Connects a specific profile available on the device, given by UUID
@@ -193,7 +252,7 @@ public interface BluetoothDevice extends BluetoothObject
      * determining whether the device is {@link BluetoothAddressType#BDADDR_BREDR}
      * or an LE device, {@link BluetoothAddressType#BDADDR_LE_PUBLIC} or {@link BluetoothAddressType#BDADDR_LE_RANDOM}.
      * @since 2.0.0
-     * @implNote not implemented in tinyb.dbus, returns {@link BluetoothAddressType#BDADDR_LE_PUBLIC}
+     * @implNote not implemented in <b>tinyb.dbus</b>, returns {@link BluetoothAddressType#BDADDR_LE_PUBLIC}
      */
     BluetoothAddressType getAddressType();
 
@@ -208,7 +267,7 @@ public interface BluetoothDevice extends BluetoothObject
      * method shall return {@link BLERandomAddressType#UNDEFINED}.
      * </p>
      * @since 2.0.0
-     * @implNote not implemented in tinyb.dbus, returns {@link BLERandomAddressType#UNDEFINED}
+     * @implNote not implemented in <b>tinyb.dbus</b>, returns {@link BLERandomAddressType#UNDEFINED}
      */
     BLERandomAddressType getBLERandomAddressType();
 
@@ -454,7 +513,7 @@ public interface BluetoothDevice extends BluetoothObject
      * @see BluetoothGattCharacteristic#configNotificationIndication(boolean, boolean, boolean[])
      * @see BluetoothGattCharacteristic#enableNotificationOrIndication(boolean[])
      * @since 2.0.0
-     * @implNote not implemented in tinyb.dbus
+     * @implNote not implemented in <b>tinyb.dbus</b>
      */
     public boolean addCharacteristicListener(final GATTCharacteristicListener listener)
         throws IllegalStateException;
@@ -467,7 +526,7 @@ public interface BluetoothDevice extends BluetoothObject
      * @param listener A {@link GATTCharacteristicListener} instance
      * @return true if the given listener is an element of the list and has been removed, otherwise false.
      * @since 2.0.0
-     * @implNote not implemented in tinyb.dbus
+     * @implNote not implemented in <b>tinyb.dbus</b>
      */
     public boolean removeCharacteristicListener(final GATTCharacteristicListener l);
 
@@ -480,7 +539,7 @@ public interface BluetoothDevice extends BluetoothObject
      * @param associatedCharacteristic the match criteria to remove any GATTCharacteristicListener from the list
      * @return number of removed listener.
      * @since 2.0.0
-     * @implNote not implemented in tinyb.dbus
+     * @implNote not implemented in <b>tinyb.dbus</b>
      */
     public int removeAllAssociatedCharacteristicListener(final BluetoothGattCharacteristic associatedCharacteristic);
 
@@ -488,7 +547,7 @@ public interface BluetoothDevice extends BluetoothObject
      * Remove all {@link GATTCharacteristicListener} from the list.
      * @return number of removed listener.
      * @since 2.0.0
-     * @implNote not implemented in tinyb.dbus
+     * @implNote not implemented in <b>tinyb.dbus</b>
      */
     public int removeAllCharacteristicListener();
 }
diff --git a/java/tinyb/dbus/DBusDevice.java b/java/tinyb/dbus/DBusDevice.java
index 5bbb8f7d..225b01d0 100644
--- a/java/tinyb/dbus/DBusDevice.java
+++ b/java/tinyb/dbus/DBusDevice.java
@@ -42,6 +42,7 @@ import org.tinyb.BluetoothNotification;
 import org.tinyb.BluetoothType;
 import org.tinyb.BluetoothUtils;
 import org.tinyb.GATTCharacteristicListener;
+import org.tinyb.HCIStatusCode;
 
 public class DBusDevice extends DBusObject implements BluetoothDevice
 {
@@ -76,15 +77,22 @@ public class DBusDevice extends DBusObject implements BluetoothDevice
     /* D-Bus method calls: */
 
     @Override
-    public native boolean disconnect() throws BluetoothException;
+    public final HCIStatusCode disconnect() throws BluetoothException {
+        return disconnectImpl() ? HCIStatusCode.SUCCESS : HCIStatusCode.UNSPECIFIED_ERROR ;
+    }
+    private native boolean disconnectImpl() throws BluetoothException;
+
 
     @Override
-    public native boolean connect() throws BluetoothException;
+    public final HCIStatusCode connect() throws BluetoothException {
+        return connectImpl() ? HCIStatusCode.SUCCESS : HCIStatusCode.UNSPECIFIED_ERROR ;
+    }
+    private native boolean connectImpl() throws BluetoothException;
 
     @Override
-    public boolean connect(final short interval, final short window,
-                           final short min_interval, final short max_interval,
-                           final short latency, final short timeout) {
+    public HCIStatusCode connect(final short interval, final short window,
+                                 final short min_interval, final short max_interval,
+                                 final short latency, final short timeout) {
         return connect(); // FIXME connection params ...
     }
 
diff --git a/src/direct_bt/DBTDevice.cpp b/src/direct_bt/DBTDevice.cpp
index 8d1056b9..898feca4 100644
--- a/src/direct_bt/DBTDevice.cpp
+++ b/src/direct_bt/DBTDevice.cpp
@@ -260,9 +260,9 @@ std::shared_ptr<ConnectionInfo> DBTDevice::getConnectionInfo() {
     return connInfo;
 }
 
-bool DBTDevice::connectLE(uint16_t le_scan_interval, uint16_t le_scan_window,
-                          uint16_t conn_interval_min, uint16_t conn_interval_max,
-                          uint16_t conn_latency, uint16_t supervision_timeout)
+HCIStatusCode DBTDevice::connectLE(uint16_t le_scan_interval, uint16_t le_scan_window,
+                                   uint16_t conn_interval_min, uint16_t conn_interval_max,
+                                   uint16_t conn_latency, uint16_t supervision_timeout)
 {
     const std::lock_guard<std::recursive_mutex> lock_conn(mtx_connect); // RAII-style acquire and relinquish via destructor
     adapter.checkValid();
@@ -282,13 +282,13 @@ bool DBTDevice::connectLE(uint16_t le_scan_interval, uint16_t le_scan_window,
                         hci_own_mac_type = HCILEOwnAddressType::RANDOM;
                         ERR_PRINT("LE Random address type '%s' not supported yet: %s",
                                 getBLERandomAddressTypeString(leRandomAddressType).c_str(), toString().c_str());
-                        return false;
+                        return HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM;
                     case BLERandomAddressType::RESOLVABLE_PRIVAT:
                         hci_peer_mac_type = HCILEPeerAddressType::PUBLIC_IDENTITY;
                         hci_own_mac_type = HCILEOwnAddressType::RESOLVABLE_OR_PUBLIC;
                         ERR_PRINT("LE Random address type '%s' not supported yet: %s",
                                 getBLERandomAddressTypeString(leRandomAddressType).c_str(), toString().c_str());
-                        return false;
+                        return HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM;
                     case BLERandomAddressType::STATIC_PUBLIC:
                         // FIXME: This only works for a static random address not changing at all,
                         // i.e. between power-cycles - hence a temporary hack.
@@ -299,19 +299,19 @@ bool DBTDevice::connectLE(uint16_t le_scan_interval, uint16_t le_scan_window,
                     default: {
                         ERR_PRINT("Can't connectLE to LE Random address type '%s': %s",
                                 getBLERandomAddressTypeString(leRandomAddressType).c_str(), toString().c_str());
-                        return false;
+                        return HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM;
                     }
                 }
             } break;
         default: {
                 ERR_PRINT("Can't connectLE to address type '%s': %s", getBDAddressTypeString(addressType).c_str(), toString().c_str());
-                return false;
+                return HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM;
             }
     }
 
     if( isConnected ) {
         ERR_PRINT("DBTDevice::connectLE: Already connected: %s", toString().c_str());
-        return false;
+        return HCIStatusCode::CONNECTION_ALREADY_EXISTS;
     }
 
     HCIStatusCode status = adapter.getHCI()->le_create_conn(address,
@@ -337,31 +337,28 @@ bool DBTDevice::connectLE(uint16_t le_scan_interval, uint16_t le_scan_window,
                 getHCILEPeerAddressTypeString(hci_peer_mac_type).c_str(),
                 getHCILEOwnAddressTypeString(hci_own_mac_type).c_str(),
                 toString().c_str());
-        return false;
-    }
-    if ( HCIStatusCode::SUCCESS != status ) {
+    } else if ( HCIStatusCode::SUCCESS != status ) {
         ERR_PRINT("DBTDevice::connectLE: Could not create connection: status 0x%2.2X (%s), errno %d %s, hci-atype[peer %s, own %s] on %s",
                 static_cast<uint8_t>(status), getHCIStatusCodeString(status).c_str(), errno, strerror(errno),
                 getHCILEPeerAddressTypeString(hci_peer_mac_type).c_str(),
                 getHCILEOwnAddressTypeString(hci_own_mac_type).c_str(),
                 toString().c_str());
-        return false;
     }
-    return true;
+    return status;
 }
 
-bool DBTDevice::connectBREDR(const uint16_t pkt_type, const uint16_t clock_offset, const uint8_t role_switch)
+HCIStatusCode DBTDevice::connectBREDR(const uint16_t pkt_type, const uint16_t clock_offset, const uint8_t role_switch)
 {
     const std::lock_guard<std::recursive_mutex> lock_conn(mtx_connect); // RAII-style acquire and relinquish via destructor
     adapter.checkValid();
 
     if( isConnected ) {
         ERR_PRINT("DBTDevice::connectBREDR: Already connected: %s", toString().c_str());
-        return false;
+        return HCIStatusCode::CONNECTION_ALREADY_EXISTS;
     }
     if( !isBREDRAddressType() ) {
         ERR_PRINT("DBTDevice::connectBREDR: Not a BDADDR_BREDR address: %s", toString().c_str());
-        return false;
+        return HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM;
     }
 
     HCIStatusCode status = adapter.getHCI()->create_conn(address, pkt_type, clock_offset, role_switch);
@@ -369,12 +366,11 @@ bool DBTDevice::connectBREDR(const uint16_t pkt_type, const uint16_t clock_offse
     if ( HCIStatusCode::SUCCESS != status ) {
         ERR_PRINT("DBTDevice::connectBREDR: Could not create connection: status 0x%2.2X (%s), errno %d %s on %s",
                 static_cast<uint8_t>(status), getHCIStatusCodeString(status).c_str(), errno, strerror(errno), toString().c_str());
-        return false;
     }
-    return true;
+    return status;
 }
 
-bool DBTDevice::connectDefault()
+HCIStatusCode DBTDevice::connectDefault()
 {
     switch( addressType ) {
         case BDAddressType::BDADDR_LE_PUBLIC:
@@ -385,7 +381,7 @@ bool DBTDevice::connectDefault()
             return connectBREDR();
         default:
             ERR_PRINT("DBTDevice::connectDefault: Not a valid address type: %s", toString().c_str());
-            return false;
+            return HCIStatusCode::UNACCEPTABLE_CONNECTION_PARAM;
     }
 }
 
@@ -409,7 +405,7 @@ void DBTDevice::notifyDisconnected() {
     hciConnHandle = 0;
 }
 
-bool DBTDevice::disconnect(const bool fromDisconnectCB, const bool ioErrorCause, const HCIStatusCode reason) {
+HCIStatusCode DBTDevice::disconnect(const bool fromDisconnectCB, const bool ioErrorCause, const HCIStatusCode reason) {
     // Avoid disconnect re-entry -> potential deadlock
     bool expConn = true; // C++11, exp as value since C++20
     if( !allowDisconnect.compare_exchange_strong(expConn, false) ) {
@@ -418,7 +414,7 @@ bool DBTDevice::disconnect(const bool fromDisconnectCB, const bool ioErrorCause,
                 allowDisconnect.load(), isConnected.load(), fromDisconnectCB, ioErrorCause,
                 static_cast<uint8_t>(reason), getHCIStatusCodeString(reason).c_str(),
                 (nullptr != gattHandler), uint16HexString(hciConnHandle).c_str());
-        return false;
+        return HCIStatusCode::CONNECTION_TERMINATED_BY_LOCAL_HOST;
     }
     // Lock to avoid other threads connecting while disconnecting
     const std::lock_guard<std::recursive_mutex> lock_conn(mtx_connect); // RAII-style acquire and relinquish via destructor
@@ -430,9 +426,10 @@ bool DBTDevice::disconnect(const bool fromDisconnectCB, const bool ioErrorCause,
     disconnectGATT();
 
     std::shared_ptr<HCIHandler> hci = adapter.getHCI();
-    bool res = false;
+    HCIStatusCode res = HCIStatusCode::UNSPECIFIED_ERROR;
 
     if( !isConnected ) {
+        res = HCIStatusCode::CONNECTION_TERMINATED_BY_LOCAL_HOST;
         goto exit;
     }
 
@@ -445,10 +442,9 @@ bool DBTDevice::disconnect(const bool fromDisconnectCB, const bool ioErrorCause,
         goto exit;
     }
 
-    if( HCIStatusCode::SUCCESS != hci->disconnect(ioErrorCause, hciConnHandle.load(), address, addressType, reason) ) {
+    res = hci->disconnect(ioErrorCause, hciConnHandle.load(), address, addressType, reason);
+    if( HCIStatusCode::SUCCESS != res ) {
         DBG_PRINT("DBTDevice::disconnect: handle 0x%X, errno %d %s", hciConnHandle.load(), errno, strerror(errno));
-    } else {
-        res = true;
     }
 
 exit: