diff --git a/libsysutils/src/FrameworkListener.cpp b/libsysutils/src/FrameworkListener.cpp
index 87e2684..835e226 100644
--- a/libsysutils/src/FrameworkListener.cpp
+++ b/libsysutils/src/FrameworkListener.cpp
@@ -42,7 +42,7 @@
 
 FrameworkListener::FrameworkListener(int sock) :
                             SocketListener(sock, true) {
-    init(NULL, false);
+    init(nullptr, false);
 }
 
 void FrameworkListener::init(const char *socketName UNUSED, bool withSeq) {
@@ -154,7 +154,7 @@
             if (!haveCmdNum) {
                 char *endptr;
                 int cmdNum = (int)strtol(tmp, &endptr, 0);
-                if (endptr == NULL || *endptr != '\0') {
+                if (endptr == nullptr || *endptr != '\0') {
                     cli->sendMsg(500, "Invalid sequence number", false);
                     goto out;
                 }
diff --git a/libsysutils/src/NetlinkEvent.cpp b/libsysutils/src/NetlinkEvent.cpp
index f0c66ec..24ea7aa 100644
--- a/libsysutils/src/NetlinkEvent.cpp
+++ b/libsysutils/src/NetlinkEvent.cpp
@@ -45,8 +45,8 @@
 NetlinkEvent::NetlinkEvent() {
     mAction = Action::kUnknown;
     memset(mParams, 0, sizeof(mParams));
-    mPath = NULL;
-    mSubsystem = NULL;
+    mPath = nullptr;
+    mSubsystem = nullptr;
 }
 
 NetlinkEvent::~NetlinkEvent() {
@@ -89,7 +89,7 @@
         NL_EVENT_RTM_NAME(LOCAL_QLOG_NL_EVENT);
         NL_EVENT_RTM_NAME(LOCAL_NFLOG_PACKET);
         default:
-            return NULL;
+            return nullptr;
     }
 #undef NL_EVENT_RTM_NAME
 }
@@ -158,7 +158,7 @@
  */
 bool NetlinkEvent::parseIfAddrMessage(const struct nlmsghdr *nh) {
     struct ifaddrmsg *ifaddr = (struct ifaddrmsg *) NLMSG_DATA(nh);
-    struct ifa_cacheinfo *cacheinfo = NULL;
+    struct ifa_cacheinfo *cacheinfo = nullptr;
     char addrstr[INET6_ADDRSTRLEN] = "";
     char ifname[IFNAMSIZ] = "";
 
@@ -286,7 +286,7 @@
 bool NetlinkEvent::parseNfPacketMessage(struct nlmsghdr *nh) {
     int uid = -1;
     int len = 0;
-    char* raw = NULL;
+    char* raw = nullptr;
 
     struct nlattr* uid_attr = findNlAttr(nh, sizeof(struct genlmsghdr), NFULA_UID);
     if (uid_attr) {
@@ -584,7 +584,7 @@
         (prefixlen == 0 || !memcmp(str, prefix, prefixlen))) {
         return str + prefixlen;
     } else {
-        return NULL;
+        return nullptr;
     }
 }
 
@@ -625,16 +625,16 @@
             first = 0;
         } else {
             const char* a;
-            if ((a = HAS_CONST_PREFIX(s, end, "ACTION=")) != NULL) {
+            if ((a = HAS_CONST_PREFIX(s, end, "ACTION=")) != nullptr) {
                 if (!strcmp(a, "add"))
                     mAction = Action::kAdd;
                 else if (!strcmp(a, "remove"))
                     mAction = Action::kRemove;
                 else if (!strcmp(a, "change"))
                     mAction = Action::kChange;
-            } else if ((a = HAS_CONST_PREFIX(s, end, "SEQNUM=")) != NULL) {
+            } else if ((a = HAS_CONST_PREFIX(s, end, "SEQNUM=")) != nullptr) {
                 mSeq = atoi(a);
-            } else if ((a = HAS_CONST_PREFIX(s, end, "SUBSYSTEM=")) != NULL) {
+            } else if ((a = HAS_CONST_PREFIX(s, end, "SUBSYSTEM=")) != nullptr) {
                 mSubsystem = strdup(a);
             } else if (param_idx < NL_PARAMS_MAX) {
                 mParams[param_idx++] = strdup(s);
@@ -656,14 +656,14 @@
 
 const char *NetlinkEvent::findParam(const char *paramName) {
     size_t len = strlen(paramName);
-    for (int i = 0; i < NL_PARAMS_MAX && mParams[i] != NULL; ++i) {
+    for (int i = 0; i < NL_PARAMS_MAX && mParams[i] != nullptr; ++i) {
         const char *ptr = mParams[i] + len;
         if (!strncmp(mParams[i], paramName, len) && *ptr == '=')
             return ++ptr;
     }
 
     SLOGE("NetlinkEvent::FindParam(): Parameter '%s' not found", paramName);
-    return NULL;
+    return nullptr;
 }
 
 nlattr* NetlinkEvent::findNlAttr(const nlmsghdr* nh, size_t hdrlen, uint16_t attr) {
diff --git a/libsysutils/src/SocketClient.cpp b/libsysutils/src/SocketClient.cpp
index 971f908..0625db7 100644
--- a/libsysutils/src/SocketClient.cpp
+++ b/libsysutils/src/SocketClient.cpp
@@ -42,8 +42,8 @@
     mSocket = socket;
     mSocketOwned = owned;
     mUseCmdNum = useCmdNum;
-    pthread_mutex_init(&mWriteMutex, NULL);
-    pthread_mutex_init(&mRefCountMutex, NULL);
+    pthread_mutex_init(&mWriteMutex, nullptr);
+    pthread_mutex_init(&mRefCountMutex, nullptr);
     mPid = -1;
     mUid = -1;
     mGid = -1;
@@ -135,9 +135,9 @@
     const char *end = arg + len;
     char *oldresult;
 
-    if(result == NULL) {
+    if(result == nullptr) {
         SLOGW("malloc error (%s)", strerror(errno));
-        return NULL;
+        return nullptr;
     }
 
     *(current++) = '"';
diff --git a/libsysutils/src/SocketListener.cpp b/libsysutils/src/SocketListener.cpp
index 3f8f3db..0c8a688 100644
--- a/libsysutils/src/SocketListener.cpp
+++ b/libsysutils/src/SocketListener.cpp
@@ -39,7 +39,7 @@
 }
 
 SocketListener::SocketListener(int socketFd, bool listen) {
-    init(NULL, socketFd, listen, false);
+    init(nullptr, socketFd, listen, false);
 }
 
 SocketListener::SocketListener(const char *socketName, bool listen, bool useCmdNum) {
@@ -51,7 +51,7 @@
     mSocketName = socketName;
     mSock = socketFd;
     mUseCmdNum = useCmdNum;
-    pthread_mutex_init(&mClientsLock, NULL);
+    pthread_mutex_init(&mClientsLock, nullptr);
     mClients = new SocketClientCollection();
 }
 
@@ -102,7 +102,7 @@
         return -1;
     }
 
-    if (pthread_create(&mThread, NULL, SocketListener::threadStart, this)) {
+    if (pthread_create(&mThread, nullptr, SocketListener::threadStart, this)) {
         SLOGE("pthread_create (%s)", strerror(errno));
         return -1;
     }
@@ -147,8 +147,8 @@
     SocketListener *me = reinterpret_cast<SocketListener *>(obj);
 
     me->runListener();
-    pthread_exit(NULL);
-    return NULL;
+    pthread_exit(nullptr);
+    return nullptr;
 }
 
 void SocketListener::runListener() {
@@ -183,7 +183,7 @@
         }
         pthread_mutex_unlock(&mClientsLock);
         SLOGV("mListen=%d, max=%d, mSocketName=%s", mListen, max, mSocketName);
-        if ((rc = select(max + 1, &read_fds, NULL, NULL, NULL)) < 0) {
+        if ((rc = select(max + 1, &read_fds, nullptr, nullptr, nullptr)) < 0) {
             if (errno == EINTR)
                 continue;
             SLOGE("select failed (%s) mListen=%d, max=%d", strerror(errno), mListen, max);