diff --git a/lib/BlockArray.cpp b/lib/BlockArray.cpp
index e4ccf8d..3ffd83f 100644
--- a/lib/BlockArray.cpp
+++ b/lib/BlockArray.cpp
@@ -41,9 +41,9 @@ BlockArray::BlockArray()
         : size(0),
         current(size_t(-1)),
         index(size_t(-1)),
-        lastmap(0),
+        lastmap(nullptr),
         lastmap_index(size_t(-1)),
-        lastblock(0), ion(-1),
+        lastblock(nullptr), ion(-1),
         length(0)
 {
     // lastmap_index = index = current = size_t(-1);
@@ -138,7 +138,7 @@ const Block * BlockArray::at(size_t i)
 
     if (i > index) {
         qDebug() << "BlockArray::at() i > index\n";
-        return 0;
+        return nullptr;
     }
 
 //     if (index - i >= length) {
@@ -151,11 +151,11 @@ const Block * BlockArray::at(size_t i)
     Q_ASSERT(j < size);
     unmap();
 
-    Block * block = (Block *)mmap(0, blocksize, PROT_READ, MAP_PRIVATE, ion, j * blocksize);
+    Block * block = (Block *)mmap(nullptr, blocksize, PROT_READ, MAP_PRIVATE, ion, j * blocksize);
 
     if (block == (Block *)-1) {
         perror("mmap");
-        return 0;
+        return nullptr;
     }
 
     lastmap = block;
@@ -172,7 +172,7 @@ void BlockArray::unmap()
             perror("munmap");
         }
     }
-    lastmap = 0;
+    lastmap = nullptr;
     lastmap_index = size_t(-1);
 }
 
@@ -193,7 +193,7 @@ bool BlockArray::setHistorySize(size_t newsize)
 
     if (!newsize) {
         delete lastblock;
-        lastblock = 0;
+        lastblock = nullptr;
         if (ion >= 0) {
             close(ion);
         }
diff --git a/lib/ColorScheme.cpp b/lib/ColorScheme.cpp
index c9cc851..4ed61e1 100644
--- a/lib/ColorScheme.cpp
+++ b/lib/ColorScheme.cpp
@@ -122,25 +122,25 @@ const char* const ColorScheme::translatedColorNames[TABLE_COLORS] =
 
 ColorScheme::ColorScheme()
 {
-    _table = 0;
-    _randomTable = 0;
+    _table = nullptr;
+    _randomTable = nullptr;
     _opacity = 1.0;
 }
 ColorScheme::ColorScheme(const ColorScheme& other)
       : _opacity(other._opacity)
-       ,_table(0)
-       ,_randomTable(0)
+       ,_table(nullptr)
+       ,_randomTable(nullptr)
 {
     setName(other.name());
     setDescription(other.description());
 
-    if ( other._table != 0 )
+    if ( other._table != nullptr )
     {
         for ( int i = 0 ; i < TABLE_COLORS ; i++ )
             setColorTableEntry(i,other._table[i]);
     }
 
-    if ( other._randomTable != 0 )
+    if ( other._randomTable != nullptr )
     {
         for ( int i = 0 ; i < TABLE_COLORS ; i++ )
         {
@@ -185,7 +185,7 @@ ColorEntry ColorScheme::colorEntry(int index , uint randomSeed) const
     ColorEntry entry = colorTable()[index];
 
     if ( randomSeed != 0 &&
-        _randomTable != 0 &&
+        _randomTable != nullptr &&
         !_randomTable[index].isNull() )
     {
         const RandomizationRange& range = _randomTable[index];
@@ -213,7 +213,7 @@ void ColorScheme::getColorTable(ColorEntry* table , uint randomSeed) const
 }
 bool ColorScheme::randomizedBackgroundColor() const
 {
-    return _randomTable == 0 ? false : !_randomTable[1].isNull();
+    return _randomTable == nullptr ? false : !_randomTable[1].isNull();
 }
 void ColorScheme::setRandomizedBackgroundColor(bool randomize)
 {
@@ -238,7 +238,7 @@ void ColorScheme::setRandomizationRange( int index , quint16 hue , quint8 satura
     Q_ASSERT( hue <= MAX_HUE );
     Q_ASSERT( index >= 0 && index < TABLE_COLORS );
 
-    if ( _randomTable == 0 )
+    if ( _randomTable == nullptr )
         _randomTable = new RandomizationRange[TABLE_COLORS];
 
     _randomTable[index].hue = hue;
@@ -821,7 +821,7 @@ const ColorScheme* ColorSchemeManager::findColorScheme(const QString& name)
 
         qDebug() << "Could not find color scheme - " << name;
 
-        return 0;
+        return nullptr;
     }
 }
 Q_GLOBAL_STATIC(ColorSchemeManager, theColorSchemeManager)
diff --git a/lib/Emulation.cpp b/lib/Emulation.cpp
index a5cfc71..bd75af3 100644
--- a/lib/Emulation.cpp
+++ b/lib/Emulation.cpp
@@ -51,10 +51,10 @@
 using namespace Konsole;
 
 Emulation::Emulation() :
-  _currentScreen(0),
-  _codec(0),
-  _decoder(0),
-  _keyTranslator(0),
+  _currentScreen(nullptr),
+  _codec(nullptr),
+  _decoder(nullptr),
+  _keyTranslator(nullptr),
   _usesMouse(false),
   _bracketedPasteMode(false)
 {
@@ -398,7 +398,7 @@ bool ExtendedCharTable::extendedCharMatch(ushort hash , ushort* unicodePoints ,
 
     // compare given length with stored sequence length ( given as the first ushort in the
     // stored buffer )
-    if ( entry == 0 || entry[0] != length )
+    if ( entry == nullptr || entry[0] != length )
        return false;
     // if the lengths match, each character must be checked.  the stored buffer starts at
     // entry[1]
@@ -458,7 +458,7 @@ ushort* ExtendedCharTable::lookupExtendedChar(ushort hash , ushort& length) cons
     else
     {
         length = 0;
-        return 0;
+        return nullptr;
     }
 }
 
diff --git a/lib/Filter.cpp b/lib/Filter.cpp
index 0cc5933..f219292 100644
--- a/lib/Filter.cpp
+++ b/lib/Filter.cpp
@@ -98,13 +98,13 @@ Filter::HotSpot* FilterChain::hotSpotAt(int line , int column) const
     {
         Filter* filter = iter.next();
         Filter::HotSpot* spot = filter->hotSpotAt(line,column);
-        if ( spot != 0 )
+        if ( spot != nullptr )
         {
             return spot;
         }
     }
 
-    return 0;
+    return nullptr;
 }
 
 QList<Filter::HotSpot*> FilterChain::hotSpots() const
@@ -121,8 +121,8 @@ QList<Filter::HotSpot*> FilterChain::hotSpots() const
 //QList<Filter::HotSpot*> FilterChain::hotSpotsAtLine(int line) const;
 
 TerminalImageFilterChain::TerminalImageFilterChain()
-: _buffer(0)
-, _linePositions(0)
+: _buffer(nullptr)
+, _linePositions(nullptr)
 {
 }
 
@@ -180,8 +180,8 @@ void TerminalImageFilterChain::setImage(const Character* const image , int lines
 }
 
 Filter::Filter() :
-_linePositions(0),
-_buffer(0)
+_linePositions(nullptr),
+_buffer(nullptr)
 {
 }
 
@@ -275,7 +275,7 @@ Filter::HotSpot* Filter::hotSpotAt(int line , int column) const
         return spot;
     }
 
-    return 0;
+    return nullptr;
 }
 
 Filter::HotSpot::HotSpot(int startLine , int startColumn , int endLine , int endColumn)
diff --git a/lib/History.cpp b/lib/History.cpp
index b297b0e..9cbf498 100644
--- a/lib/History.cpp
+++ b/lib/History.cpp
@@ -89,7 +89,7 @@ FIXME: There is noticeable decrease in speed, also. Perhaps,
 HistoryFile::HistoryFile()
   : ion(-1),
     length(0),
-    fileMap(0)
+    fileMap(nullptr)
 {
   if (tmpFile.open())
   {
@@ -109,15 +109,15 @@ HistoryFile::~HistoryFile()
 //to avoid this.
 void HistoryFile::map()
 {
-    Q_ASSERT( fileMap == 0 );
+    Q_ASSERT( fileMap == nullptr );
 
-    fileMap = (char*)mmap( 0 , length , PROT_READ , MAP_PRIVATE , ion , 0 );
+    fileMap = (char*)mmap( nullptr , length , PROT_READ , MAP_PRIVATE , ion , 0 );
 
     //if mmap'ing fails, fall back to the read-lseek combination
     if ( fileMap == MAP_FAILED )
     {
             readWriteBalance = 0;
-            fileMap = 0;
+            fileMap = nullptr;
             //qDebug() << __FILE__ << __LINE__ << ": mmap'ing history failed.  errno = " << errno;
     }
 }
@@ -127,12 +127,12 @@ void HistoryFile::unmap()
     int result = munmap( fileMap , length );
     Q_ASSERT( result == 0 ); Q_UNUSED( result );
 
-    fileMap = 0;
+    fileMap = nullptr;
 }
 
 bool HistoryFile::isMapped() const
 {
-    return (fileMap != 0);
+    return (fileMap != nullptr);
 }
 
 void HistoryFile::add(const unsigned char* bytes, int len)
@@ -537,7 +537,7 @@ void* CompactHistoryBlock::allocate ( size_t length )
 {
  Q_ASSERT ( length > 0 );
   if ( tail-blockStart+length > blockLength )
-    return NULL;
+    return nullptr;
 
   void* block = tail;
   tail += length;
@@ -628,9 +628,9 @@ CompactHistoryLine::CompactHistoryLine ( const TextLine& line, CompactHistoryBlo
 
     //kDebug() << "number of different formats in string: " << formatLength;
     formatArray = (CharacterFormat*) blockList.allocate(sizeof(CharacterFormat)*formatLength);
-    Q_ASSERT (formatArray!=NULL);
+    Q_ASSERT (formatArray!=nullptr);
     text = (quint16*) blockList.allocate(sizeof(quint16)*line.size());
-    Q_ASSERT (text!=NULL);
+    Q_ASSERT (text!=nullptr);
 
     length=line.size();
     wrapped=false;
@@ -923,7 +923,7 @@ HistoryScroll* HistoryTypeFile::scroll(HistoryScroll *old) const
   HistoryScroll *newScroll = new HistoryScrollFile(m_fileName);
 
   Character line[LINE_SIZE];
-  int lines = (old != 0) ? old->getLines() : 0;
+  int lines = (old != nullptr) ? old->getLines() : 0;
   for(int i = 0; i < lines; i++)
   {
      int size = old->getLineLen(i);
diff --git a/lib/History.h b/lib/History.h
index 16469d0..59da314 100644
--- a/lib/History.h
+++ b/lib/History.h
@@ -293,7 +293,7 @@ public:
 
   CompactHistoryBlock(){
     blockLength = 4096*64; // 256kb
-    head = (quint8*) mmap(0, blockLength, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0);
+    head = (quint8*) mmap(nullptr, blockLength, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANON, -1, 0);
     //head = (quint8*) malloc(blockLength);
     Q_ASSERT(head != MAP_FAILED);
     tail = blockStart = head;
diff --git a/lib/KeyboardTranslator.cpp b/lib/KeyboardTranslator.cpp
index 9d66aa2..32d5287 100644
--- a/lib/KeyboardTranslator.cpp
+++ b/lib/KeyboardTranslator.cpp
@@ -109,7 +109,7 @@ const KeyboardTranslator* KeyboardTranslatorManager::findTranslator(const QStrin
 
     KeyboardTranslator* translator = loadTranslator(name);
 
-    if ( translator != 0 )
+    if ( translator != nullptr )
         _translators[name] = translator;
     else if ( !name.isEmpty() )
         qDebug() << "Unable to load translator" << name;
@@ -155,7 +155,7 @@ KeyboardTranslator* KeyboardTranslatorManager::loadTranslator(const QString& nam
 
     QFile source(path);
     if (name.isEmpty() || !source.open(QIODevice::ReadOnly | QIODevice::Text))
-        return 0;
+        return nullptr;
 
     return loadTranslator(&source,name);
 }
@@ -192,7 +192,7 @@ KeyboardTranslator* KeyboardTranslatorManager::loadTranslator(QIODevice* source,
     else
     {
         delete translator;
-        return 0;
+        return nullptr;
     }
 }
 
diff --git a/lib/Pty.cpp b/lib/Pty.cpp
index 87484be..714101f 100644
--- a/lib/Pty.cpp
+++ b/lib/Pty.cpp
@@ -331,8 +331,8 @@ void Pty::setupChildProcess()
     action.sa_handler = SIG_DFL;
     action.sa_flags = 0;
     for (int signal=1;signal < NSIG; signal++) {
-        sigaction(signal,&action,0L);
+        sigaction(signal,&action,nullptr);
         sigaddset(&sigset, signal);
     }
-    sigprocmask(SIG_UNBLOCK, &sigset, NULL);
+    sigprocmask(SIG_UNBLOCK, &sigset, nullptr);
 }
diff --git a/lib/Pty.h b/lib/Pty.h
index 6c96c3e..f427a53 100644
--- a/lib/Pty.h
+++ b/lib/Pty.h
@@ -70,13 +70,13 @@ Q_OBJECT
      * To start the terminal process, call the run() method with the
      * name of the program to start and appropriate arguments.
      */
-    explicit Pty(QObject* parent = 0);
+    explicit Pty(QObject* parent = nullptr);
 
     /**
      * Construct a process using an open pty master.
      * See KPtyProcess::KPtyProcess()
      */
-    explicit Pty(int ptyMasterFd, QObject* parent = 0);
+    explicit Pty(int ptyMasterFd, QObject* parent = nullptr);
 
     ~Pty() override;
 
diff --git a/lib/Screen.cpp b/lib/Screen.cpp
index ea635e5..cb88fd3 100644
--- a/lib/Screen.cpp
+++ b/lib/Screen.cpp
@@ -1359,7 +1359,7 @@ void Screen::setScroll(const HistoryType& t , bool copyPreviousScroll)
     else
     {
         HistoryScroll* oldScroll = history;
-        history = t.scroll(0);
+        history = t.scroll(nullptr);
         delete oldScroll;
     }
 }
diff --git a/lib/ScreenWindow.cpp b/lib/ScreenWindow.cpp
index 640465f..22e9b08 100644
--- a/lib/ScreenWindow.cpp
+++ b/lib/ScreenWindow.cpp
@@ -30,7 +30,7 @@ using namespace Konsole;
 
 ScreenWindow::ScreenWindow(QObject* parent)
     : QObject(parent)
-    , _windowBuffer(0)
+    , _windowBuffer(nullptr)
     , _windowBufferSize(0)
     , _bufferNeedsUpdate(true)
     , _windowLines(1)
@@ -59,7 +59,7 @@ Character* ScreenWindow::getImage()
 {
     // reallocate internal buffer if the window size has changed
     int size = windowLines() * windowColumns();
-    if (_windowBuffer == 0 || _windowBufferSize != size)
+    if (_windowBuffer == nullptr || _windowBufferSize != size)
     {
         delete[] _windowBuffer;
         _windowBufferSize = size;
diff --git a/lib/ScreenWindow.h b/lib/ScreenWindow.h
index 81d1f97..79613d7 100644
--- a/lib/ScreenWindow.h
+++ b/lib/ScreenWindow.h
@@ -64,7 +64,7 @@ public:
      * to notify the window when the associated screen has changed and synchronize selection updates
      * between all views on a session.
      */
-    ScreenWindow(QObject* parent = 0);
+    ScreenWindow(QObject* parent = nullptr);
     ~ScreenWindow() override;
 
     /** Sets the screen which this window looks onto */
diff --git a/lib/SearchBar.h b/lib/SearchBar.h
index 89d7eb2..0f4299b 100644
--- a/lib/SearchBar.h
+++ b/lib/SearchBar.h
@@ -27,7 +27,7 @@
 class SearchBar : public QWidget {
     Q_OBJECT
 public:
-    SearchBar(QWidget* parent = 0);
+    SearchBar(QWidget* parent = nullptr);
     ~SearchBar() override;
     virtual void show();
     QString searchText();
diff --git a/lib/Session.cpp b/lib/Session.cpp
index 0182f9f..4146459 100644
--- a/lib/Session.cpp
+++ b/lib/Session.cpp
@@ -50,8 +50,8 @@ int Session::lastSessionId = 0;
 
 Session::Session(QObject* parent) :
     QObject(parent),
-        _shellProcess(0)
-        , _emulation(0)
+        _shellProcess(nullptr)
+        , _emulation(nullptr)
         , _monitorActivity(false)
         , _monitorSilence(false)
         , _notifiedActivity(false)
@@ -172,7 +172,7 @@ void Session::addView(TerminalDisplay * widget)
 
     _views.append(widget);
 
-    if ( _emulation != 0 ) {
+    if ( _emulation != nullptr ) {
         // connect emulation - view signals and slots
         connect( widget , SIGNAL(keyPressedSignal(QKeyEvent *)) , _emulation ,
                  SLOT(sendKeyEvent(QKeyEvent *)) );
@@ -220,19 +220,19 @@ void Session::removeView(TerminalDisplay * widget)
 {
     _views.removeAll(widget);
 
-    disconnect(widget,0,this,0);
+    disconnect(widget,nullptr,this,nullptr);
 
-    if ( _emulation != 0 ) {
+    if ( _emulation != nullptr ) {
         // disconnect
         //  - key presses signals from widget
         //  - mouse activity signals from widget
         //  - string sending signals from widget
         //
         //  ... and any other signals connected in addView()
-        disconnect( widget, 0, _emulation, 0);
+        disconnect( widget, nullptr, _emulation, nullptr);
 
         // disconnect state change signals emitted by emulation
-        disconnect( _emulation , 0 , widget , 0);
+        disconnect( _emulation , nullptr , widget , nullptr);
     }
 
     // close the session automatically when the last view is removed
diff --git a/lib/Session.h b/lib/Session.h
index ab63b51..992b9f5 100644
--- a/lib/Session.h
+++ b/lib/Session.h
@@ -71,7 +71,7 @@ public:
      * falls back to using the program specified in the SHELL environment
      * variable.
      */
-    Session(QObject* parent = 0);
+    Session(QObject* parent = nullptr);
     ~Session() override;
 
     /**
diff --git a/lib/TerminalCharacterDecoder.cpp b/lib/TerminalCharacterDecoder.cpp
index 579dedf..92e8293 100644
--- a/lib/TerminalCharacterDecoder.cpp
+++ b/lib/TerminalCharacterDecoder.cpp
@@ -33,7 +33,7 @@
 
 using namespace Konsole;
 PlainTextDecoder::PlainTextDecoder()
- : _output(0)
+ : _output(nullptr)
  , _includeTrailingWhitespace(true)
  , _recordLinePositions(false)
 {
@@ -55,7 +55,7 @@ void PlainTextDecoder::begin(QTextStream* output)
 }
 void PlainTextDecoder::end()
 {
-    _output = 0;
+    _output = nullptr;
 }
 
 void PlainTextDecoder::setRecordLinePositions(bool record)
@@ -109,7 +109,7 @@ void PlainTextDecoder::decodeLine(const Character* const characters, int count,
 }
 
 HTMLDecoder::HTMLDecoder() :
-        _output(0)
+        _output(nullptr)
     ,_colorTable(base_color_table)
        ,_innerSpanOpen(false)
        ,_lastRendition(DEFAULT_RENDITION)
@@ -139,7 +139,7 @@ void HTMLDecoder::end()
 
     *_output << QString::fromStdWString(text);
 
-    _output = 0;
+    _output = nullptr;
 
 }
 
diff --git a/lib/TerminalDisplay.cpp b/lib/TerminalDisplay.cpp
index 35f6b4b..b666a28 100644
--- a/lib/TerminalDisplay.cpp
+++ b/lib/TerminalDisplay.cpp
@@ -128,7 +128,7 @@ void TerminalDisplay::setScreenWindow(ScreenWindow* window)
     // disconnect existing screen window if any
     if ( _screenWindow )
     {
-        disconnect( _screenWindow , 0 , this , 0 );
+        disconnect( _screenWindow , nullptr , this , nullptr );
     }
 
     _screenWindow = window;
@@ -312,9 +312,9 @@ void TerminalDisplay::setFont(const QFont &)
 
 TerminalDisplay::TerminalDisplay(QWidget *parent)
 :QWidget(parent)
-,_screenWindow(0)
+,_screenWindow(nullptr)
 ,_allowBell(true)
-,_gridLayout(0)
+,_gridLayout(nullptr)
 ,_fontHeight(1)
 ,_fontWidth(1)
 ,_fontAscent(1)
@@ -325,7 +325,7 @@ TerminalDisplay::TerminalDisplay(QWidget *parent)
 ,_usedColumns(1)
 ,_contentHeight(1)
 ,_contentWidth(1)
-,_image(0)
+,_image(nullptr)
 ,_randomSeed(0)
 ,_resizing(false)
 ,_terminalSizeHint(false)
@@ -349,10 +349,10 @@ TerminalDisplay::TerminalDisplay(QWidget *parent)
 ,_tripleClickMode(SelectWholeLine)
 ,_isFixedSize(false)
 ,_possibleTripleClick(false)
-,_resizeWidget(0)
-,_resizeTimer(0)
+,_resizeWidget(nullptr)
+,_resizeTimer(nullptr)
 ,_flowControlWarningEnabled(false)
-,_outputSuspendedLabel(0)
+,_outputSuspendedLabel(nullptr)
 ,_lineSpacing(0)
 ,_colorsInverted(false)
 ,_blendColor(qRgba(0,0,0,0xff))
@@ -941,7 +941,7 @@ void TerminalDisplay::scrollImage(int lines , const QRect& screenWindowRegion)
 
     // return if there is nothing to do
     if (    lines == 0
-         || _image == 0
+         || _image == nullptr
          || !region.isValid()
          || (region.top() + abs(lines)) >= region.bottom()
          || this->_lines <= region.height() ) return;
diff --git a/lib/TerminalDisplay.h b/lib/TerminalDisplay.h
index fb55a58..5105382 100644
--- a/lib/TerminalDisplay.h
+++ b/lib/TerminalDisplay.h
@@ -82,7 +82,7 @@ class KONSOLEPRIVATE_EXPORT TerminalDisplay : public QWidget
 
 public:
     /** Constructs a new terminal display widget with the specified parent. */
-    TerminalDisplay(QWidget *parent=0);
+    TerminalDisplay(QWidget *parent=nullptr);
     ~TerminalDisplay() override;
 
     /** Returns the terminal color palette used by the display. */
diff --git a/lib/Vt102Emulation.cpp b/lib/Vt102Emulation.cpp
index cf677c2..622550e 100644
--- a/lib/Vt102Emulation.cpp
+++ b/lib/Vt102Emulation.cpp
@@ -1341,8 +1341,8 @@ char Vt102Emulation::eraseChar() const
 {
   KeyboardTranslator::Entry entry = _keyTranslator->findEntry(
                                             Qt::Key_Backspace,
-                                            0,
-                                            0);
+                                            nullptr,
+                                            nullptr);
   if ( entry.text().count() > 0 )
       return entry.text().at(0);
   else
diff --git a/lib/kprocess.h b/lib/kprocess.h
index 386f870..9fbfb4e 100644
--- a/lib/kprocess.h
+++ b/lib/kprocess.h
@@ -77,7 +77,7 @@ public:
     /**
      * Constructor
      */
-    explicit KProcess(QObject *parent = 0);
+    explicit KProcess(QObject *parent = nullptr);
 
     /**
      * Destructor
diff --git a/lib/kpty.cpp b/lib/kpty.cpp
index b42bf95..2b70dd2 100644
--- a/lib/kpty.cpp
+++ b/lib/kpty.cpp
@@ -544,7 +544,7 @@ void KPty::login(const char * user, const char * remotehost)
 # ifdef HAVE_UTMPX
     gettimeofday(&l_struct.ut_tv, 0);
 # else
-    l_struct.ut_time = time(0);
+    l_struct.ut_time = time(nullptr);
 # endif
 
 # ifdef HAVE_LOGIN
@@ -646,7 +646,7 @@ void KPty::logout()
     }
     endutxent();
 #  else
-    ut->ut_time = time(0);
+    ut->ut_time = time(nullptr);
     pututline(ut);
 }
 endutent();
diff --git a/lib/kpty.h b/lib/kpty.h
index ab34f6e..6415512 100644
--- a/lib/kpty.h
+++ b/lib/kpty.h
@@ -95,7 +95,7 @@ public:
      *  of the client. For local logins from inside an X session it should
      *  be the name of the X display. Otherwise it should be empty.
      */
-    void login(const char * user = 0, const char * remotehost = 0);
+    void login(const char * user = nullptr, const char * remotehost = nullptr);
 
     /**
      * Removes the utmp entry for this tty.
diff --git a/lib/kptydevice.cpp b/lib/kptydevice.cpp
index 90b4a58..983d4ea 100644
--- a/lib/kptydevice.cpp
+++ b/lib/kptydevice.cpp
@@ -74,7 +74,7 @@ static void qt_ignore_sigpipe()
         struct sigaction noaction;
         memset(&noaction, 0, sizeof(noaction));
         noaction.sa_handler = SIG_IGN;
-        sigaction(SIGPIPE, &noaction, 0);
+        sigaction(SIGPIPE, &noaction, nullptr);
     }
 }
 
@@ -211,7 +211,7 @@ bool KPtyDevicePrivate::doWait(int msecs, bool reading)
     struct timeval tv, *tvp;
 
     if (msecs < 0)
-        tvp = 0;
+        tvp = nullptr;
     else {
         tv.tv_sec = msecs / 1000;
         tv.tv_usec = (msecs % 1000) * 1000;
@@ -243,7 +243,7 @@ bool KPtyDevicePrivate::doWait(int msecs, bool reading)
         }
 #endif
 
-        switch (select(q->masterFd() + 1, &rfds, &wfds, 0, tvp)) {
+        switch (select(q->masterFd() + 1, &rfds, &wfds, nullptr, tvp)) {
         case -1:
             if (errno == EINTR)
                 break;
diff --git a/lib/kptydevice.h b/lib/kptydevice.h
index 8b23bce..a379af1 100644
--- a/lib/kptydevice.h
+++ b/lib/kptydevice.h
@@ -55,7 +55,7 @@ public:
     /**
      * Constructor
      */
-    KPtyDevice(QObject *parent = 0);
+    KPtyDevice(QObject *parent = nullptr);
 
     /**
      * Destructor:
@@ -339,7 +339,7 @@ struct KPtyDevicePrivate : public KPtyPrivate {
     KPtyDevicePrivate(KPty* parent) :
         KPtyPrivate(parent),
         emittedReadyRead(false), emittedBytesWritten(false),
-        readNotifier(0), writeNotifier(0)
+        readNotifier(nullptr), writeNotifier(nullptr)
     {
     }
 
diff --git a/lib/kptyprocess.h b/lib/kptyprocess.h
index 9172062..0d3a04a 100644
--- a/lib/kptyprocess.h
+++ b/lib/kptyprocess.h
@@ -74,7 +74,7 @@ public:
     /**
      * Constructor
      */
-    explicit KPtyProcess(QObject *parent = 0);
+    explicit KPtyProcess(QObject *parent = nullptr);
 
     /**
      * Construct a process using an open pty master.
@@ -83,7 +83,7 @@ public:
      *   The process does not take ownership of the descriptor;
      *   it will not be automatically closed at any point.
      */
-    KPtyProcess(int ptyMasterFd, QObject *parent = 0);
+    KPtyProcess(int ptyMasterFd, QObject *parent = nullptr);
 
     /**
      * Destructor
diff --git a/lib/qtermwidget.cpp b/lib/qtermwidget.cpp
index 4a5172a..165b431 100644
--- a/lib/qtermwidget.cpp
+++ b/lib/qtermwidget.cpp
@@ -50,7 +50,7 @@ void *createTermWidget(int startnow, void *parent)
 }
 
 struct TermWidgetImpl {
-    TermWidgetImpl(QWidget* parent = 0);
+    TermWidgetImpl(QWidget* parent = nullptr);
 
     TerminalDisplay *m_terminalDisplay;
     Session *m_session;
@@ -425,7 +425,7 @@ void QTermWidget::setTextCodec(QTextCodec *codec)
 
 void QTermWidget::setColorScheme(const QString& origName)
 {
-    const ColorScheme *cs = 0;
+    const ColorScheme *cs = nullptr;
 
     const bool isFile = QFile::exists(origName);
     const QString& name = isFile ?
diff --git a/lib/qtermwidget.h b/lib/qtermwidget.h
index 142cb4a..ea0e828 100644
--- a/lib/qtermwidget.h
+++ b/lib/qtermwidget.h
@@ -51,9 +51,9 @@ public:
 
     //Creation of widget
     QTermWidget(int startnow, // 1 = start shell programm immediatelly
-                QWidget * parent = 0);
+                QWidget * parent = nullptr);
     // A dummy constructor for Qt Designer. startnow is 1 by default
-    QTermWidget(QWidget *parent = 0);
+    QTermWidget(QWidget *parent = nullptr);
 
     ~QTermWidget() override;