add command line option to skip the version check at startup

--noversioncheck or -V are recognized

src/app/main.cpp

@@ -119,6 +119,7 @@ void usage( std::string const & appName )
             << "\t[--project projectfile]\tload the given QGIS project\n"
             << "\t[--extent xmin,ymin,xmax,ymax]\tset initial map extent\n"
             << "\t[--nologo]\thide splash screen\n"
+            << "\t[--noversioncheck]\tdon't check for new version of QGIS at startup"
             << "\t[--noplugins]\tdon't restore plugins on startup\n"
             << "\t[--nocustomization]\tdon't apply GUI customization\n"
             << "\t[--customizationfile]\tuse the given ini file as GUI customization\n"
@@ -476,6 +477,7 @@ int main( int argc, char *argv[] )
   int mySnapshotHeight = 600;
 
   bool myHideSplash = false;
+  bool mySkipVersionCheck = false;
 #if defined(ANDROID)
   QgsDebugMsg( QString( "Android: Splash hidden" ) );
   myHideSplash = true;
@@ -543,6 +545,10 @@ int main( int argc, char *argv[] )
       {
         myHideSplash = true;
       }
+      else if ( arg == "--noversioncheck" || arg == "-V" )
+      {
+        mySkipVersionCheck = true;
+      }
       else if ( arg == "--noplugins" || arg == "-P" )
       {
         myRestorePlugins = false;
@@ -1032,7 +1038,7 @@ int main( int argc, char *argv[] )
   // this should be done in QgsApplication::init() but it doesn't know the settings dir.
   QgsApplication::setMaxThreads( QSettings().value( "/qgis/max_threads", -1 ).toInt() );
 
-  QgisApp *qgis = new QgisApp( mypSplash, myRestorePlugins ); // "QgisApp" used to find canonical instance
+  QgisApp *qgis = new QgisApp( mypSplash, myRestorePlugins, mySkipVersionCheck ); // "QgisApp" used to find canonical instance
   qgis->setObjectName( "QgisApp" );
 
   myApp.connect(

src/app/qgisapp.cpp

@@ -531,7 +531,7 @@ static bool cmpByText_( QAction* a, QAction* b )
 QgisApp *QgisApp::smInstance = nullptr;
 
 // constructor starts here
-QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, QWidget * parent, Qt::WindowFlags fl )
+QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, bool skipVersionCheck, QWidget * parent, Qt::WindowFlags fl )
     : QMainWindow( parent, fl )
     , mNonEditMapTool( nullptr )
     , mScaleLabel( nullptr )
@@ -639,7 +639,7 @@ QgisApp::QgisApp( QSplashScreen *splash, bool restorePlugins, QWidget * parent,
   // what type of project to auto-open
   mProjOpen = settings.value( "/qgis/projOpenAtLaunch", 0 ).toInt();
 
-  mWelcomePage = new QgsWelcomePage;
+  mWelcomePage = new QgsWelcomePage( skipVersionCheck );
 
   mCentralContainer = new QStackedWidget;
   mCentralContainer->insertWidget( 0, mMapCanvas );

src/app/qgisapp.h

@@ -134,7 +134,7 @@ class APP_EXPORT QgisApp : public QMainWindow, private Ui::MainWindow
     Q_OBJECT
   public:
     //! Constructor
-    QgisApp( QSplashScreen *splash, bool restorePlugins = true, QWidget *parent = nullptr, Qt::WindowFlags fl = Qt::Window );
+    QgisApp( QSplashScreen *splash, bool restorePlugins = true, bool skipVersionCheck = false, QWidget *parent = nullptr, Qt::WindowFlags fl = Qt::Window );
     //! Constructor for unit tests
     QgisApp();
     //! Destructor

src/app/qgswelcomepage.cpp

@@ -24,7 +24,7 @@
 #include <QListView>
 #include <QSettings>
 
-QgsWelcomePage::QgsWelcomePage( QWidget* parent )
+QgsWelcomePage::QgsWelcomePage( bool skipVersionCheck, QWidget* parent )
     : QWidget( parent )
 {
   QSettings settings;
@@ -60,7 +60,7 @@ QgsWelcomePage::QgsWelcomePage( QWidget* parent )
   mVersionInformation->setVisible( false );
 
   mVersionInfo = new QgsVersionInfo();
-  if ( !QgsApplication::isRunningFromBuildDir() && settings.value( "/qgis/checkVersion", true ).toBool() )
+  if ( !QgsApplication::isRunningFromBuildDir() && settings.value( "/qgis/checkVersion", true ).toBool() && !skipVersionCheck )
   {
     connect( mVersionInfo, SIGNAL( versionInfoAvailable() ), this, SLOT( versionInfoReceived() ) );
     mVersionInfo->checkVersion();

src/app/qgswelcomepage.h

@@ -28,7 +28,7 @@ class QgsWelcomePage : public QWidget
     Q_OBJECT
 
   public:
-    explicit QgsWelcomePage( QWidget* parent = nullptr );
+    explicit QgsWelcomePage( bool skipVersionCheck = false, QWidget* parent = nullptr );
 
     ~QgsWelcomePage();