diff --git a/mac.c b/mac.c
index 94ef5d2..ff37f01 100644
--- a/mac.c
+++ b/mac.c
@@ -266,6 +266,8 @@ PtrAddEvent(buttonMask, x, y, cl)
                      (buttonMask & (1 << 7)) ? TRUE : FALSE);
 }
 
+Bool viewOnly = FALSE, sharedMode = FALSE;
+
 void 
 ScreenInit(int argc, char**argv)
 {
@@ -278,8 +280,15 @@ ScreenInit(int argc, char**argv)
   rfbScreen->paddedWidthInBytes = CGDisplayBytesPerRow(kCGDirectMainDisplay);
   rfbScreen->frameBuffer =
     (char *)CGDisplayBaseAddress(kCGDirectMainDisplay);
-  rfbScreen->ptrAddEvent = PtrAddEvent;
-  rfbScreen->kbdAddEvent = KbdAddEvent;
+
+  if(!viewOnly) {
+    rfbScreen->ptrAddEvent = PtrAddEvent;
+    rfbScreen->kbdAddEvent = KbdAddEvent;
+  }
+  if(sharedMode) {
+    rfbScreen->rfbAlwaysShared = TRUE;
+  }
+
   rfbInitServer(rfbScreen);
 }
 
@@ -321,6 +330,10 @@ int main(int argc,char *argv[])
       startTime = time(0);
     } else if(strcmp(argv[i],"-runforever")==0) {
       disconnectAfterFirstClient = FALSE;
+    } else if(strcmp(argv[i],"-viewonly")==0) {
+      viewOnly=TRUE;
+    } else if(strcmp(argv[i],"-shared")==0) {
+      sharedMode=TRUE;
     }
 
   ScreenInit(argc,argv);
diff --git a/x11vnc.c b/x11vnc.c
index 70b4ca8..3c067f1 100644
--- a/x11vnc.c
+++ b/x11vnc.c
@@ -16,8 +16,10 @@
 Display *dpy = 0;
 int window;
 int c=0,blockLength = 32;
-int tileX=0,tileY=0,tileWidth=32,tileHeight=32*2,dontTile=True;
+int tileX=0,tileY=0,tileWidth=32,tileHeight=32*2,dontTile=TRUE;
 Bool gotInput = FALSE;
+Bool viewOnly = FALSE;
+Bool sharedMode = FALSE;
 
 Bool disconnectAfterFirstClient = TRUE;
 
@@ -129,7 +131,7 @@ int oldButtonMask = 0;
 void mouse(int buttonMask,int x,int y,rfbClientPtr cl)
 {
   int i=0;
-  //fprintf(stderr,"/");
+
   XTestFakeMotionEvent(dpy,0,x,y,CurrentTime );
   while(i<5) {
     if ((oldButtonMask&(1<<i))!=(buttonMask&(1<<i)))
@@ -299,7 +301,11 @@ int main(int argc,char** argv)
     } else if(strcmp(argv[i],"-runforever")==0) {
       disconnectAfterFirstClient = FALSE;
     } else if(strcmp(argv[i],"-tile")==0) {
-      dontTile=False;
+      dontTile=FALSE;
+    } else if(strcmp(argv[i],"-viewonly")==0) {
+      viewOnly=TRUE;
+    } else if(strcmp(argv[i],"-shared")==0) {
+      sharedMode=TRUE;
     }
 
   updateCounter = dontTile?20:1;
@@ -380,8 +386,14 @@ int main(int argc,char** argv)
   screen->frameBuffer = backupImage;
   screen->cursor = 0;
   screen->newClientHook = newClient;
-  screen->kbdAddEvent = keyboard;
-  screen->ptrAddEvent = mouse;
+
+  if(!viewOnly) {
+    screen->kbdAddEvent = keyboard;
+    screen->ptrAddEvent = mouse;
+  }
+  if(sharedMode) {
+    screen->rfbAlwaysShared = TRUE;
+  }
 
   screen->rfbDeferUpdateTime = 1;
   updateCounter /= screen->rfbDeferUpdateTime;