diff --git a/c-host/app.c b/c-host/app.c
index f14c783d..5b54d749 100644
--- a/c-host/app.c
+++ b/c-host/app.c
@@ -24,6 +24,7 @@ Place, Suite 330, Boston, MA 02111-1307 USA
 #include <unistd.h>
 #include <stdlib.h>
 #include "debug.h"
+#include "locking.h"
 #include "capture/interfaces.h"
 #include "KVMFR.h"
 
@@ -81,7 +82,9 @@ static int frameThread(void * opaque)
 {
   DEBUG_INFO("Frame thread started");
 
-  int frameIndex = 0;
+  int      frameIndex = 0;
+  volatile KVMFRFrame * fi = &(app.shmHeader->frame);
+
   while(app.running)
   {
     if (!os_waitEvent(app.frameEvent) || !app.running)
@@ -93,6 +96,32 @@ static int frameThread(void * opaque)
       DEBUG_ERROR("Failed to get the frame");
     os_signalEvent(app.updateEvent);
 
+    // wait for the client to finish with the previous frame
+    while(fi->flags & KVMFR_FRAME_FLAG_UPDATE)
+    {
+      // this generally never happens
+      usleep(1000);
+    }
+
+    switch(frame.format)
+    {
+      case CAPTURE_FMT_BGRA  : fi->type = FRAME_TYPE_BGRA  ; break;
+      case CAPTURE_FMT_RGBA  : fi->type = FRAME_TYPE_RGBA  ; break;
+      case CAPTURE_FMT_RGBA10: fi->type = FRAME_TYPE_RGBA10; break;
+      case CAPTURE_FMT_YUV420: fi->type = FRAME_TYPE_YUV420; break;
+      default:
+        DEBUG_ERROR("Unsupported frame format %d, skipping frame", frame.format);
+        continue;
+    }
+
+    fi->width   = frame.width;
+    fi->height  = frame.height;
+    fi->stride  = frame.stride;
+    fi->pitch   = frame.pitch;
+    fi->dataPos = app.frameOffset[frameIndex];
+
+    INTERLOCKED_OR8(&fi->flags, KVMFR_FRAME_FLAG_UPDATE);
+
     if (++frameIndex == MAX_FRAMES)
       frameIndex = 0;
   }
@@ -174,9 +203,9 @@ int app_main()
   DEBUG_INFO("IVSHMEM Address  : 0x%" PRIXPTR, (uintptr_t)shmemMap);
 
   app.shmHeader        = (KVMFRHeader *)shmemMap;
-  app.pointerData       = (uint8_t *)ALIGN_UP(shmemMap + sizeof(KVMFRHeader));
-  app.pointerDataSize   = 1048576; // 1MB fixed for pointer size, should be more then enough
-  app.pointerOffset     = app.pointerData - shmemMap;
+  app.pointerData      = (uint8_t *)ALIGN_UP(shmemMap + sizeof(KVMFRHeader));
+  app.pointerDataSize  = 1048576; // 1MB fixed for pointer size, should be more then enough
+  app.pointerOffset    = app.pointerData - shmemMap;
   app.frames           = (uint8_t *)ALIGN_UP(app.pointerData + app.pointerDataSize);
   app.frameSize        = ALIGN_DN((shmemSize - (app.frames - shmemMap)) / MAX_FRAMES);
 
@@ -242,6 +271,15 @@ int app_main()
     goto exit;
   }
 
+  // initialize the shared memory headers
+  memcpy(app.shmHeader->magic, KVMFR_HEADER_MAGIC, sizeof(KVMFR_HEADER_MAGIC));
+  app.shmHeader->version = KVMFR_HEADER_VERSION;
+
+  // zero and notify the client we are starting
+  memset(&(app.shmHeader->frame ), 0, sizeof(KVMFRFrame ));
+  memset(&(app.shmHeader->cursor), 0, sizeof(KVMFRCursor));
+  app.shmHeader->flags &= ~KVMFR_HEADER_FLAG_RESTART;
+
   if (!captureStart())
   {
     exitcode = -1;
@@ -251,8 +289,12 @@ int app_main()
   // start signalled
   os_signalEvent(app.updateEvent);
 
+  volatile char * flags = (volatile char *)&(app.shmHeader->flags);
+
   while(app.running)
   {
+    INTERLOCKED_AND8(flags, ~(KVMFR_HEADER_FLAG_RESTART));
+
     // wait for one of the threads to flag an update
     if (!os_waitEvent(app.updateEvent) || !app.running)
       break;
diff --git a/c-host/capture/interface.h b/c-host/capture/interface.h
index b8b8f0df..a9b89669 100644
--- a/c-host/capture/interface.h
+++ b/c-host/capture/interface.h
@@ -46,6 +46,7 @@ typedef struct CaptureFrame
   unsigned int   width;
   unsigned int   height;
   unsigned int   pitch;
+  unsigned int   stride;
   CaptureFormat  format;
   void         * data;
 }
diff --git a/c-host/linux/capture/xcb.c b/c-host/linux/capture/xcb.c
index eea90a40..866e2ad0 100644
--- a/c-host/linux/capture/xcb.c
+++ b/c-host/linux/capture/xcb.c
@@ -203,6 +203,7 @@ static bool xcb_getFrame(CaptureFrame * frame)
   frame->width  = this->width;
   frame->height = this->height;
   frame->pitch  = this->width * 4;
+  frame->stride = this->width;
   frame->format = CAPTURE_FMT_BGRA;
   memcpy(frame->data, this->data, this->width * this->height * 4);
 
diff --git a/c-host/windows/capture/dxgi.c b/c-host/windows/capture/dxgi.c
index 6b2fc91d..0636ba59 100644
--- a/c-host/windows/capture/dxgi.c
+++ b/c-host/windows/capture/dxgi.c
@@ -469,6 +469,7 @@ static bool dxgi_getFrame(CaptureFrame * frame)
   frame->width  = this->width;
   frame->height = this->height;
   frame->pitch  = this->pitch;
+  frame->stride = this->stride;
   frame->format = this->format;
 
   HRESULT status;
diff --git a/common/locking.h b/common/locking.h
new file mode 100644
index 00000000..97ed72ba
--- /dev/null
+++ b/common/locking.h
@@ -0,0 +1,27 @@
+/*
+Looking Glass - KVM FrameRelay (KVMFR) Client
+Copyright (C) 2017-2019 Geoffrey McRae <geoff@hostfission.com>
+https://looking-glass.hostfission.com
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; either version 2 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+#pragma once
+
+#if __MINGW32__
+#define INTERLOCKED_AND8 __sync_and_and_fetch
+#define INTERLOCKED_OR8 __sync_or_and_fetch
+#else
+#define INTERLOCKED_OR8 InterlockedOr8
+#define INTERLOCKED_AND8 InterlockedAnd8
+#endif
\ No newline at end of file