return value of rfbProcessEvents tells if an update was pending

libvncserver/main.c

@@ -791,12 +791,13 @@ void gettimeofday(struct timeval* tv,char* dummy)
 /* defined in rfbserver.c, but kind of "private" */
 rfbClientPtr rfbClientIteratorHead(rfbClientIteratorPtr i);
 
-void
+rfbBool
 rfbProcessEvents(rfbScreenInfoPtr screen,long usec)
 {
   rfbClientIteratorPtr i;
   rfbClientPtr cl,clPrev;
   struct timeval tv;
+  rfbBool result=FALSE;
 
   if(usec<0)
     usec=screen->deferUpdateTime*1000;
@@ -812,6 +813,7 @@ rfbProcessEvents(rfbScreenInfoPtr screen,long usec)
   while(cl) {
     if (cl->sock >= 0 && !cl->onHold && FB_UPDATE_PENDING(cl) &&
         !sraRgnEmpty(cl->requestedRegion)) {
+      result=TRUE;
       if(screen->deferUpdateTime == 0) {
 	  rfbSendFramebufferUpdate(cl,cl->modifiedRegion);
       } else if(cl->startDeferring.tv_usec == 0) {
@@ -831,10 +833,14 @@ rfbProcessEvents(rfbScreenInfoPtr screen,long usec)
     }
     clPrev=cl;
     cl=rfbClientIteratorNext(i);
-    if(clPrev->sock==-1)
+    if(clPrev->sock==-1) {
       rfbClientConnectionGone(clPrev);
+      result=TRUE;
+    }
   }
   rfbReleaseClientIterator(i);
+
+  return result;
 }
 
 void rfbRunEventLoop(rfbScreenInfoPtr screen, long usec, rfbBool runInBackground)

rfb/rfb.h

@@ -789,10 +789,11 @@ extern void rfbRefuseOnHoldClient(rfbClientPtr cl);
 /* call one of these two functions to service the vnc clients.
  usec are the microseconds the select on the fds waits.
  if you are using the event loop, set this to some value > 0, so the
- server doesn't get a high load just by listening. */
+ server doesn't get a high load just by listening.
+ rfbProcessEvents() returns TRUE if an update was pending. */
 
 extern void rfbRunEventLoop(rfbScreenInfoPtr screenInfo, long usec, rfbBool runInBackground);
-extern void rfbProcessEvents(rfbScreenInfoPtr screenInfo,long usec);
+extern rfbBool rfbProcessEvents(rfbScreenInfoPtr screenInfo,long usec);
 
 #endif