Christian Wieninger wrote:
Thanks! So the following should work (please correct me if I'm wrong):
I add a cMutex object in the cList derived class and 2 functions:

class cThreadSafecList: public cList<...> {
   cMutex mutex;
   void Lock(void) { mutex.Lock(); }
   void Unlock(void) { mutex.Unlock(); }

Its easier and more convenient if you simply do this:

  class cThreadSafeList: public cList<...>, public cMutex {

This allows you to use the very comfortable cMutexLock:

void myfunction() {
  cMutexLock MyLock(MyThreadsafeList);

  // do critical stuff

  // unlock will be called auto-magically here

The locking time should be short to avoid a sluggish OSD, if one accesses MyThreadSafecList in the main thread.

Don't lock too often, doing all the unlocking and re-locking may eat up more time than simply holding the lock for a moment. Only unlock if you don't need access for quite some time.

btw: A mutex lock is always assigned to a whole thread. Its safe to lock the mutex several times from one thread. You can guard critical function calls with a lock, and place another lock at the beginning of larger functions to group all the small locks into one big.

btw2: Each cThread has a built-in mutex for free use. So if it matches your situation, do this:

  class cListWithThread: public cList<...>, public cThread {

Instead of cMutexLock, you can use cThreadLock here.



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