Re: thread-safe new and delete

On Oct 29, 7:12 pm, mpho <tjab...@gmail.com> wrote:


I am assuming this question is about guarding a 'new-ed' pointer in a
multi-threading application. If that is the case, the best thing would
be to guard the code section accessing or modifiying the pointer using
a mutex object. Also, whichever thread attempts to delete it should
set the pointer to NULL after deletion, and also check for a NULL
value on the pointer before attempting to delete it.

Sample Pseudo Code-

// lets say MyClass* p_obj is the shared pointer among the threads
Thread1
.......
.......
Guard(myMutex)
{
  //allocate memory
  p_obj = new MyClass();

}
.......
.......

//Thread2

Guard(myMutex)
{
   if(p_obj != NULL)
   {
       delete p_obj;
       p_obj = NULL;
   }

}

Make sure you dont create copies of p_obj to avoid danging pointers.
You could use smart pointers, if you really need to have copies.

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