// page04.html,v 1.9 1999/09/22 03:13:45 jcej Exp #ifndef TASK_H #define TASK_H #include "ace/Task.h" #if !defined (ACE_LACKS_PRAGMA_ONCE) # pragma once #endif /* ACE_LACKS_PRAGMA_ONCE */ /* Like the thread-pool server tutorial, we'll derive from ACE_Task<>. Our goal here is to show off the ACE_Message_Queue and the best way to do that is to use one to pass data between threads. The easiest way to create threads is with ACE_Task<> */ class Task : public ACE_Task <ACE_MT_SYNCH> { public: typedef ACE_Task <ACE_MT_SYNCH> inherited; /* The constructor/destructor are simple but take care of some necessary housekeeping. */ Task (size_t n_threads); ~Task (void); /* open() will kick off our thread pool for us. */ int open (void * = 0); /* Our worker method */ int svc (void); /* All we'll do here is print a message to the user. */ int close (u_long flags = 0); protected: /* Just to be clever, I'll use an ACE_Barrier to cause the threads to sync in svc() before doing any real work. */ ACE_Barrier barrier_; size_t n_threads_; // Number of threads in the pool. }; #endif /* TASK_H */
The only thing here that we didn't see in the thread-pool server is the ACE_Barrier. The application logic really doesn't need it but it is a handy way to synchronize the threads at the beginning of svc(). In testing I found that if I didn't sync svc(), the first thread to get activated would tend to get all of the messages before the other threads came alive.