[boost] RE: Boost.Threads: RW mutexes and locks.

From: Batov, Vladimir (Vladimir.Batov_at_[hidden])
Date: 2004-06-28 00:21:55

John Torjo wrote:

> Batov, Vladimir wrote:
>>  
>>  class writer_lock : public boost::mutex::scoped_lock
>>  {
>>      typedef boost::mutex::scoped_lock super;
>>  
>>      public:
>>  
>>      writer_lock(rw_mutex& mutex) : super(mutex.mutex_),
mutex_(mutex)
>>      {
>>          ++mutex_.num_writers_; // Make new readers wait.
>           ^^^^
>
> just curios, shouldn't this be thread-safe?

I believe it is thread-safe as writer_lock currently inherits from
scoped_lock and, consequently, we get inside the writer_lock constructor
after its base-class scoped_lock constructor. The base-class constructor
does the synchronization.