RAII

[Arun Chandrasekaran via Digitalmars-d-learn]

I'm trying to write an RAII wrapper on Linux.

I understand struct in D doesn't have default constructor (for 
.init reasons).
I don't want to use `scope`.

Is there an elegant way to achieve this in D?

```
import core.sys.posix.pthread;
import core.sys.posix.sys.types;

/// Makes pthread_mutexattr_t cleanup easy when using exceptions
struct mutexattr_wrapper
{
     /// Constructor
     this(bool _)
     {
         if (pthread_mutexattr_init(&m_attr) != 0 ||
             pthread_mutexattr_setpshared(&m_attr, 
PTHREAD_PROCESS_SHARED)!= 0)
           // may be I will add few more methods here
           throw custom_exception("pthread_mutexattr_xxxx failed");
     }

     /// Destructor
     ~this() {  pthread_mutexattr_destroy(&m_attr);  }

     /// This allows using mutexattr_wrapper as pthread_mutexattr_t
     alias m_attr this;

     pthread_mutexattr_t m_attr;
}
```