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;
}
```