Throwing exceptions from constructors

If you do throw an exception from a constructor, keep in mind that you need to use the function try/catch syntax if you need to catch that exception in a constructor initializer list.

e.g.

func::func() : foo()
{
    try {...}
    catch (...) // will NOT catch exceptions thrown from foo constructor
    { ... }
}

vs.

func::func()
    try : foo() {...}
    catch (...) // will catch exceptions thrown from foo constructor
    { ... }

Yes, throwing an exception from the failed constructor is the standard way of doing this. Read this FAQ about Handling a constructor that fails for more information. Having a init() method will also work, but everybody who creates the object of mutex has to remember that init() has to be called. I feel it goes against the RAII principle.