The documentation for NSFileManager contains this curious statement:
> In Mac OS X v 10.5 and later you should consider using [[NSFileManager alloc]
> init] rather than the singleton methoddefaultManager. Instances of
> NSFileManager are considered thread-safe when created using [[NSFileManager
> alloc] init].
This makes me wonder:
1. Why are the additional instances only "considered" thread-safe. Doesn't
anyone know?
2. What does "thread-safe" mean in this context? I would take it to mean that
*any* single instance allocated with [[NSFileManager alloc] init] can be used
by *any* thread. Or does it mean that each thread needs a unique instance, but
such instances happily co-exist?
3. If any single instance allocated with [[NSFileManager alloc] init] is
thread-safe in the fullest sense, why doesn't [NSFileManager defaultManger]
just return one of these, so that it can be (considered) thread-safe too?
The Leopard release notes don't shed much light.
I did find this thread from 2008:
http://www.omnigroup.com/mailman/archive/macosx-dev/2008-June/061392.html
which appears to say the documentation is wrong. It appears to say that
instances are not thread-safe, but can safely be used by one thread at a time.
I also found this in the Threaded Programming Guide:
> Thread-Safe Classes
>
> The following classes and functions are generally considered to be
> thread-safe. You can use the same instance from multiple threads without
> first acquiring a lock.
>
> [...]
> • NSFileManager (in Mac OS X v10.5 and later)
which contradicts that thread.
Anyone in the know got confirmation/answers on this? (I only care about 10.5
and later.)
_______________________________________________
Cocoa-dev mailing list ([email protected])
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com
This email sent to [email protected]
