Wait for objc block

[lukaskollmer]

I want to wait for an async objc block to finish before returning from a JavaScript function. The problem is that the node process exists before the block is called by Cocoa. How can I wait for the block and make sure node doesn't exit until after the block was called?

I know that in Objective-C, I can use a dispatch_semaphore_t, but I couldn't get that working via NodObjC.

Any ideas?