Nsoutputstream write asynchronous
Note: I've moved the logic below into the completion handler see the code above and I no longer see any error. I've done both in the past and am in the midst of testing for best performance.
Ios swift write text to file
I am still trying to grasp the patterns that are involved with this. It is included for completeness. Thank you for providing feedback! So when dealing with large files one is at the mercy of whatever internal mechanism is at work within the NSData methods. When there is no more data to write, dispose of the stream object. Atomic writes guarantee that the data is either saved in its entirety, or it fails completely. Please try submitting your feedback later. However, this causes some problems. The Core Foundation stream types sets the client termed a context in Core Foundation differently than the NSStream sets the delegate; calls to set the delegate should not be mixed with calls to set the context. If this write succeeds, then the method moves the temporary file to its final location. Next Previous Cocoa Streams Streams provide an easy way for a program to exchange data with a variety of media in a device-independent way. I could add an NSLock, protecting the writeData method with it, and I believe that would solve the issue in that place.
You can also use patterns that apply to Cocoa programming in general. If a delegate is not explicitly set, the stream object itself becomes the delegate a useful convention for custom subclasses.
The atomic write begins by writing the data to a temporary file.
If you iterate over a lot of objects, you may need to use local autorelease pool blocks to ensure temporary objects are deallocated as soon as possible. The XML and binary stores require that the whole object graph reside in memory, and store writes are atomic see Persistent Store Features which means that they do not efficiently deal with large data objects.
Your input helps improve our developer documentation. Background I am attempting to write relatively large files video to disk on iOS using Swift 2.
Also set a delegate.
Swift 4 write array to file
The NSData class and its subclasses provide methods to quickly and easily save their contents to disk. Note on the extension I've added a completion handler to the base writeToURL to ensure that no unintended resource sharing occurs. Some of the options involve use of an InputStream as well. I can transpose the algorithm into appropriate Swift compatible constructs. You can also use patterns that apply to Cocoa programming in general. For example, you could create an input stream that maintains statistics on the bytes it reads; or you could make a NSStream subclass whose instances can seek through their stream, putting back bytes that have been read. The task needs to be done without blocking the Main UI, while using completion logic, and also ensuring that the operation happens as quickly as possible. Managed objects maintain strong references to each other through relationships, which can easily create strong reference cycles. Shall I rather make a separate class, using its own serial queue, for accessing and modifying the dataToWrite buffer, perhaps? Note: I've moved the logic below into the completion handler see the code above and I no longer see any error. Schedule the stream object on a run loop and open the stream. So when dealing with large files one is at the mercy of whatever internal mechanism is at work within the NSData methods. Although there are strong similarities between the Cocoa and Core Foundation stream APIs, their implementations are not exactly coincident.
Avoid using the writeToURL:atomically: method and the related methods when working inside a publicly accessible directory.
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