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objective-cbuffernsdata

Does [NSData getBytes: length:] change position in buffer?

I have some NSData instance with 2 bytes of different value.

Will calling getBytes: of any kind (length, range...) also advance the current position in the buffer?

Example:

NSData *data = ...; // 2 bytes data
[data getBytes:&whatever1 length:1]; // reading first byte
[data getBytes:&whatever2 length:1]; // reading first OR second byte?

Will the contents that I get on each time getBytes:length: is called be the same first byte in the NSData instance or will the first call advance the next call to read from the second byte?

Thanks!

Solution

  • No, it does not.

    In the example it will access the same byte (first).

    To access the "next" byte you'll need to use getBytes:range: but, like @hot-licks commented, NSData is immutable and therefore won't be modified.