unsafe-pointers

In C you can put function pointers into an array of void pointers and convert them back to function pointers of any type: extern int (*fn1)(void); extern void (*fn2)(int); void foo(void) { void *array[2]; int i; /* implicit cast from function pointer to void pointer */ array[0] = fn1; array[1] = fn2; for (i = 0; i < 2; i++) { int (*fp)(int, int, int); /* implicit cast from void pointer to function pointer */ fp = array[i]; /* call function with a different signature */ fp(1, 2, 3); } } I need to do the same in Go, using unsafe.Pointers. The questions are: Can a Go function pointer be converted

I want to get pointer of first entry in the array. This is how I tried int[] Results = { 1, 2, 3, 4, 5 }; unsafe { int* FirstResult = Results[0]; } Get following compilation error. Any ideas how to fix it? You can only take the address of an unfixed expression inside of a fixed statement initializer The error codes are magic to get the answer - search for error code (CS0212 in your case) and you get explanation with proposed fix in a lot of case. Search: http://www.bing.com/search?q=CS0212+msdn Result: http://msdn.microsoft.com/en-us/library/29ak9b70%28v=vs.90%29.aspx Code from the page:

I have been doing some unsafe bitmap operations and have found out that increasing the pointer less times can lead to some big performance improvements. I am not sure why is that so, even though you do lot more bitwise operations in the loop, it still is better to do less iterations on the pointer. So for example instead of iterating over 32 bit pixels with a UInt32 iterate over two pixels with UInt64 and do twice the operations in one cycle. The following does it by reading two pixels and modifying them (of course it will fail with images with odd width, but its just for testing). private

This has been asked before, but something must have changed in Swift since it was asked. I am trying to store CMSampleBuffer objects returned from an AVCaptureSession to be processed later. After some experimentation I discovered that AVCaptureSession must be reusing its CMSampleBuffer references. When I try to keep more than 15 the session hangs. So I thought I would make copies of the sample buffers. But I can't seem to get it to work. Here is what I have written: var allocator: Unmanaged<CFAllocator>! = CFAllocatorGetDefault() var bufferCopy: UnsafeMutablePointer<CMSampleBuffer?> let err =

I have a receipt validation class that is deprecated since Swift 3 has released. I fixed some issues, but I still have many ... Here is the GitHub source code I used : https://gist.github.com/baileysh9/4386ea92b047d97c7285#file-parsing_productids-swift and https://gist.github.com/baileysh9/eddcba49d544635b3cf5 First Error : var p = UnsafePointer<UInt8>(data.bytes) Compiler throws : Cannot invoke initializer for type UnsafePointer(UInt8) with an argument list of type UnsafeRawPointer Second error while (ptr < end) Binary operators < cannot be applied to two UnsafePointer(UInt8) operands Thank