code: func BufferStorageExternalEXT(target uint32, offset int, size int, clientBuffer unsafe.Pointer, flags uint32) {
  	syscall.Syscall6(gpBufferStorageExternalEXT, 5, uintptr(target), uintptr(offset), uintptr(size), uintptr(clientBuffer), uintptr(flags), 0)
  }
docs: // Parameter clientBuffer has type C.GLeglClientBufferEXT.