handle_close - close a handle
#include <zircon/syscalls.h>
zx_status_t zx_handle_close(zx_handle_t handle);
handle_close() closes a handle, causing the underlying object to be reclaimed by the kernel if no other handles to it exist.
If the handle was used in a pending object_wait_one or a object_wait_many call, the wait will be aborted.
If the handle was the next to last handle to the object. The last handle to the object will assert the ZX_SIGNAL_LAST_HANDLE signal.
It is not an error to close the special "never a valid handle" ZX_HANDLE_INVALID, similar to free(NULL) being a valid call.
handle_close() returns ZX_OK on success.
ZX_ERR_BAD_HANDLE handle isn't a valid handle.