free

        # IO::Buffer.free

(from ruby core)
### Implementation from Buffer
---
    free -> self

---

If the buffer references memory, release it back to the operating
system.
*   for a *mapped* buffer (e.g. from file): unmap.
*   for a buffer created from scratch: free memory.
*   for a buffer created from string: undo the association.


After the buffer is freed, no further operations can't be performed on
it.

    buffer = IO::Buffer.for('test')
    buffer.free
    # => #<IO::Buffer 0x0000000000000000+0 NULL>

    buffer.get_value(:U8, 0)
    # in `get_value': The buffer is not allocated! (IO::Buffer::AllocationError)

    buffer.get_string
    # in `get_string': The buffer is not allocated! (IO::Buffer::AllocationError)

    buffer.null?
    # => true

You can resize a freed buffer to re-allocate it.