New minimal B-tree implementation

 In the last couple of days I wrote a minimal B-tree implementation (based on previous work, of course). The link is here: https://github.com/tomjridge/mini-btree

This B-tree is resistant to write reordering, that is, the block device can reorder writes, and crash, and the B-tree will still function correctly (although obviously some recent operations may not have flushed fully to disk unless you managed a sync before the crash).




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