How it works

Measuring the filesystem

Before any of that, `gitto` writes a 32 MB probe file, clones it with the system call, and compares free space before and after. A copy that consumed the probe's own size was a full copy, whatever the exit status said.

Before any of that, gitto writes a 32 MB probe file, clones it with the system call, and compares free space before and after. A copy that consumed the probe's own size was a full copy, whatever the exit status said.

This matters because cp -c on macOS falls back to a full copy on a filesystem without clonefile and reports success. A check that read the exit status would call a 13 GB full copy a clone.

Re-addressing

Then it walks what the copy now claims about itself and applies one of three dispositions.

Q&A

Short answers to what people ask before they install it.