filecopy

Overview ¶

Package filecopy puts one file somewhere else, as a real file.

It is one function in its own package because two callers need exactly it and for the same reason. A sandbox is only a sandbox if what it holds is a copy: a symlink is a reference that `go:embed` refuses and a write follows through to the original, and a hard link shares the inode so a write reaches it too. See docs/experiments/the-sandbox-is-a-reference.md.

fsrepository materialises the index this way, and staged fills in what git does not carry the same way. Written twice, the two would drift.