pub fn claim(runs: &Path, stamp: &str) -> Result<(String, PathBuf)>Expand description
Claim a fresh workspace below runs for a migration opened at
stamp, and return its identifier with its path.
The claim is the snapshots’ own exclusive create, so a second archive
in the same second takes <stamp>-2, and the identifier carries the
counter.
§Errors
Any I/O error creating the workspace.