pub fn available_bytes(path: &Path) -> Option<u64>Expand description
Free (available-to-this-user) bytes on the filesystem backing path.
Returns None when the probe fails (path doesn’t exist yet, an
unsupported platform, a transient stat error). Callers treat None
as “headroom unknown” and degrade to a no-op rather than abort — the
guard must never manufacture a failure from a probe gap.
fs4::available_space reports the space available to an unprivileged
process (statvfs f_bavail × f_frsize on unix, the caller-quota
figure from GetDiskFreeSpaceExW on Windows) — the correct number for
“will this write succeed”, as opposed to total free including
root-reserved blocks.