Function renew 

pub fn renew(
    folder: &Path,
    key: &[u8; 32],
    part: &str,
    computer: &str,
    now: i64,
    active: i64,
    take: bool,
    rule: Rule,
    wrote: Option<(u32, u64)>,
) -> Result<Keeper, String>

This computer’s claim on part, renewed (made the first time): active is when you were last at this computer, take takes the part on purpose, wrote how far it wrote its records. Returns who keeps it now.