@param io the context to operate in
@param o the name of the object
@param name the name of the lock
@param cookie user-defined identifier for the instance of the lock
@returns 0 on success, negative error code on failure
@returns -ENOENT if the lock is not held by the specified (client, cookie) pair
Release a shared or exclusive lock on an object.
@param io the context to operate in @param o the name of the object @param name the name of the lock @param cookie user-defined identifier for the instance of the lock @returns 0 on success, negative error code on failure @returns -ENOENT if the lock is not held by the specified (client, cookie) pair