In a fluid pressure cylinder with a magnetostriction type position detecting device for detecting an operating position of a piston using the position detecting device, the fluid pressure cylinder is provided with a simple and rational design structure without providing it with a special conductive member as a current feedback conductor. Thus, it is possible to reliably detect an abnormality that has occurred in the vehicular hydraulic pressure control circuit. An archive key generation process can be based on a random value generation, an algorithm for generating keys with specific characteristics, an indexing scheme, a progressive enciphering scheme or a shared secret scheme. Also disclosed are a fluid collector and a fluid collection device. If the first sensor is not actuated, the sensor module is electrically isolated and does not consume any power. The low dopant concentration in the semiconductor layer increases the mobility of the carriers in the channel of the semiconductor transistor structure.