A method for managing idle processing in a computer system is described. An Idle Chain Manager virtual device driver (VxD) address is registered on an idle callback chain on the computer system. An Idle Chain Manager callback function corresponding with the Idle Chain Manager VxD address is hooked with a registration service on the computer system. This allows the Idle Chain Manager callback function to intercept a request from a VxD to register a VxD idle callback address onto the idle callback chain and registers the VxD idle callback address with the Idle Chain Manager callback function. The Idle Chain Manager VxD address is called when the idle processing is required.

The invention also known as "Disk-saver" employs a novel method of controlling the power to the hard disk drive of an electronic digital computer. A "Terminate and Stay Resident" (TSR) program is executed in the electronic digital computer which provides the timing function to determine when the hard disk drive should be turned off. When the decision is reached to turn the power on or off, the TSR program generates an ultrasonic coded signal which is sent to a loudspeaker to which the disk-saver module of this invention is connected to monitor the ultrasonic coded signal. When the signal is generated the Disk-saver module of this invention turns the power to the disk drive on or off as directed by the coded ultrasonic signal.

The present invention provides a method and apparatus for performing a multipoint polling protocol which employs silence intervals for controlling operation of the multipoint circuit. When a tributary station which has no data to send is polled by a control device, the tributary station does not send any signal in response to the poll. The control device measures the time which has lapsed since the last poll was sent and compares it to a "no-data" silent threshold timing interval. When the elapsed silent time exceeds the threshold interval, the control device assumes that the tributary has no data to send and immediately sends the next message. If the beginning of a non-silent response is detected before the threshold interval has passed, the control device receives the response and processes the response in the normal manner, e.g., in the manner in which typical multipoint polling protocols process responses. Before issuing a poll to a low-speed device, the control device allows a predetermined delay period of silence to elapse between the end of the last transmission on the line and the start of the poll transmission. This delay period is longer than the no-data threshold interval. All tributary stations measure this silent delay interval and, when it occurs, they prepare to receive a low-speed modulation transmission from the control device. When the period of silence does not exceed the predetermined silent delay interval, the low-speed devices know they will not be able to demodulate the received high-speed signal and, therefore, disable their receivers until energy is no longer detected on the line. When the tributary stations are connected to the subscriber line via a shared bus, the tributary stations determine whether a transmission is from another tributary station or from the control device based on a silent delay interval which occurs after the last transmission on the subscriber line.

A novel method of and system and procedures for more accurately measuring the resource usage of UNIX processes by sampling methods involving appropriate corrections for the resource usage of the terminated processes and analyzing UNIX process data along with subsystem data such as RDBMSs, allowing system administrators and mangers to get a much better picture of who is using the resources on the system and thus perform a better job at performance analysis and capacity planning, the technique also enabling and reducing the error in the process measurements collected by sampling of the resources usage measured by the operating system and correlating the measurements taken by subsystems with the measurements taken by the operating system.

A narrow array capacitive semiconductor fingerprint detection system includes an array of capacitive sensing elements. The array has a first dimension about the width of a fingerprint and second dimension less than the length of a fingerprint. A scan control unit is coupled to scan the array at a scan rate determined by the speed of finger movement over the array. The scan control unit scans the array capture partial fingerprint images. Output logic is coupled to the array to assemble the captured fingerprint images into a complete image based upon the direction of finger movement over the array. A mouse device is positioned adjacent the array in the path of finger movement over the array. The mouse device is coupled to provide finger movement speed information to the scan control unit. The mouse device is also coupled to provide finger movement direction information to the output logic.