Abstract: An embodiment of the invention provides an apparatus and a method for direct switching of software threads. The apparatus and method include performing acts including: issuing a wakeup call from a first thread to a second thread in a sleep state; removing the second thread from the sleep state; switching out the first thread from the resource; switching in the second thread to the resource; and running the second thread on the resource.

Abstract: In an embodiment of the invention, an apparatus and method for a target thread selection in a multi-threaded process perform the steps of receiving a signal that may or may not be masked by threads in the process; and searching a thread subset for a target thread that can handle the signal. A signal daemon may search for the target thread if the target thread is not found in the thread subset.

Abstract: To handle a signal received at an application context that employs a remote kernel service implemented in a server context different from the application context, the remote kernel service receives from the application context a first signal. Using a signal action vector file associated with the server context, a first action code associated with the first signal is ascertained. If the first action code represents a pseudo-handler, the remote kernel service is aborted.

Abstract: Systems, methods, and device are provided for program stack handling. One method embodiment includes recognizing that a fault has occurred because a particular address range in a memory stack has been accessed. The method includes evaluating a current utilized size of regions in the memory stack. A particular address range between the current utilized size of regions in the memory stack is then relocated.

Abstract: An embodiment of the invention provides an apparatus and a method for direct switching of software threads. The apparatus and method include performing acts including: issuing a wakeup call from a first thread to a second thread in a sleep state; removing the second thread from the sleep state; switching out the first thread from the resource; switching in the second thread to the resource; and running the second thread on the resource.

Abstract: A method of allocating memory and a memory allocation apparatus are described. The method comprises allocating a set of memory locations for at least a portion of a data structure, wherein the allocated set comprises memory space storing a counter corresponding to each memory location in the set. A method of traversing a data structure is described. The method comprises incrementing, by a predetermined value, a reference address of a pointer to a first data structure of a portion of a set of allocated memory locations to obtain a reference address to a second data structure in the portion of the set. The portion of the set of allocated memory locations comprises a counter for each allocated memory location.

Abstract: An embodiment of the invention provides an apparatus and a method for avoidance of a masked signal trap loop. The apparatus and method perform acts including: terminating a process of an application and generating a core dump file, if parameters are set in an error detection engine and a signal is masked when a coding error is encountered in the application.

Abstract: A method of handling a signal for delivery to a process in a process group along with an apparatus and computer-readable medium storing instructions therefore are described. The method comprises obtaining a lock on a portion of a process group management structure and storing a signal to the process group management structure, wherein the signal is to be delivered to one or more processes of a process group, wherein an operating system manages the process group management structure. The method further comprises transmitting a wakeup signal to a signal daemon and releasing the obtained lock. A method of delivering a signal to a process in a process group is also described. The method comprises obtaining a signal from a process group management structure, obtaining a lock on a process list, transmitting the signal to a process specified in the process list; and releasing the lock on the process list.

Abstract: In an embodiment of the invention, an apparatus and method for a target thread selection in a multi-threaded process perform the steps of receiving a signal that may or may not be masked by threads in the process; and searching a thread subset for a target thread that can handle the signal. A signal daemon may search for the target thread if the target thread is not found in the thread subset.

Abstract: A method in a computer for facilitating interaction between an application program and a subsystem is disclosed. The method includes providing a virtual process file system layer. The virtual process file system layer is configured to interact with the subsystem in a substantially content-independent manner. The method additionally includes providing a content dependent module, the content dependent module being associated with the subsystem and is configured interact with the subsystem in a content-dependent manner. The method further includes providing a directory structure table, the directory structure table being configured to track a name of the content dependent module, wherein the content-dependent module is configured to be registered with the directory structure table using a dynamic name.

Abstract: A method in an operating system of a computer for allowing a plurality of application programs to interact with a plurality of subsystems, at least two application programs of the plurality of application programs being associated with two different personalities. The method includes providing a plurality of modules, each of the plurality of modules being associated with at least one personality and configured to interact with one of the plurality of subsystems, at least two modules of the plurality of modules being associated with the two different personalities.

Abstract: A method in a computer for facilitating interaction between an application program and a subsystem is disclosed. The method includes providing a virtual process file system layer. The virtual process file system layer is configured to interact with the subsystem in a substantially content-independent manner. The method additionally includes providing a content dependent module, the content dependent module being associated with the subsystem and is configured interact with the subsystem in a content-dependent manner. The method further includes providing a directory structure table, the directory structure table being configured to track a name of the content dependent module, wherein the content-dependent module is configured to be registered with the directory structure table using a dynamic name.

Abstract: A file system in a computer is disclosed. The file system is configured to service file access requests between an application program and a first data storage subsystem. The file system includes a first persistent module coupled to receive a first file access request. The first persistent module is associated with the first data storage subsystem. The first file access request pertains to the first data storage subsystem. The file system includes a first transparently unloadable module coupled to the first persistent module to service the first file access request. The first transparently unloadable module is configured to be dynamically unloadable from the computer, wherein the first persistent module includes a blocking arrangement for blocking the first file access request at the first persistent module to allow the first transparently unloadable module to be unloaded without causing an error in the application program.

Abstract: A method in an operating system of a computer for allowing a plurality of application programs to interact with a plurality of subsystems, at least two application programs of the plurality of application programs being associated with two different personalities. The method includes providing a plurality of modules, each of the plurality of modules being associated with at least one personality and configured to interact with one of the plurality of subsystems, at least two modules of the plurality of modules being associated with the two different personalities.

Abstract: A power limiter is provided consisting of two cells of optically transparent material having a low index of refraction, but a large third order susceptibility to electric polarization. The input cell has a positive susceptibility which self-focuses intense radiation beams (i.e., laser beams) and the output cell has a negative susceptibility which scatters the even more intense self-focused beam by self-defocussing.

Abstract: An optical material having an index of refraction dependent on wavelength of incident radiation is used between the reflectors of an off-normal Fabry-Perot cavity used as an interference filter. External to the cavity, and in the direction of incident radiation, another optical material having an index of refraction dependent on wavelength of radiation is placed. The incident radiation is thus refracted into and within the cavity dependent on its wavelength. By proper choice of the indices of refraction, and other variables, the filter may be designed to exactly match the output spectrum of a line spectrum laser, and to transmit all spectral lines of the laser, but to reflect all other radiation of interest.

Abstract: An optical material having an index of refraction related to wavelength is placed between the reflectors of a Fabry-Perot cavity employed as an interference filter. The cavity is skewed with respect to the optical path of incident radiation such that the material diverts the optical paths of different spectral lines and the filter response more nearly matches the line spectrum.

Abstract: A filter is constructed consisting of an optical cavity having at least one element which is a square mesh of highly-conductive metal on a transparent substrate. The mesh openings are defined by relatively narrow conductors of the metal. The mesh feature size, as determined by the sum of the conductor width and square size length, is below the diffraction limit for incoming radiation of interest.

Abstract: Incident radiation is focussed by a lens into a non-linear optical material whose index of refraction increases with increased radiation intensity. For normal radiation, the radiation freely passes through the nonlinear optical and an optically-switchable material to an other lens. This other lens directs the radiation onto a photodetector. High-intensity radiation, however, is self-trapped in the nonlinear material to form a columnar beam which falls on the optically-switchable material, causes this material to switch, and is reflected thereby.

Abstract: A trilaminar semiconductor device is placed at an intermediate focus is an optical instrument having a sensitive photodetector. The layers of the device are successively in the form of a two-photon absorber, a sacrificial layer, and a multiple quantum well. The composition of the semiconductor is varied in the layers to achieve the desired bandgap and function.