Abstract: A set of application programming interfaces (“APIs”) is provided that enables an application to perform operations on multiple system resources as a single logical unit of work through a transaction. The application can then commit or roll back the entire group of changes as a single unit in a coordinated manner. The APIs expose functions and methods that take a reference to a transaction context, such as a handle, name, or pointer, as one of their parameters so that the application can manipulate the resource as a transacted operation. The transaction is bound to all created handles so that all operations on the resource using those handles are also transacted. In an illustrative example, the set of APIs are transacted name-based WIN32 APIs that take a transaction handle. The transacted APIs expose transacted operations to the application for durable system resources in the OS kernel, including the NTFS file system (New Technology File System) and registry.

Abstract: A security model is provided in a transactional logging infrastructure that is arranged as a protected subsystem built on an underlying secure file system. Files in the underlying file system used by virtual log streams are protected from direct user writes, and are written-to only through the protected subsystem that is brokered by a machine-wide principal so that virtual log files sharing the same multiplexed physical log are kept secure from each other. Log file handles and user- and kernel-mode objects are exposed to log clients through interfaces using consistent security semantics for both dedicated and virtual logs. Log clients are agnostic of the underlying secure file system and can only manipulate file system containers—abstract objects that implement the physical log and used to virtualize the file system by normalizing input/output operations—by using the interfaces brokered by the principal in the protected subsystem.

Abstract: A transactional logging service is provided to user-mode and kernel-mode log clients by utilizing a marshalling area to buffer a set of log records that a log client assembles into a log stream. Disk I/O (input/output) functionality is then separately brokered using a kernel-mode address space for a single dedicated physical log, or virtual logs multiplexed to a single log, which is written to stable storage that contains log records from across all of the log streams. Physical log writes are handled by a shared log flush queue and physical log reads are provided by a file system cache that underlies the service. A multi-level cache hierarchy is utilized when a log client needs to access a log record. A series of caches are queried in order of increasing latency until the targeted log record is located. The target log record is only read from disk in the event that it missed at each cache in the hierarchy.

Abstract: A system and method for improved software servicing by installation of an updated version is provided. Using branch versioning techniques that support multi-branch development and release versioning techniques that support multi-version development, an update package may include updated files for each branch or release version. The least possible version from the update package may be installed to minimize the risk for potential software bugs introduced by the high frequency of changes made to a higher version. Additionally, any fix installed on a target machine running a particular version may be migrated when updating the target machine to a new version without losing the fix and regressing the change. Such an update may be uninstalled by reverse migration of any fixes before uninstalling files from the version update.

Abstract: An automated warehouse system row cart includes a lifter that uses cams to raise and lower pallets. Three symmetrical cam lobes are cut into a hollow cylinder. Three matching cam lifters ride these lobes and are attached to an elevator plate. A stepper motor running in one direction is used to raise and lower the elevator plate by virtue of the action between the cam lobes and lifters.