摘要 |
A method of sharing dataspaces among a plurality of applications on IBM mainframe computers. A DataServ Routing Table (DSRT) is anchored in an extended command storage area (ECSA) by a pointer stored in a SubSystem Communications vector Table (SSCVT) which also resides in the ECSA. The DSRT identifies all DataServ tasks using pointers to DataServ Vector Tables (DSVT), which are created by each DataServ task in the ECSA. Each DSVT contains a pointer to a DataServ task, as well as a pointers to associated Dataspace Information Element (DSIE) and DataServ Application Descriptor (DSAD) pools. The DSIEs contain a description of each dataspace created by the DataServ task. The DSADs contain a description of each application currently accessing a dataspace created by the DataServ task. Each DataServ task is responsible for creating one or more dataspace, mapping a linear dataset to the dataspace, and then making the dataspace available to authorized applications by creating its associated DSVT, DSIEs, and DSADs. An application communicates with the DataServ task through a DataServ Application Interface (DSAPPL), which is a set of service routines for accessing the DSRT, DSVT, DSIEs, and DSADs to provide direct addressability to the dataspaces.
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