| 摘要 |
PURPOSE:To realize parallel executing operations between the conflicting data processes by defining the record formation of two files in the same form and selecting one of both records for writing and the other for reading to ensure the parallel operations when a writing action conflicts with a reading action. CONSTITUTION:When a writing job is carried out, a write processing unit 6 fetches the name of a file to undergo a writing process out of a file control table 3. Then the unit 6 locks a file 1 and inhibits the execution of other processes to the file 1. Then the file 1 is opened and data are written. When a reading job is carried out, both files 1 and 2 are locked and an exchanging process is carried out so that the files 1 and 2 are used for reading and writing jobs respectively. Then a lock state is released between both files 1 and 2 and the file 1 is opened to read the contents of the written data. Thus it is possible to carry out both reading and writing processes at one time and at any time except a lock control state.
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