Automated File Creation - Job Optimizer Pipes implementation

The file is created by the writer because the writer has the authority to create it. A new DD statement (dynamically or manually defined) is used for file creation. When the application writes to the pipe through its standard DD statement, Job Optimizer Pipes writes the data to the pipe and the physical file by using the new DD statement. The file DCB attributes are equal to the pipe DCB attributes. When the physical file is deallocated (usually at step termination), its disposition is determined according to the DISP specifications from its DD statement. The file can then be used by a subsequent application that cannot work in parallel with the writer.

The pipe readers access the data from the pipe without accessing the physical file and without performing physical I/O. The reader does not affect physical file creation or disposition. During standard processing (without a pipe), the writer usually creates a file that is read and deleted by the reader. However, when using pipes with automated file creation, the file is not accessed by the reader and is not deleted at the end of the process.

A file can be created when the pipe is dynamically set or when the pipe is defined in JCL or in dynamic allocation.

The file creation process is performed when all of the following conditions have been satisfied:

• There is a matching Pipe Rule for a data set.

• The participant is identified as a writer.

• The Create file option in the Pipe Rule contains the value WTR.

• Only one writer can participate in a pipe when a file is created.

This section provides the following topics: 

• File creation when a pipe is dynamically set
• File creation when a pipe is defined through JCL