The I/O feedback area is a part of the open data path for the file that is updated after each successful non-blocked I/O operation. If record blocking is taking place, the I/O feedback is updated after each block of records is transferred between your program and the Data Management system.
The I/O feedback consists of two parts: one part that is common to all file types, and one part that is specific to the type of file.
To assign a pointer to the common part of the I/O feedback area, use the _Riofbk() function. To assign a pointer to the part of the I/O feedback area that is specific to the type of file, add the offset contained in the file_dep_fb_offset field of the common part to a pointer to the common part.
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