File Status Comparisons

This section documents the anomalies in file status settings based upon the environment in which the I/O statements are executed. Expected results, including expected anomalies (for example, the order of records returned when reading an alternate index in reverse order), are not included in this list unless they help clarify the conditions under which the anomalies were detected.

These results were compiled from a set of test programs executed in the following three environments:

The test programs used an extensive combination of file definitions (organization and access mode), open types (INPUT, I/O, OUTPUT, EXTEND, etc.), and I/O verbs for example READ, WRITE, REWRITE) to examine the behavior of execution environment and the results of the file status information returned to the test programs.

In the Cross Reference of File Status Setting table that follows, file status information obtained for the tests in each environment is displayed in the format 'a/b', where 'a' represents the first byte of the file status (file status 1) and 'b' represents the second byte of the file status (file status 2).

For run-time errors, the first byte displayed is '9' and the value for the second byte is the ordinal value of the file status 2 field (e.g. 9/100). When an I/O operation is invalid, a key of 'N/A' is used. When an I/O operation is valid but was not tested because of the results of an earlier I/O operations, a file status of '-/-' is used.