QSFD — COBOL FD interception program

QSFD and QSFDADV are CALLable QUICKSTART programs which a COBOL program can invoke to begin interception of COBOL I/O verbs for a given FD file. This allows the application program to continue using COBOL verbs for I/O rather than converting to making CALLs to QUICKSAM. QSFD/QSFDADV get called before and after each COBOL OPEN verb and after a COBOL CLOSE verb. QSFDADV is used for output sequential files which use COBOL's WRITE AFTER ADVANCING or APPLY WRITE-ONLY option. QSFD and QSFDADV operate only for physical sequential datasets. For other datasets, CALL the QUICKSAM API directly.

Rather than coding the API CALLs to QSFD and QSFDADV, a set of provided INCLUDE or COPY files are normally used instead. These files can be included more easily than coding the CALL statements. See FD-interception-technique for examples.

When using Transparent Mode, these CALLs are automatically generated.