Z-MAP Plus I/O Access Library - Landmark Software Manager ...

Landmark Graphics Z-MAP Plus I/O Access Library
Using the Status Flag Option, ISTAT
Opening and Closing Files
If you are still having problems, attempt the same process in
Z-MAP Plus and see what the results are. Especially, check if the files,
master files and graphics files are good.
All errors should be printed by ZPI/O code. The application
programmer should check the code and decide what to do, but need not
write a message.
ISTAT 0 Fatal error occurred, application programmer should
close down subsystems, pictures, files, etc., for a clean
abend. Output arguments are printed but they may not
represent good values, depending on where the error
occurred.
For the Draw and Plot routines, the files must be closed.
Files should be opened when working with most of the File utilities.
Graphics files and pictures usually must be opened before Graphics
utilities can be performed.
If files or pictures are opened, they should be closed before terminating
the application program.
Every effort is made to close all files within a ZPI/O subroutine, but
sometimes some internal files may be left open. If you have trouble of
this kind, perform the following loop after the call in question. This
guarantees that the files are closed:
CALL SIname (
DO xxx, I = 1,5
CALL SIFCLO(I, ISTAT)
xxx CONTINUE
5000.0.0 ZPI/O Overview: Comments and Suggestions 30