Guardian Application Conversion Guide

Using Sequential I/O (SIO) Procedures
Converting Other Parts of an Application
096047 Tandem Computers Incorporated 8–17
Using Sequential I/O
(SIO) Procedures
An existing program that calls Sequential Input/Output (SIO) procedures can run
under the D-series operating system without any changes. However, you must
convert specific SIO procedure calls and declarations in a program if:
The program uses SIO procedures to read D-series system messages from
$RECEIVE
The program identifies high-PIN process openers using process handles rather
than process IDs
The D-series SIO procedures include these changes:
There are no new SIO procedures; the SET^FILE, CHECK^FILE, and OPEN^FILE
procedures are modified to support D-series features.
The GPLDEFS file contains the D-series SIO declarations, including LITERAL and
DEFINE declarations.
The file control block (FCB) is 20 words larger and contains new fields for primary
and backup process handles.
The conversion required for applications that call SIO procedures is described in the
following subsections. For a description of each SIO procedure, refer to the Guardian
Procedure Calls Reference Manual.
Using the GPLDEFS File Your existing program should copy the $SYSTEM.SYSTEM.GPLDEFS file, which
contains TAL DEFINE and LITERAL declarations required by the SIO procedures.
Make sure that your program copies a D-series version of the GPLDEFS file. This file
contains a new section called FCB^DEFS^D00, which has these additions:
The LITERAL declaration for the size of a D-series FCB is FCBSIZE^D00. Each
D-series FCB, including the common FCB, uses 80 words of user data space
(a C-series FCB is 60 words).
The DEFINE declaration for allocating the common FCB is ALLOCATE^CBS^D00.
The DEFINE declaration for allocating the FCB for each file is
ALLOCATE^FCB^D00.
The DEFINE and LITERAL declarations for the SET^FILE, CHECK^FILE, and
OPEN^FILE procedures are revised as described in the following subsections.