IBM OS/390 User Manual
8.1.5.4 Statement Compatibility
All batch programs using the calls, GU - GHU - GN - GHN - GNP - GHNP - ISRT -
DLET - REPL, are transportable to MVS with no modification to the DLI calls. Of
course, these programs may need changes for other reasons and they must be
recompiled on the MVS system. VSE JCL is changed to MVS JCL, and the DL/I
parameters external to the program (that is, HSBFR and HDBFR bufferpool) are
written differently even though they perform the same functions. They are
defined in the IMS/ESA control data set DFSVSAMP. This is described in the
IMS/ESA Installation Volume 2: System Definition and Tailoring manual.
DLET - REPL, are transportable to MVS with no modification to the DLI calls. Of
course, these programs may need changes for other reasons and they must be
recompiled on the MVS system. VSE JCL is changed to MVS JCL, and the DL/I
parameters external to the program (that is, HSBFR and HDBFR bufferpool) are
written differently even though they perform the same functions. They are
defined in the IMS/ESA control data set DFSVSAMP. This is described in the
IMS/ESA Installation Volume 2: System Definition and Tailoring manual.
The languages common to DL/I and IMS/ESA are PL/I, COBOL/VS and
Assembler. RPG II is not supported by IMS/ESA, but RPG/370 is.
Assembler. RPG II is not supported by IMS/ESA, but RPG/370 is.
The status codes tested with DL/I are valid with IMS/ESA and have the same
meanings with some exceptions which are covered below.
meanings with some exceptions which are covered below.
8.1.5.5 Field Level Sensitivity
Basic support is compatible between DL/I and IMS/ESA. If DL/I extensions are
used, changes may be required to application programs as well as to database
definitions. Status codes starting with
used, changes may be required to application programs as well as to database
definitions. Status codes starting with
′
K
′
will not be returned by IMS/ESA.
8.1.5.6 PCB after GE Status
There is a difference in the information returned with the GE status code
following a number of GNP calls. In DL/I the segment name returned is that of
the last successfully retrieved segment. In IMS/ESA, the segment name returned
with the GE status code is that of the parent segment.
following a number of GNP calls. In DL/I the segment name returned is that of
the last successfully retrieved segment. In IMS/ESA, the segment name returned
with the GE status code is that of the parent segment.
8.1.5.7 NI Status Codes
DL/I requires a user to manually correct a database following an NI status code.
IMS/ESA automatically fixes this error condition.
IMS/ESA automatically fixes this error condition.
8.1.5.8 CHKP Calls
While the written form of the CHKP call is the same, the PCB-name specified in
IMS/ESA must refer to the first PCB in the PCBLIST. This PCB is called the I/O
PCB and is generated with the CMPAT option in PSBGEN. Since this is a new
PCB, application programs will have to be changed to reflect the existence of
this PCB.
IMS/ESA must refer to the first PCB in the PCBLIST. This PCB is called the I/O
PCB and is generated with the CMPAT option in PSBGEN. Since this is a new
PCB, application programs will have to be changed to reflect the existence of
this PCB.
8.1.5.9 GSCD and/or GSTA Calls
These must be reviewed for the following reasons:
1. GSCD has a c o m m o n format and returns the address of the SCD area.
However, the SCD DSECT layout is not the same and label names may differ.
2. DL/I supports the GSTA call for application programs running across
separate VSE/VAE address spaces. This allows access to DL/I statistics
when DL/I Multiple Partition Support (MPS) applications are running in
separate VAE address spaces. The IMS/ESA STAT call provides similar
functions.
when DL/I Multiple Partition Support (MPS) applications are running in
separate VAE address spaces. The IMS/ESA STAT call provides similar
functions.
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VSE to OS/390 Migration Workbook