The following are considerations, restrictions, and limitations that apply to the use of zSeries host data internal representation. The BINARY, CHAR, and FLOAT compiler options determine whether zSeries host data format or native data format is used (other than for COMP-5 items or items defined with the NATIVE phrase in the USAGE clause). (The terms “host data format” and “native data format” in this information refer to the internal representation of data items.)
CICS allows you to specify various data conversion choices at various places and at various granularities. For example, client CICS translator option specifications on the server for different resources (file, EIBLK, COMMAREA, transient data queue, and so forth). Your use of host or native data representation depends on such selections. Refer to the appropriate CICS documentation for specific information about how such choices can best be made.
There is no zSeries host data format support for COBOL programs that are translated by the separate or integrated CICS translator and run on TXSeries.
You can use the date and time callable services with the zSeries host data format internal representations. All of the parameters passed to the callable services must be in zSeries host data format. You cannot mix native and host data internal representations in the same call to a date and time service.
Due to differences in the limits of floating-point data representations on the Windows workstation and the zSeries host, it is possible if FLOAT(HEX) is in effect that a floating-point overflow exception could occur during conversion between the two formats. For example, you might receive the following message on the workstation when you run a program that runs successfully on the host:
IWZ053S An overflow occurred on conversion to floating point
To avoid this problem, you must be aware of the maximum floating-point values supported on each platform for the respective data types. The limits are shown in the following table.
| Data type | Maximum workstation value | Maximum zSeries host value |
|---|---|---|
| COMP-1 | *(2**128 - 2**4)
(approx. *3.4028E+38) |
*(16**63 - 16**57)
(approx. *7.2370E+75) |
| COMP-2 | *(2**1024 - 2**971)
(approx. *1.7977E+308) |
*(16**63 - 16**49)
(approx. *7.2370E+75) |
| * Indicates that the value can be positive or negative. | ||
As shown above, the host can carry a larger COMP-1 value than the workstation and the workstation can carry a larger COMP-2 value than the host.
The zSeries host data format compiler options can be used with DB2 programs.
The zSeries format of binary and floating-point data items must not be specified for arguments or returning items in INVOKE statements.
The zSeries host data format compiler options should not be used with MQ programs.
All of the zSeries host data formats except DBCS (USAGE DISPLAY-1) can be used as sort keys.
related concepts
Formats for numeric data
related tasks
Coding interoperable data types in COBOL and Java
related references
Compiler options