Enabling Unicode and Code Page Support

This document covers the following topics:

International Components for Unicode for Software AG (ICS)

Code page conversion and Unicode support make use of functionality provided by International Components for Unicode for Software AG (ICS). If you want to enable Natural for Unicode and code page support, you have to install the components provided with ICS: the ICS module SAGICU or an alternative ICS module (z/VSE and z/OS only) and ICU data libraries.


  1. No ICS component must be installed to execute applications without Unicode and code page support, that is, when the profile parameters CFICU and CP are set to OFF.
  2. Information on the currently used ICU version and Unicode specification is provided in the main menu of the SYSCP utility. See Invoking and Terminating SYSCP in the Utilities documentation of the Natural for Mainframes documentation.


If you want to enable Natural for Unicode and code page support, you need to link and load the ICS module SAGICU or an alternative ICS module (z/OS and z/VSE only) during the installation of Natural as described in Installing International Components for Unicode for Software AG for z/OS, z/VSE and BS2000.

The ICS module SAGICU is intended to be used in most European countries as well as in North and South American countries. It contains a reduced set of code pages and locale IDs for English, German, French and Spanish language areas. Due to the reduced set of supported languages, it is relatively small.

The ICS module SAGICU contains the following:

Collation Services

Another feature of this module is collation services. Collation services are used to compare Unicode strings. They consider the fact that the alphabetical order varies from language to language. It is a big challenge to accommodate the world's languages and writing systems and the different orders that are used. However, the ICU collation service provides excellent means for comparing strings in a locale-sensitive fashion. For example, in German locale, the character "Ä" is sorted between "A" and "B"; in Swedish locale, it is sorted after "Z". In Lithuanian, the character "y" is sorted between "i" and "k". The ICU implementation of collation services is compliant to the Unicode Collation Algorithm and conforms to ISO 14651. The algorithms have been designed and reviewed by experts in multi-lingual collation, and are therefore robust and comprehensive.

Code Pages and Locales

The ICS module SAGICU provides the following code pages and locales:

Code Pages Locales

US (alias for IBM01140)
DE (alias for IBM01141)
ES (alias for IBM01145)
EN (alias for IBM01146)
FR (alias for IBM01147)
EDF03DRV (BS2000 code page)
EDF03IRV (BS2000 code page)
EDF04DRV (BS2000 code page)
EDF04IRV (BS2000 code page)
EDF041 (BS2000 code page)
EDF04F (BS2000 code page)
IBM-290 (Japanese code page SBCS)
IBM-930 (Japanese code page SBCS/DBCS)
IBM-939 (Japanese code page SBCS/DBCS)
IBM-1390 (Japanese code page SBCS/DBCS)
IBM-1399 (Japanese code page SBCS/DBCS)
IBM-932 (Japanese code page ASCII MBCS)
IBM-942 (Japanese code page ASCII MBCS)
IBM-943 (Japanese code page ASCII MBCS)
EUC-JP (Japanese code page ASCII MBCS)
IBM-420 (RTL code page)
IBM-424 (RTL code page)
IBM-916 (RTL code page)


Alternative ICS Modules for Support of Architecture Levels

This section does not apply to BS2000.

If your Natural system runs on z/OS or z/VSE with an IBM processor with architecture level 9 or higher, you can replace the ICS module SAGICU by SAGICUA9. SAGICUA9 is built to use advanced machine instructions introduced with IBM's ESA/390 and z/Architecture. You can use the system command TECH (see the System Commands documentation) to find out the architecture level supported on your current machine.

SAGICUA9 improves the execution performance, especially for Natural statements that use Unicode variables or code-page encoding instructions (for example, MOVE ENCODED). For more information on architecture levels, refer to the related documentation from IBM (z/Architecture, Principles of Operation).

An operation exception error (abend code S0C1) can occur if the ICS module SAGICUA9 is used, but the underlying machine architecture level is lower than 9.

Load Modules with Minimum Collation Data

Depending on the ICS Version installed at your site, you can use the load modules ICS231M and ICS231MA9 to include only the bare minimum of collation data in the module build. This enables a light-weight configuration and better performance for particular use cases.

ICU Data Libraries

If you want to enable Natural for Unicode and code page support, you need to link and load an ICU data library during the installation of Natural as described in Installing International Components for Unicode for Software AG for z/OS, z/VSE and BS2000.

ICU data libraries are supplied with the following ICS data modules where nn denotes the current version of the module as announced in the current Natural Release Notes for Mainframes.

Data Module Description
ICSDTnnE Contains the most popular code pages and locales. The code pages are already declared in NATCONFG.
ICSDTnnJ Same as ICSDTnnE, but enhanced by Japanese code pages. ICSDTnnJ is already linked to the ICS module SAGICU (or an alternative ICS module on z/VSE or z/OS). It contains the above mentioned code pages and locales.
ICSDTnnX Contains all possible converters and locales offered by the currently supported ICU version. It supports about 230 different code pages (predominantly EBCDIC code pages) and 238 locales. Therefore, the module size is huge.

ICSDTnnX supports all code pages and locale IDs which are supported by the currently supported ICU version (see http://demo.icu-project.org/icu-bin/convexp).

Due to technical restrictions, ICSDTnnX is not delivered for z/VSE and BS2000.

It is possible to create your own ICU data library that exactly matches your requirements (see Customizing the ICU Data Library).

ICU Data Items

The ICU data items supported by Natural include converters and collators. For example: a converter is used when a MOVE ENCODED statement executes, and a collator when strings are compared in an IF statement.

An ICU data item is either statically linked to an ICU data library or it is dynamically loaded on request during the Natural session.

ICU data items are supplied as loadable modules on the ICS data set supplied for installation of Natural, and must be accessible through the Natural steplib chain.

When a data item is used for the first time, ICS attempts to open it from the linked or loaded ICU data library. If no data item is associated with a library, ICS attempts to dynamically load the data item from the ICS data set.

This section covers the following topics:

Naming Conventions for Data Item Modules

The name of a data item module in the ICS data set is restricted to eight characters. As indicated in the table below, it consists of the following:

  • A prefix (I),

  • A two-digit ICU version (xx),

  • A logical group identifier (C, B, S, L, M or D), and

  • A four-digit sequence number (nnnn).

Module Name Contents
IxxCnnnn Charset mapping tables (converter modules)
IxxBnnnn Break iterators
IxxSnnnn Collators (collation services)
IxxLnnnn Localization (formatting, display names and other localized data)
IxxMnnnn Miscellaneous data (rule-based number formats and transliterators)
IxxDnnnn Base data


I60C0038 is the name of a converter for ICU Version 60 and code page ibm-1148_P100-1997.

However, in a MOVE ENCODED statement, Natural expects the long name of the code page that corresponds to the data item module. Any valid alias name of the code page can be used. The name of the code page is automatically mapped to the eight-character short name when the data item module is loaded.

For further information, see the appropriate ICU web site.

ICU Data Library Versus Data Item Modules

An ICU data library is faster but less flexible than dynamically loaded single data item modules. A data library is loaded once during session initialization.

The default ICU data library is usually sufficient for most applications but you may have to customize a data library to meet your particular requirements.

If you do not know which data item module you require, in a z/OS environment, you can load the extended, and therefore very large, data library ICSDTnnX. But this is a potential waste of space and can cause performance degradation, whereas single data item modules, which are dynamically loaded as required, occupy less space but still support the required code pages.

A single data item module is loaded when first accessed (for example, through a MOVE ENCODED statement). Single data item modules are especially useful for z/VSE and B2000, which do not support the extended data library ICSDTnnX.

Unicode and Code Page Support for Adabas

If a Natural session is enabled for code page or Unicode support, you should ascertain that Natural's Adabas user session also uses the appropriate user encoding for accessing Adabas data.

Because Adabas uses Entire Conversion Services (ECS) for conversion, the ECS name must be specified in the related NTCPAGE entry in module NATCONFG. To ascertain that Natural's Adabas user session uses the correct code page, specify the ACODE and/or WCODE option in the OPRB parameter for the databases used.

For more information on Adabas Unicode and code page support conversion, see the Adabas documentation for mainframes.

Translation Tables

Natural uses various tables for character translation and character property definition. The contents of the tables can be modified via profile parameters (TAB, UTAB1, UTAB2 and SCTAB) during the start of a Natural session.

If Natural is running with code page support (that is: the CP profile parameter is set to a value other than OFF), the tables cannot be modified by the user. In this case, the following Natural startup message will be issued to notify the user that the above mentioned session parameters are not considered:

Character translation parameter table-name ignored due to CFICU=ON.

Natural adjusts the tables automatically, according to the code page used for the Natural session (value of the system variable *CODEPAGE). See also Translation Tables in the Operations documentation.

Support of Multi-Byte Code Pages

Natural supports multi-byte code pages (MBCS) such as IBM-939 which is a Japanese code page based on EBCDIC and DBCS. Multi-byte code pages can be selected using the CP parameter (by setting CP to AUTO (if supported) or to the name of a code page). If Natural is running with a multi-byte code page, it uses internal I/O buffers which are based on Unicode. This means that all data written into the internal I/O buffers by an I/O statement are converted to Unicode. Due to the requirements of Unicode and multi-byte code pages, the size of the I/O buffers is increased as compared to the traditional I/O since Unicode characters need twice as much space as EBCDIC characters and enhanced attributes are needed to describe a field.

In the case of single-byte code pages (SBCS) such as IBM-1140, the traditional EBCDIC-based I/O is still used to preserve resources.