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15738-SS1 IBM Operating System/400 V2
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3Document's Table of Contents:IBM U.S. Product Life Cycle DatesAbstractProduct PositioningHighlightsDescriptionTechnical DescriptionOperating EnvironmentHardware RequirementsSoftware RequirementsPlanning InformationPublicationsSecurity, Auditability, and Control
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5IBM U.S. Product Life Cycle Dates Program                                  Marketing   Service      ReplacedNumber   VRM     Announced   Available   Withdrawn   Discontinued    By
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75738-SS1 2.03.0  1993/12/16  1993/12/17  1995/12/29  1996/05/31   5716-SS15738-SS1 2.02.0  1992/02/18  1992/12/18  1994/09/06  1995/06/30       -5738-SS1 2.01.1  1991/04/22  1992/03/06  1992/12/18  1994/06/30       -5738-SS1 2.01.0  1991/04/22  1991/05/24  1992/03/06  1994/06/30       -
8
9Abstract
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11(For IBM US, No Longer Available as of December 29, 1995)
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13(For IBM US, Program Services Discontinued as of May 31, 1996)
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15The productivity of end users and programmers is enhanced when using the IBM AS/400* system because of the ease-of-use and design consistency of the Operating System/400 system. User interfaces are tailored to users of different skill levels.
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17Growth in the customer enterprise is enabled by the Operating System/400* support of the AS/400 hardware that ranges from the 9402 to the 9406. In addition, the single-level-store design of the Operating System/400 enables easy growth of the system's main storage.
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19Customer investment in skills and applications is protected by Operating System/400 support of standard software interfaces, conventions, and protocols called Systems Application Architecture (SAA)*. The migration capabilities of Operating System/400 protect customer investment in IBM System/36 or IBM System/38 applications, systems, and skills.
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21Electronic customer support, integrated functions for connectivity to remote devices and systems. Advanced peer-to-peer network facilities enhance the AS/400 systems management capabilities.
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23Operating System/400 enables business solutions with its extensive run-time application support, the 29 national language versions supported, and the externally-described data objects.
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25Product Positioning
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27Not available.
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29Highlights
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32Single Integrated Operating System for All Models 
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34Ease of Installation, Use, and Maintenance 
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36Extensive Run-time Application Function 
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38Productive Application Development Environment 
39
40Integrated Database 
41
42High System Availability 
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44Electronic Customer Support 
45
46Online Education 
47
48Comprehensive Security for System Resources 
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50Application Programming Interface to System Functions 
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52Printed Output Support 
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54Multiple Operating Environments 
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56Connectivity to Remote Devices, Systems and Networks 
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58Office Host Services 
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60National Language Versions and Multilingual Support 
61
62Publications Available
63
64Description
65
66What's New in Version 2 Release 3 of OS/400
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68
69The Integrated Language Environment (ILE) is an architectural enhancement to the AS/400 system to meet the challenge of providing new function and greater application design flexibility. ILE exploits modern high-level language (HLL) technology while protecting compatibility with existing applications. 
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71Network support enhancements include: SNA Primary LU2 support, APPC session level compression, and network maintenance enhancements. 
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73Availability enhancements include: the mixing of RAID 9337 Disk Array Subsystem and non-RAID DASD within a mirrored ASP, Save-While-Active across libraries, system limit improvements, and restore operational improvements. 
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755250 data stream support by DDS (Data Description Specifications) has been enhanced with certain Common User Access (CUA) Graphical User Interface (GUI) constructs that allows programmers to easily implement improved user interfaces for AS/400 applications. 
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77National Language Sort Sequencing enhances the development of collating sequence sensitive applications for single byte character set languages. Also, provided is workstation, printer and User Interface Manager (UIM) support enhancements. 
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79Enhanced security support (Security Level 50 - Designed to enable a C2 level of trust evaluation by the US Government). 
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81AS/400 Software License Management assists customers with managing the terms and conditions of software products that are available under the User-Based One-Time-Charge option.
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83Operating System/400 Version 2
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85The IBM Operating System/400 Version 2 licensed program provides system support for all models of the IBM AS/400 System. The single Operating System spanning all models of hardware represents a significant protection of customer investment in skills and applications. The following are some of the characteristics and functions:
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87Single Integrated Operating System for all Models
88
89All functions of the OS/400* follow a consistent design philosophy; this consistency is one of the cornerstones of AS/400 ease-of-use. The ease-of-use translates into higher productivity for its users and easier systems management. The Operating System/400 Version 2 licensed program includes everything described in this document. Some important characteristics are
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91
92Object-Oriented Architecture
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94All system and user resources are stored on the system as "objects," having a consistent architecture. Every object includes a description containing such information as the name of the creator and current owner, date created, object size (in bytes), date of last save, date of last reference, volume identifier of the media on which the save occurred, and text describing the object. 
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96Single-Level Storage
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98Object placement on different disk units is controlled by the system. The auxiliary storage disk units contribute to an overall pool of storage called single-level storage. It is not necessary to be concerned with where individual objects are placed; the libraries are used to locate any object. The architecture supports multiple disk allocations to store objects, and additional allocations are automatically added as an object (for example, a physical or logical file) grows in size. This capability requires that you monitor overall auxiliary storage capacity but not the sizes of individual objects. This contributes significantly to the ease of operating the AS/400 system. Auxiliary storage capacity can be added as needed without changing current application programs. 
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100Library Support
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102A library is a directory to objects (for example, programs and files), allowing a convenient grouping of the objects for either application or control purposes. Options exist to display, delete, or change objects in a library or to move or copy an object from one library to another. This function makes systems management of authorization to objects easier. The normal method of processing is to use a list of libraries to control how the system accesses objects. A library can also be secured to prevent unauthorized users from accessing any objects. 
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104Message Handling
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106Messages are displayed for various system and user operations. Message handling functions allow feedback for successful operations or to identify error conditions. Messages can be defined and sent between users, between users and applications, or between applications. Message replies can be sent; a "break" option allows immediate interruption of the end user's activities.
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108Each user and each work station device have a message queue. The user message queue can be sent messages by another user, a program, or the system; messages can also be sent to a particular workstation queue. 
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110Job Accounting
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112The system supports multiple levels of job accounting and captures job-related information through the assignment of account codes to users. The accounting information on defined units of work is recorded in a journal receiver and may be accessed and processed by user-written programs. 
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114Device Support
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116The operating system supports use of
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118Tape and diskette devices for data interchange and save/restore functions. A high level language (HLL) program or the copy command can read or write directly to a specific device.A range of work station printers for data processing or text quality output. Graphics (bar codes and images) may be printed with these devices.A range of work station displays, attached locally or remotely. Some devices support graphical data display.
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122Display Data Management
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124Interactive applications are supported by a screen definition language that provides greater flexibility in designing the "look and feel" of interactive interfaces. In addition, many attributes of the screen can be controlled outside application programs to simplify the development effort and improve programmer productivity (for tasks like validation of keyed input and punctuation of numeric output). Cursor-sensitive help information may be designed into user applications, including use of hypertext and index search function that allows easy access to descriptions of system functions. 
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126Data Description Specifications (DDS)
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128Data Description Specifications (DDS) enhancements support the new 5250 Display Data Stream extensions. There are four advantages to the 5250 display data stream extensions:
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131Application developers can define certain Common User Access (CUA) Graphical User Interface (GUI) constructs using DDS display files. The DDS GUI support includes: menu bars, pull downs, single choice selection fields, and multiple choice selection fields. Also, the support for DDS pop up windows now enables a GUI presentation.
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133From a single DDS application, the GUI constructs take on a different look and feel, depending on the device targeted.
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135
136An Enhanced User Interface (EUI) enabled PC 5250 emulator can present all-points-addressable GUI constructs. 
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138New InfoWindow II displays attached to an EUI enabled work station controller can present a GUI-like interface. 
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140Existing displays present an user interface style much like previously available on the AS/400 system.
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144Application developers can define improved entry field editing capabilities using DDS display files. The DDS support includes: continued entry field (not available for DBCS entry fields), programmable cursor progression, edit mask, and highlighted entry fields. 
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146Field level help is now available to DDS application developers. 
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148Performance of existing DDS windows applications will generally be improved when the device targeted is either an EUI enabled 5250 emulator, or a display attached to an EUI enabled work station controller.
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152Data Areas
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154The operating system supports a data area object that allows storage of up to 2,000 bytes of information, which can be accessed and updated by various programs within a single job or across jobs. Data areas are also directly supported by some HLLs. A local data area exists for any job and can also be used to pass information to programs submitted to batch or to other programs operating within a job. 
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156Data Queues
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158The operating system supports a call interface to send and receive information from a data queue object. This is designed to handle job-to-job communication with a high volume of requests. 
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160Work Management
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162The work management function eases the job of systems management by giving the operator control of the activities of a job and of its performance characteristics. Work management supports the concurrent execution of batch jobs, interactive jobs, and non-conversational transactions on the system. Each job is protected from other jobs on the system; however, job-to-job communication is allowed.
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164Different levels of interfaces to work management allow users to operate with the system defaults or tailor specific functions. Automatic tailoring of the execution environment to the CPU model, size of main storage, and configured devices can be done using an option. This automatically-established execution environment should provide good performance for many installations, although some may achieve better performance by changing some of the execution environment attributes. 
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166Save/Restore
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168Save is the capability of making a backup copy of objects or members on tape, diskette, or online save file. Restore is the capability to copy saved objects back to the original or a different system. The OS/400 save/restore functions are designed to ease the job of systems management.
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170Copying to a save file allows an unattended, off-shift save with a subsequent copy to media when the system operator is available. Saves can be done by library, object, changed object, or for all auxiliary storage, without regard to library or object contents. The system is available when saving documents and folders during normal operations; however, documents being updated during the save process are not saved. Saved objects--including single objects from a group of objects saved at one time, or members--including a single member from a multiple-member file--can be restored.
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172"Save while active" enables objects to be saved while they are being used by applications. The system ensures the entire object saved to the save media is consistent with the status of the object when the save operation was initiated. However, it is the user's responsibility to establish an application synchronization point either by temporarily quiescing the application for the time required to initiate the save operation or using journal/commit for all processes which impact any objects related to the save operation. 
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174Remote or Timed IPL
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176Key to convenient system management is the capability to power on the system manually or automatically, at a specific time of day, and from a remote location. Power down of the system can be done by a command executed interactively or under program control. 
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178Multiple Concurrent Tasks at the Same Work Station
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180Up to 16 different functions can be active as a result of a single sign-on to a work station. To switch from one function to another requires pressing an "interrupt" key and then selecting a new function from a menu. This can significantly increase the productivity of users who perform a variety of tasks of short duration (for example, interrupting an order entry application to switch to an unrelated inquiry application to answer a telephone request). It is also possible to sign on a second time and have two different sessions active, with up to 16 active functions in the second session). 
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182Performance Information
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184A user can manually collect system performance data for a single time period or automatically collect data on a weekly schedule using a set of commands/menus. This systems management function provides data to assist the user in workload scheduling, system tuning, performance reporting, performance-problem analysis, and capacity planning. The user can also work with this data using the Performance Tools/400 licensed program. 
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186Copy Facility
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188The copy facility copies data from one file to another. The files may be input from the database, tape, or diskette and be output to the database, tape, diskette or printer. Various options control format and record selection. 
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190Query Support
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192Applications may use OS/400 functions to display a list of queries for selection to execute or delete and to display a list of files available to query.
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194Some query capability is provided directly by OS/400. It includes processing database files, default output formatting, and windowing left and right for results that exceed the width of the screen. Extensive query capability is available with Query/400 (5738-QU1) licensed program and SAA Structured Query Language/400 (5738-ST1) licensed program. 
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196OS/400 Data File Utility (DFU) Support
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198Applications may use OS/400 functions to display a list of DFU programs to select for execution, and to display a list of files available to DFU. Some data entry capability is provided directly in OS/400. Functions include processing non-join database files, default selection of fields and record formats, and default audit log listing.
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200Ease of Installation, Use, and Maintenance
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203Operating system installation and modification are table-driven. Functions can be tailored by changing external tables of controlling variables. The installation of OS/400 software involves copying the system objects from the distribution media onto the system auxiliary storage. 
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205Automatic Configuration for Local Devices
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207The user can request that locally-attached devices be automatically configured. Local displays and printers can be added, changed or removed without affecting users signed on to displays connected to other controller ports. 
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209Operational Assistant
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211Operational Assistant (OA) presents a group of tasks, commonly done by an application end user or system operator, in easily understood non-technical terms. Users unfamiliar with the AS/400 system, its terminology, and sequence of steps to do a task are relieved of these complexities.
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213User productivity is improved by operational assistant making it easy to do tasks such as managing printer output, managing batch jobs, sending and answering messages. Systems management is facilitated by using OA to enroll and delete users on the system, to back up libraries, and automatically clean up job logs, history log files, and system journals. The system administrator is also assisted in setting up and scheduling simple backups, managing users signed on to the system, understanding the status of the system and managing the system's disk space.
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215The operational assistant function can be accessed in four ways:
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217
218Information Assistant
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220 
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222Information Assistant options were added in Version 2 Release 2 to provide one-stop shopping for a user's AS/400 Information needs. A menu provides selectable options to inform the user about where that look for information, how they can comment on information, and highlights about what is new in Version 2 Release 3 of the AS/400 system. In addition, access to searching the help index, starting online education and starting the question and answer function is provided. Information Assistant options are accessed from the AS/400 Main Menu, the Operational Assistant Information and Problem Handling menu, or by typing GO INFO on the command entry line.
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224Existing system commands, which have the parameter, ASSISTANCE LEVEL (basic, intermediate, or advanced)An attention program that brings up the OA main menuApplication programs that use the OA programming interfaces
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228Menu Interface
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230System-supplied menus to most system functions provide a task-oriented approach so that a user unfamiliar with control language can set up and use Operating System/400. The menus use an object-oriented approach by providing list of objects for the user to work with. A fast path gives quick access to system functions for the more experienced users. 
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232Online Help
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234The AS/400 help facility provides comprehensive explanations of display functions to help users be more productive. The index search facility can be used to request help for a task that involves multiple displays. Index search includes many synonyms so that users may ask for information in their own words or in the terms used by the system.
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236The help information provided is determined by the current location of the cursor on the display. It may be specific to a field or line on the screen, or to extended help on the use of the display as a whole. 
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238User Tool Library
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240The QUSRTOOL library contains tools that can provide business solutions or improve user productivity. These tools can be used as examples or enhancements to currently supported functions. They are provided with no plan of future enhancement or support. 
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242System Operation
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244System operational functions can be performed on an attended, partially attended, or a predominantly unattended basis. System operator functions can be interactively entered or executed under program control. Printer paper and media handling are manual functions. Various displays are provided to allow for control of jobs, spooling operations and communication lines. 
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246Problem Determination
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248Several system functions provide assistance in problem determination including dedicated and system service functions, messages, help information, and problem analysis commands.
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250A useful function in problem determination is copying a screen image from one work station for display on another work station. This is especially useful when used in conjunction with remote service support. 
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252Improved Software Problem Isolation and Data Collection
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254User-friendly, easy-to-use OS/400 tools provide customers with the ability to collect problem data at a central site. This OS/400 support for software problem isolation and data collection enables customers to recreate software problems, save the results, and then view the data from a central site. Initiation of the tools can be done locally or remotely. 
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256System Detected Software Problems
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258Symptom strings are now automatically created by the OS/400 licensed program at the time an error occurs, thus making management of problems in the system easier and recovery quicker. The automatic generation of symptom string data improves in the rate at which customers can find appropriate PTFs for problems. Problem resolution time is decreased when failure data is collected at the time of occurrence thus reducing the need for failure recreation. 
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260Programming Temporary Fixes (PTFs)
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262PTFs (including licensed internal code changes) may be loaded and applied using a command. Deferred PTFs can be applied only at IPL time, but an option allows this to be done unattended. PTFs can be shipped to a central site, either on media or electronically, and may then be packaged and distributed to remote or DSLO license sites, either on media or electronically. With the exception of the loading of media, the handling of PTFs can be automated for remote sites. 
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264Software Management Services
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266Software Management Services, a framework for software packaging, provides a consistent process for managing software on an AS/400 system. This consistent process covers IBM and non-IBM AS/400 software and PC-based software using AS/400 folders/documents support. When a vendor or customer uses the SystemView System Manager/400 licensed program to package an application, that application can now be installed and maintained using the same procedures that are used for installing and maintaining IBM AS/400 licensed programs. These procedures include software media packaging and distribution, application installation, application registration within the AS/400 system, and application servicing. Convergence to a common process for packaging enables the OS/400 facilities to provide consistent management of these packaged applications. This reduces redundancy and inconsistencies for applications and current procedures.
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269System Password
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271For Version 2 Release 2 or later, support was added to detect processor model changes on the 9404 and 9406 AS/400 systems through the use of a 16 digit system password. In Version 2 Release 3, the system password was added to the 9402 system. The purpose of the System Password is to identify all model changes to:
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274Help maintain the quality and integrity of the AS/400. 
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276Ensure that IBM is paid the applicable charges due for the use of its licensed programs, including those having processor-based charges. 
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278Ensure the protection of IBM's intellectual property including IBM Licensed Internal Code.
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280After Version 2 Release 2 or later is installed, the system requires a single entry of the system password at the time of a system model change. If the correct system password is not entered, a temporary system password bypass can be selected to allow time (70 days) to obtain the correct system password. The customer can obtain the correct system password by contacting his marketing representative and having him place an RPQ order for the system password. If the correct system password is not available and the system password bypass time ends, the system will not complete the next IPL until the correct system password is obtained and entered. While in bypass mode, the system indicates through informational console messages the time remaining until the bypass time ends.
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282In Version 2 Release 3, the system password support is extended to include the 9402 system and to detect system movement that may indicate possible system ownership change. The support is intended to prevent software licenses from moving with used or auctioned equipment. If a condition is detected that indicates possible ownership change, the stored system password will be invalidated and a new system password version must be obtained and entered. If the system password is invalidated, the system password bypass can be selected to continue system usage for the duration of the bypass time. If the required new system password version is not obtained and entered into the system before the bypass time ends, the system will not complete the next IPL.
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284Extensive Run-time Application Function
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286Operating System/400 is a functionally-rich platform for applications. Because it is enabled to run a wide range of applications, customers can easily grow their application base as their business needs grow. The extensive run-time function integrated into the OS/400 system enables applications that use the following support to run without the corresponding products:
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288ILE C/400COBOL/400AS/400 BASICAS/400 PascalAS/400 PL/1FORTRAN/400RM/COBOL-85RPG/400REXXStructure Query Language/400 (SQL)Query/400SAA Query CPISAA Print CPISAA CPI-CommunicationsData File Utility (DFU) (a part of the Application Development Tools licensed program, 5738-PW1)SortC library functionsOffice host servicesBanking and financeBinary synchronous communications (S/36, S/38, ICF, and batch)System/36 execution environmentSystem/38 execution environmentDistributed Data Management (DDM)Intersystem communications function (ICF)
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290Cross System Product/Application Execution (CSP/AE)
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292The CSP/AE function in Operating System/400 executes applications generated on a System/370, using Cross System Product Version 3 Release 2 Modification Level 1, Version 3 Release 2 Modification Level 2 or Version 3 Release 3. This function protects investment by enabling applications to be portable across systems and supports migration to new hardware platforms. Some applications can be regenerated for a new target environment with no changes to the original source specifications. OS/400 CSP/AE functions are compatible with other CSP/AE environments.
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294The CSP/AE function of OS/400 includes:
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297CSP object management, which provides the system administrator with tools necessary to install and manage CSP/AE applications in the OS/400 operating environment. It executes in batch and interactive environments. 
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299CSP application execution facility controls user interactions with an execution of CSP/AE applications generated by CSP/AD on a System/370 for execution on the AS/400 system.
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301Highlights of the CSP/AE component of the OS/400 operating system:
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304Cross System Product applications are stored as executable program objects (similar to load modules), which are compatible with applications of other OS/400 programming languages. There is no Cross System Product Application Load File (ALF) in OS/400. Standard OS/400 system commands also work with all Cross System Product application program objects. 
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306OS/400 Data Description Specifications (DDS) source members can (optionally) be created for an application's database files during application install processing. The system administrator may then create the physical and/or logical database files from this source, for use by the application. Required DDS information can be generated, with the application, by CSP/AD on the System/370. 
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308A user message file created on a System/370 using the Cross System Product Message File Utility can be transported to the AS/400 and loaded as an OS/400 message file. Standard OS/400 system commands can then be used for message file maintenance. 
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310Standard OS/400 system commands are supplemented by a set of CSP/AE object management functions. These functions have either menu or command interfaces that operate on Cross System Product programs and all related table and map group objects. 
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312Cross System Product application trace capabilities to aid in problem isolation involving Cross System Product applications. Trace functions include program calls, Input/Output, object references, process names, application statements, SQL data areas, and Move/Compare/Math source operands. Options can be dynamically modified during interactive application execution.
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314Productive Application Development Environment
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316Operating System/400 includes many functions to assist in programming the system. These functions, along with the Application Development Tools (5738-PW1) licensed program, provide a productive application development environment. This environment supports a hierarchical approach to application development which can increase programmer productivity. The programming functions included in OS/400 are:
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318
319Interactive Debug
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321These facilities increase programmer productivity by providing assistance in creation and maintenance of programs written in RPG/400, COBOL/400, BASIC, PL/I, CL, and Pascal. Debugging of batch or interactive jobs can be done at any time; no special compilation is needed. 
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323Command Prompting
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325Productivity of users executing commands is increased by command prompting. Each system and user command can be prompted for help with parameters. Parameters can be filtered based on values previously entered or predetermined parameters. Online help explains parameters and values. 
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327Cross-Reference Facility
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329Programmer productivity is increased by relieving the burden of cross-referencing. The system has the capability to cross-reference files to related programs and fields to related files. 
330
331Programmer Menu
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333Using this menu, creation and maintenance of objects require minimal use of system commands. 
334
335Interactive Data Definition Utility (IDDU)
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337IDDU assists in the creation of database files by creating IDDU data dictionaries, defining files, record formats, and fields. Programmer productivity is thus enhanced by using IDDU. It is an alternative to using Data Description Specifications (DDS). Easy-to-use functions within IDDU assist in the creation of files with existing field definitions. 
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339Interfaces to System Functions
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341Call-level interfaces enable programmers to create extensions to OS/400 functions and system applications. These interfaces provide fast access to the information in selected system objects, such as
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343Object descriptionsJob informationSpooled filesDatabase informationDocument library objects
344
345 
346
347Integrated Language Environment (ILE)
348
349The Integrated Language Environment (ILE) is an architecture enhancement to the AS/400 system to meet the challenge of providing new function and greater application design flexibility. ILE exploits modern high-level language (HLL) technology while maintaining compatibility with existing applications.
350
351The AS/400 system's ability to integrate multiple applications from multiple independent sources is improved. Each application is allowed to define its own boundaries. Multiple applications within the same job each have their own commitment control in effect for data base management. This is accomplished through improved isolation in data and commit scoping.
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353ILE provides a common framework for ILE conforming languages in the areas of program activation, storage management, condition management, and program debugging. ILE also defines calling conventions for access to ILE bindable APIs and provides consistency and improved performance for interlanguage communication.
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355Also, provided is the Dynamic Screen Manager (DSM). The DSM offers versatility and adaptability in generating screens during application execution. DSM provides a set of bindable APIs for low level, window and session services.
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357New elements introduced by ILE:
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359ILE Program BinderILE Message HandlingILE Source DebuggerILE Dynamic Screen Manager
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361ILE Program Binder
362
363With the introduction of the Integrated Language Environment come the introduction of a new step in the application development process, binding. The purpose of binding and the Binder is to create program objects in such a way that efficient external calls may be performed.
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365The Binder will support all the new ILE compilers being built in Toronto or Santa Theresa.
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367These compilers will create modules (object type *MODULE) and the Binder will bind several modules together to form a program object. Note that these ILE program objects are logically as well as physically different from unbound program objects.
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369The Binder will provide several commands for creating and managing program objects.
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371ILE Message Handling
372
373Message Handling support of Job Message Queues has been modified extensively. Support for Standard Message Queues has remained essentially unchanged. The changes being made in the area of Job Message Queues are in support of the Integrated Language Environment architecture. The new Job Message Queue support applies to both prior program model and ILE programs. There is only one version of Message Handling and only one version of the Job Message Queue support.
374
375Message Handling supports the new ILE Exception Model. The new ILE Exception Model introduces new constructs for exception and messaging support at the micro code level.
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377
378New Exception Related Constructs
379
380ILE introduces a new exception model. In particular, the concept of a message and the concept of an exception are unified in ILE. A message and an exception will be sent at the same time. The concepts of monitoring for an exception and handling an exception remain unchanged for a previous program model program but are significantly changed for a ILE program.
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382The new exception model is applicable to both previous program model and ILE programs. The existing Message Handling commands have been enhanced to support the ILE Exception Architecture. In most cases, the enhancements are fully upward compatible. However, there are a few instances where incompatibilities will be introduced to the external users of the Message Handling interfaces. 
383
384Support for Expanded Message Content
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386Additional Message Information (AMI) panels and the Job Log print format have been modified to support expanded message content. In particular, Message Handling supports the fully qualified ILE procedure name which consists of bound-program-name, module-name, and procedure-name. This fully qualified name can appear as either the sending program or receiving program name. Unbound programs will continue to be identified by program-name only. 
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388Changes to User Interface
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390Message Handling has changed the DDS for the printed JOBLOG taken from the Process Queue Space object. A message can contain more information than is possible today. The printed job log and the Additional Message Information screen have been changed.
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392The openness APIs that support Message Handling functions have been enhanced to support the new exception model constructs.
393
394The SNDPGMMSG, RCVMSG, and RVMMSG commands have been changed.
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396ILE Source Debugger
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398The Non Programmable Terminal Integrate Language Environment Source Debugger will be shipped as part of OS/400 and available to all AS/400 customers. It is used to debug all bound programs and service programs. This debugger is a source debugger, allowing debugging to be done in terms of the source associated with a program. It will not debug the previously unbound programs. These programs must be debugged with the system debugger and EPM debugger, respectively.
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400A debugger API will be provided, allowing compilers and other pre-processors which contribute to module creation to create debug view information associated with a module object. The API allows source debuggers to be built for the AS/400 system.
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402The debugger provides debug function in several areas, including module source, program flow of control, and program data.
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404
405Module Source
406
407When a program is debugged, the source for the modules is displayed. The basic debug screen shows mostly source, allowing debug commands to operate against this source. When a runtime error occurs in a program, such as a divide by zero, the debugger will display the source of the program, and indicate where the error occurred in terms of a position in the source of the module.
408
409When looking at the source displayed by the debugger, it is possible to change the view being displayed. This allows the user to determine what was generated by a particular line of source. For example, with the cursor on a macro invocation in the Source View, the user can select the Listing View, which will show the expansion of the macro invocation. 
410
411Program Flow of Control
412
413These functions allow the user to observe the flow of control of a program being debugged. The functions provided are: BREAKPOINT (a program can be stopped at a specified location), CONDITIONAL BREAKPOINT (a program can be stopped at a specified location when a specified condition is met), and STEP (the execution of a program is stopped at every statement, allowing the flow to be observed).
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415The operation of these functions depends on which view is being displayed. For example, if the Source View is displayed, a breakpoint can be set on any source line. However, if the Listing View is being shown, a breakpoint can be set on every statement, including statements in a macro invocation. One macro invocation in the Source View may produce many statements in the Listing View. 
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417Program data
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419These functions provide for the displaying and changing of program variables. These variables will be displayed according to their type, such as integer, enumerated, etc.
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421The user may enter a C expression, which will be interpreted and the results displayed.
422
423These functions depend on the position in the view being displayed, since variables may be inside procedures and not visible to all parts of the program. For example, when displaying the variable x, it will depend where the view is currently positioned when determining which x to display.
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425Dynamic Screen Manager (DSM)
426
427Dynamic Screen Manager offers versatility and adaptability in generating screens during application execution with a set of bindable Application Program Interface (APIs). DSM enables ILE developers to create screens and windows dynamically, no longer requiring predefined static screens. This provides improved programmer productivity over using UDDS to perform low-level screen I/O operations and greater flexibility in controlling the screen appearance dynamically for the application. The DSM support falls into the following categories:
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429
430Low level services - provides a simple API interface to the UDDS commands, greatly simplifying applications that require low-level control of the screen. 
431
432Window services - supports the dynamic creation, drawing, selection, moving, and re-sizing of one or more windows on the screen. Data and fields can be defined inside the windows. 
433
434Session services - provides support for dynamically placing data inside an area of a window and scrolling the data, similar in concept to subfiles.
435
436National Language Sort Sequencing
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438NLSS will make it easier to develop collating sequence sensitive applications. In addition to providing sort sequence tables which represent both unique and shared weight default sort sequences for over forty Single Byte Character Set (SBCS) languages and making it easier for sort sequence tables to be created, many commands and system support functions have been enhanced to allow a single sort sequence table to be referenced in all parts of the application. Reference to the system provided tables can be made symbolically.
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440Workstation, Printer, and User Interface Manager (UIM) support
441
442Workstation, printer and UIM support is enhanced by removing the requirement that the user matches the CHRID (Character Set and Code Page) of his workstation display with the CCSID (Coded Character SET ID) of their job. This removes the requirement that the CHRID of the printer file be equal to the CHRID of the user's job CCSID. In addition, conversions between the encoded graphic characters is now supported between all of the languages supported by the AS/400 system.
443
444Integrated Database
445
446The integrated AS/400 database offers many advantages. The same copy of data may be shared by applications using file and database interfaces, by applications using SQL, by system utilities, and by basic system functions. This data sharing, along with the data mapping features of views and logical files, reduces the need for redundant copies of data. The database is installed with OS/400. This eliminates a separate installation procedure and automatically starts the database and recovery functions when the system is IPLed. Integration also allows the database commands and display interfaces to have a look and feel that is consistent with the rest of the system. For example, database objects are automatically included as part of the system-wide cross reference facilities and the basic system administration commands for save, restore, security, and object management can be used to administer the database. This allows the database to exploit new system functions and hardware for improved availability, recovery, security, concurrency, and performance.
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448
449Relational Model
450
451The database support is integrated into the machine and the operating system. It provides a high degree of data integrity and programmer productivity. A relational database by design, it may be viewed by users in terms of a relational model or a file model, depending on their choice of interfaces. Those choosing the relational model see tables and views while those using the file model see physical and logical files. The data resides in