FCB Specification

POWER users specify the full eight-character FCB name, whereas OS/390 users only specify the last four characters. POWER supports device-independent specification of FCB-image phases in the * $$ LST statement by allowing ²$$$$² as the first four characters. POWER then replaces the dollar signs by a character string depending on the printer:

FCB1 For a 3800 printer

FCB2 For a PRT1 printer (3211, 3203-5, 3289-4, 3262) FCB3 For a 3203-1 printer

FCB4 For a 5203 printer FCB5 For a 4248 printer

$$$$ For any other printer type

In OS/390, users specify the four-character name of the FCB and JES2 uses the four-character prefix based on the device type. The FCB and UCS images are stored in SYS1.IMAGELIB with device-dependent prefixes.

See DFSMSdfp Advanced Services, SC26-4921 and DFSMS/MVS Utilities, SC26-4926 for OS/390 details.

10.3.4.9 UCS Naming Conventions

In OS/390, Universal Character Set (UCS) images are stored in SYS1.IMAGELIB with device-dependent prefixes. POWER does not have any particular naming convention that must be followed.

JES2 supports four-character UCS names on JCL statements submitted by the user. Depending on the printer device type, the following ¢UCSn¢ name is prefixed to the name which is then retrieved from IMAGELIB:

∙

∙

∙

∙

∙

∙

1403 - UCS1xxxx

3203 - UCS2

3211 - UCS3

4245 - UCS5

4248 - UCS6

3262 - UCS6

The IBM 3800, when driven by JES2, uses character arrangement tables beginning with XTB1.

For details, see DFSMS/MVS Utilities, SC26-4926, and DFSMSdfp Advanced

Services, SC26-4921

10.3.5 Interactive User Interfaces (ICCF/CMS/TSO)

Both VSE/POWER and OS/390 JES2 support interactive user interfaces for job submission and output retrieval, as well as other command functions. In addition, many VSE/POWER installations use VM/CMS as their interactive terminal system.

218VSE to OS/390 Migration Workbook

Page 241 Page 243
Page 242
Image 242
IBM OS/390 manual Interactive User Interfaces ICCF/CMS/TSO, UCS Naming Conventions, FCB Specification
Page 241 Page 243

OS/390 specifications

IBM OS/390, a versatile operating system, was a cornerstone in enterprise environments and played a pivotal role in mainframe computing. Released in the mid-1990s, OS/390 combined the strengths of IBM's MVS (Multiple Virtual Storage) with new features and enhancements, targeting scalability, reliability, and performance in demanding business applications.

One of the key features of OS/390 was its robust support for multiple users and processes. The system allowed thousands of concurrent users to access applications and data, ensuring high availability and minimizing downtime—a critical requirement for many large organizations. This scalability was supported through various enhancements in memory management and processor scheduling, enabling optimal resource allocation across diverse workloads.

OS/390 was known for its superior workload management capabilities. The Workload Manager (WLM) component allowed administrators to define service policies, specifying how system resources would be allocated according to the priority of tasks. This ensured that critical business processes received the necessary resources while less critical tasks were managed more flexibly.

Another significant characteristic of OS/390 was its commitment to security. The operating system provided comprehensive security features, including user authentication, data encryption, and auditing capabilities. This focus on security was vital for organizations handling sensitive data, ensuring compliance with regulations and safeguarding against unauthorized access.

OS/390 also supported advanced technologies that facilitated integration and development. The system included features like the IBM CICS (Customer Information Control System) for transaction processing and IMS (Information Management System) for database management. These technologies allowed organizations to build robust, high-performance applications tailored to specific business needs.

The ease of network integration was another strength of OS/390. With the advent of the Internet and global connectivity, OS/390 systems could easily interface with various network protocols, enabling businesses to operate in a connected world. This inclusion paved the way for many organizations to expand their capabilities and offer new services, driving digital transformation.

In conclusion, IBM OS/390 represented a significant advancement in mainframe technology, combining scalability, security, and robust workload management. Its rich feature set and support for critical enterprise applications solidified its role as a vital component of many organizations' IT infrastructures, ensuring they could meet their operational challenges head-on while supporting future growth. As technology continues to evolve, the legacy of OS/390 remains influential in the realm of computing.
Top Page Image Contents