p,m,Y2x: Must be removed. DFSORT terminates if this operand is specified. p,m,Y2x can be specified in the OUTREC operand of DFSORTs OUTFIL

statement.

p,m,PZ: Must be removed. DFSORT terminates if this operand is specified.

p,m,PZ can be replaced by p,m,PD0,M11 in the OUTREC operand of DFSORTs OUTFIL statement.

p,m,PSI: Must be removed. DFSORT terminates if this operand is specified.

p,m,PSI can be replaced by p,m,PD,M11 in the OUTREC operand of DFSORTs OUTFIL statement.

p,m,ZSI: Must be removed. DFSORT terminates if this operand is specified.

p,m,ZSI can be replaced by p,m,ZD,M11 in the OUTREC operand of DFSORTs OUTFIL statement.

19.3.2 ICETOOL

DFSORT/VSEs ICETOOL and DFSORTs ICETOOL were designed to be functionally and syntactically compatible. However, differences between the VSE and OS/390 operating systems require the following changes when migrating:

JCL Statements: The VSE JCL statements describing the files used by ICETOOL must be changed to DD statements as described in the DFSORT Application Programming Guide, SC33-4035.

DEFINE operator: Must be removed. ICETOOL terminates if this operator is specified. ICETOOL obtains information about each input data set from the DD statement, data set control block (DSCB) or catalog.

FROM operand: Each FROM operand that specifies more than one filename must be changed to specify one ddname that identifies the input data sets using concatenation.

LIST operand: Each LIST operand must be changed to specify a ddname that identifies the list data set.

USE operand: Each USE operand must be replaced by a USING(xxxx) operand where xxxx is a unique four-character identifier. The control statements between (but not including) the USTART and UEND statements must be placed in a data set defined by an appropriate xxxxCNTL DD statement.

380VSE to OS/390 Migration Workbook

Page 404
Image 404
IBM OS/390 manual Icetool

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.