Descriptive Qualifier

Data Set Contents

 

 

LOADLIST

Output listing from loader

 

 

OBJ

Object module

 

 

OUTLIST

Output listing from OUTPUT command

 

 

PLI

PL/I statements

 

 

TESTLIST

Output listing from TEST command

 

 

TEXT

Uppercase and lowercase text

 

 

VSEBASIC

VSBASIC statements

 

 

Each field of a data set name consists of 1-8 alphameric characters and begins with an alphabetic or national ($, @, and #) character. The fields must be separated by periods. The total length of the name, including periods, must not exceed 44 characters.

The data set naming conventions simplify the use of data set names. If the data set name conforms to the conventions, you need specify only the user-supplied name field (in most cases) when you refer to the data set. The system will add the necessary qualifiers to the beginning and to the end of the name that you specify.

For example, entering the TSO/E EDIT command

EDIT PAYROLL(PRTCHK) NEW COBOL

puts your terminal into the Input mode of EDIT on a new member (PRTCHK) of a PDS with the name USERID.PAYROLL.COBOL where the USERID is the TSO/E user ID from UADS. This does not work when using ISPF, however, but even in this case you should use the descriptive qualifiers to provide a good indication of the contents of your data sets, which will make it easier for you to work with them.

In some cases, however, the system will prompt you for a descriptive qualifier. Until you learn to anticipate these exceptions to the naming conventions, you may wish to specify both the user-supplied name and the descriptive qualifier when referring to a data set.

Using TSO/E, data sets can be created and edited by subcommands of EDIT which reference line numbers or text within lines. The first method is called line-number editing and the second, context editing. These two methods can be used interchangeably. TSO/E does not offer a full screen edit capability. Again, though, with the installation of the Interactive System Productivity Facility (ISPF) program product a full screen editor is available to the TSO/E user and most users would not choose to use the TSO/E EDIT command. In fact, most TSO/E users will spend their entire session within ISPF using only its panels or graphical user interface.

For detailed information on the TSO/E EDIT command see TSO Extensions Command Reference. For information on ISPF see ISPF Getting Started.

160VSE to OS/390 Migration Workbook

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IBM OS/390 manual Edit Payrollprtchk NEW Cobol

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.