FEOV Macro

VSE

FEOV

filename

 

 

 

 

(1)

 

 

 

 

 

 

 

MVS

FEOV

dcbaddress

,

REWIND

 

 

(1-12)

 

LEAVE

 

 

 

 

 

The basic functions of the VSE and MVS FEOV macros are the same. In MVS, volume positioning can be specified by the option operand; if no option is coded, the positioning specified in the OPEN macro is used. The MVS FEOV macro is valid for BSAM and QSAM.

GET / PUT Macros

VSE

GET

filename

,

workname

 

PUT

(1)

 

(0)

 

 

 

 

 

MVS

GET

dcbaddress

,

area address

 

PUT

(1-12)

 

(2-12)

 

 

 

 

(0)

 

 

 

 

 

The functions of the VSE and MVS GET/PUT macros are the same.

Figure 35 on page 302 shows a comparison of the MVS DCB and VSE DTFMT macros. Figure 36 on page 303 shows an example of using some of the preceding macros in a program.

Chapter 13. A s s e m b l e r 301

Page 325
Image 325
IBM OS/390 manual Feov Macro, GET / PUT Macros

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.