Table 36. REPORT and ISASIZE Options, C/370 and DOS PL/I

REPORT option, C/370

The information supplied by the REPORT option in C/370

and DOS PL/I

and DOS PL/I is supplied in LE/VSE by the RPTSTG option.

 

The RPTOPTS option may also be of use in determining

 

storage use.

 

 

ISASIZE option, DOS

In LE/VSE 1.4 the ISASIZE option maps to the STACK

PL/I

option. In OS/390 Language Environment ISASIZE maps

 

to STACK, NONIPTSTACK and PLITASKCOUNT.

 

 

17.4.2 C/370

C/370 is not an LE/VSE-conforming language. If your applications are written in C/370, you must convert them to another version of C before you can run them under OS/390. A well-coded C/370 application should generally recompile successfully with OS/390 C/C++, and run successfully with OS/390 Language Environment without modification.

Table 37 lists some migration considerations you should be aware of when migrating from C/370.

Table 37. C/370 Migration Considerations

Migration Consideration

Comments

 

 

Standard Streams

In C/370, you could override the destination of

 

error messages by redirecting stderr. OS/390

 

Language Environment determines the

 

destination of all messages from the MSGFILE

 

run-time option.

 

 

Passing Command Line

In C/370 if an error was detected with the

Parameters

parameters being passed to the main program,

 

the program terminated with a return code of 8

 

and a message indicating the reason the

 

program terminated. Under OS/390 Language

 

Environment the same message is displayed,

 

but the program also terminates with a 4093

 

abend, reason code 52 (hexadecimal 34).

 

 

Prefix of perror() and strerror()

With OS/390 Language Environment all

Messages in C

perror() and strerror() messages in C

 

contain a prefix. With C/370, there was no

 

prefix on these messages. The prefix is

 

EDCxxxxa where xxxx is a number (always

 

5xxx) and a is either I, W, or E.

 

 

Storage Report

The format of the run-time storage report

 

generated by the OS/390 Language

 

Environment RPTSTG run-time option is

 

different from the format of the storage reports

 

produced by the C/370 REPORT run-time

 

option.

 

 

17.4.3 VS COBOL II

VS COBOL II is not an LE/VSE-conforming language. However, VS COBOL II applications may run with OS/390 Language Environment with minimal changes. Subject to certain restrictions, you can transfer your VS COBOL II compiled object code from VSE to OS/390, link-edit with OS/390 Language Environment and run it there. This is discussed in Chapter 12, ªCOBOLº on page 249.

Chapter 17. Language Environment (LE) 355

Page 379
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IBM OS/390 manual 17.4.2 C/370, VS Cobol, Report and Isasize Options, C/370 and DOS PL/I, Migration Considerations

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.