*NEW- The name for this activation group is selected by ILE and will always be unique. System-named activation groups are always deleted when the high level language returns.

*CALLER - Specifying *CALLER causes the ILE program or service program to be activated within the activation group of the calling program. A new activation group is never created with this attribute.

*NEW is the standard behavior that can be expected on other systems such as UNIX®.

Notes:

1.When you create a persistent CGI program, you must specify a named activation group.

2.CGI programs that are not persistent should not refer to job-level scoped resources.

For additional information about activation groups see, ILE Concepts, SC41-5606 book.

CGI Considerations

There are advantages to running CGI programs in either a user-named or *CALLER activation group. The performance overhead associated with activating a CGI every time that is requested can be drastically reduced. It is important to understand that because the system does not delete user-named activation groups, normal high level language end verbs cannot provide complete end processing. For example, the system will not close open files, and the system will not return the static and heap storage that are allocated by a program. The program must manage these resources explicitly. This will be especially important when moving CGI programs that rely on end processing to function properly.

Note: When you activate multi-threaded CGI on your web server, you get multiple thread support for your CGI application Your CGI application must end all of its threads before returning to the server. When using multi-thread capable CGI, you need to put the CGI program in a new or named activation group.

The following section shows examples which will work fine running in a *NEW activation group, however will cause problems if run in a user-named or *CALLER activation group.

Activation Group Problem Examples

Note

The following examples are not general CGI programming examples. For general CGI programming examples, see “Chapter 6. Sample programs (in Java, C, and RPG)” on page 89.

In the following example a CGI program when run in a *NEW activation group, would write Hello World to the browser. What is important to understand is that this application is taking advantage of job end processing to delete the stdio buffers that are used to buffer the stdout data.

You could build the following CGI program to run in either a user-named or *CALLER activation group. In such an instance, the server will not process the

18Web Programming Guide V4R5

Page 27 Page 29
Page 28
Image 28
IBM AS/400E manual CGI Considerations, Activation Group Problem Examples
Page 27 Page 29

AS/400E specifications

The IBM AS/400E, now more commonly known as IBM i, is a robust and versatile midrange server that has been designed to provide a comprehensive computing solution for businesses of all sizes. First introduced in the late 1980s, the AS/400 series has undergone multiple enhancements and rebranding, with the AS/400E being one of the notable iterations. This powerful platform is closely associated with IBM's commitment to reliability, scalability, and integrated business solutions.

One of the main features of the AS/400E is its highly integrated architecture that combines hardware and software into a cohesive system. This integration allows for seamless operations, reducing the complexity typically associated with managing disparate systems. The system is powered by IBM's proprietary OS/400 operating system, which has evolved into IBM i, featuring advanced capabilities like object-oriented programming, integrated database management, and security features that are essential for enterprise environments.

A key characteristic of the AS/400E is its robust database support, primarily through the use of DB2 for i. This integrated database management system enables efficient data handling and retrieval, facilitating real-time business analytics and reporting. Furthermore, the platform supports a variety of programming languages, including RPG, COBOL, and Java, making it flexible for developers who require diverse tools for application development.

The AS/400E is also known for its exceptional reliability and uptime, making it a preferred choice for critical business applications in industries such as finance, healthcare, and manufacturing. This reliability is backed by advanced error detection and correction mechanisms, as well as redundancy features that help prevent data loss and minimize downtime.

In terms of scalability, the AS/400E can effortlessly expand to accommodate growing business demands. Organizations can increase processing power by adding more resources without significant disruption. This scalability, combined with the system’s built-in virtualization capabilities, allows businesses to optimize resource usage and streamline operations.

Security is another defining feature of the AS/400E. The platform incorporates various layers of security measures, including user authentication, encryption, and comprehensive auditing capabilities, ensuring that sensitive business data is protected against unauthorized access.

Overall, the IBM AS/400E remains a powerful tool in the enterprise computing landscape, providing businesses with an integrated, reliable, and secure solution for their technological needs. Its enduring popularity is a testament to its capability to evolve with changing business requirements while maintaining its core attributes of high performance and stability.
Top Page Image Contents