With a search, the response might be the URLs of all the documents that met the search value. With a request that results in e-mail, the response might be a message that confirms that the system actually sent the e-mail.

Environment variables

Before you begin writing your CGI program, you need to understand the format in which the server will pass the data. The server receives the URL-encoded information and, depending on the type of request, passes the information to the CGI program. The server does this by using environment variables, command line arguments, or standard input.

A CGI application program should be able to handle a NULL value when getting an environment variable. For example, when the CGI program is trying to do a getenv(″CONTENT_LENGTH″) and the method is GET, the value would be returned NULL. This is because CONTENT_LENGTH is only defined in method POST (to describe the length of standard input).

The system supports the following environment variables:

AUTH_TYPE

If the server supports client authentication and the script is a protected script, this environment variable contains the method that is used to authenticate the client. For example:

Basic

CGI_ASCII_CCSID

Contains the ASCII CCSID the server used when converting CGI input data. If the server did not perform any conversion, (for example, in %%BINARY%% mode), the server sets this value to the DefaultNetCCSID configuration directive value.

CGI_MODE

Contains the CGI conversion mode the server is using for this request. Valid values are %%EBCDIC%%, %%MIXED%%, %%BINARY%%, or %%EBCDIC_JCD%%. The program can use this information to determine what conversion, if any, was performed by the server on CGI input data and what format that data is currently in.

CGI_EBCDIC_CCSID

Contains the EBCDIC CCSID under which the current server job is running (DefaultFsCCSID configuration directive). It also represents the current job CCSID that is used during server conversion (if any) of CGI input data.

CONTENT_LENGTH

When the method of POST is used to send information, this variable contains the number of characters. Servers typically do not send an end-of-file flag when they forward the information by using stdin. If needed, you can use the CONTENT_LENGTH value to determine the end of the input string. For example:

7034

CONTENT_TYPE

When information is sent with the method of POST, this variable contains the type of data included. You can create your own content type in the server configuration file and map it to a viewer. For example:

Application/x-www-form-urlencoded

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IBM AS/400E manual Environment variables
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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.
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