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An IBM Redpaper publication

Note: This is publication is now archived. For reference only.


Published on 29 December 2007

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IBM Form #: REDP-4324-00

Authors: Gary Mullen-Schultz, Susan Gantner, Jon Paris and Paul Tuohy

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    The number of APIs supplied with a system increases from release to release. After belonging to the realm of the “advanced” programmer, APIs are playing an ever-increasing part in our day-to-day applications, for example, you might want an application program to be able to retrieve invoices from a spooled file, convert those spooled files to PDFs, and e-mail them to the relevant customer. By supplying such functions in the form of APIs, i5/OS® makes the functions available to C, COBOL, Java™ , and RPG programmers.

    How many APIs are there? Well, back in 2003 there were over 1,500 APIs available to OS/400® developers. After that, we stopped counting!

    Given the increased use of APIs, we decided to:

    Describe how to find APIs

    Explain how to interpret the API documentation

    Explain how to use APIs

    Table of Contents


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