Re: PostgreSQL extension API? Documentation?

On Sat, Feb 27, 2016 at 10:37 AM, Álvaro Hernández Tortosa <aht@8kdata.com> wrote:
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>     Hi.
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>     I have a newbie question for extension development. Extensions provide an entry point, and are dynamically linked to PostgreSQL. But what APIs/functions are really available for extensions to call?
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>     The most obvious API is SPI. You could also implements hooks. Of course, functions, types, aggregates, whatever. But can an extension call other "internal" PostgreSQL functions? Is there any restriction to what could --or should-- call an extension? Is there any specific API, or any documentation which states what is available to use?
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>     In other words: what is the API surface exposed by PostgreSQL to extension developers? The assumption is that no PostgreSQL code should be modified, just adding your own and calling existing funcitons.
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