Web services and dispatching engines
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I've done quite a bit of searching on this topic and I can never seem to find a common answers to this. What do most developers use to create dispatching systems for things like emails, purchase orders, etc? For example, if I place an order on a website, after the transaction goes through, what kind of a service dispatches the order to the 3rd party company? This has to be some type of process that runs on the server and retries until it succeeds. If it's a Windows server, do these websites use a windows service with polling? Seems a little primitive these days, considering that almost all websites need this type of thing for placing orders. Also, what is used on Linux?