What Is Stub?

A stub is like a remote procedure call—but better. An RPC is how a client computer can remotely access procedures on a server computer. It's like calling a friend who lives across town and asking them to get you something from the store, except that the friend is in another state and your request is being channeled through the Internet. Two essential things need to happen with an RPC: first, the parameters used in a function call have to be converted because the client and server computers use different address spaces; second, these parameters need to be transmitted across an unreliable network connection. Stubs perform both of these tasks by taking care of all of the nitty-gritty details for you to focus on what matters: getting what you need from your friend! Stubs are like those awkward middle school dances where you have to dance with your ex-boyfriend even though you're in love with someone else. They're there to convert an RPC into a local function call so that the remote server computer can't tell the difference between a remote and a local function call. They are like the little black dresses of programming. They're simple, they're versatile, and they'll always get you out of a jam. Stubs are what are called "intermediate" libraries. You might also see them referred to as "dummy" or "mock" libraries, but those are just different ways of saying the same thing: a stub is a library that does nothing more than pass-through requests from one place to another without doing anything itself. Stubs have two primary uses in software development: client and server. Client stubs are generally installed on the client, while server stubs are installed on both client and server (although they don't necessarily need to be installed on both sides). Client stubs use parameters passed by clients to convert them into something that your application or vice versa can use. Server stubs transform parameters passed by clients into something that your application's functions can use, then reconvert results back into something that clients can understand after function execution has been completed—all without doing any actual work!