WEBVTT

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So guys, we were going to write Netlink Hello world example.

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We shall write a Netlink Hello world userspace and Linux kernel module to demonstrate the netlink based

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communication.

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We shall design our userspace application which folks a separate thread to receive data from the kernel

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space while in the main thread.

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Our userspace application will send the data to the kernel space.

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Right.

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So our user space application would be like two threads.

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One is the main thread and another thread is the recipient thread.

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Right.

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While in the main thread, our userspace application will keep sending data to the kernel space, whereas

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in the another thread, our user space application will keep receiving the data from the kernel space.

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Right.

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So our user space application will be two threaded application.

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We will still use the same typical steps involved in socket programming.

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That is creating a socket specifying the source and destination address.

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Now we will see that in case of communication between user space and kernel space, what will be the

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source and destination addresses?

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Right.

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And what to specify in the bind system call?

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We will use the send message and receive message APIs to send and receive message as usual.

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And then we will finally close the connection using close so you can see that you must have used all

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these APIs while writing a typical socket program.

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As we discussed, that socket is a unified interface.

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Therefore, for any socket based communication will eventually going to involve the use of the same

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set of APIs.

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Netlink is no different and we will going to use the same set of APIs, right?

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So I will explain the new APIs that we shall encounter right in the code walk.

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So in the next section of the course we will begin a new project and incrementally add new code as we

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learn more and more new concepts.

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So let us start with building our first very basic netlink program.

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So in the next section we will going to write our first Netlink program.