WEBVTT

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So, guys, now in this section of the course, we will going to learn how to write Netlink userspace

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program.

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So you can see on the slide that we will begin writing userspace Netlink program.

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This userspace program will do the following in userspace program.

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The very first thing that we will going to do is to create a userspace netlink socket.

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Then from the main thread we will going to create a separate thread which is called netlink message

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receiver thread.

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Right?

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So you can see in the below diagram that we have a userspace dot c program and from the main thread

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which is represented by the yellow line, we create a new thread which is represented by the blue line.

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Right?

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The purpose of this separate thread is only to receive messages coming from the kernel space, whereas

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in the main thread we will send the message to the kernel space.

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So our userspace application will be to threaded application.

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The main thread will take the responsibility to send the message to the kernel space, whereas the receiver

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thread will take the responsibility to receive the messages from the kernel space.

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So in the main thread we will ask the user for the input to send the greet message to the kernel.

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So in fact we can design the main thread as a menu driven program, giving users multiple choices to

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send different types of data to the kernel space as per the choice chosen by him.

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So in the main thread we will ask the user the input and accordingly we will send message to the kernel

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space receiver thread.

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On the other hand, only has the responsibility to receive a messages from the kernel space and in this

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case our receiver thread will going to receive a reply denoted by greet reply.

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Right.

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So the design of our user space application is fairly simple.

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It is two threaded application.

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The one thread will take the responsibility to send messages to the kernel space while the another thread

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does exactly the opposite.

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Right.